In the fascinating world of microbes, entomopathogenic fungi are a special group of fungi with a unique and mysterious role in nature. They infect and kill insects. This ability makes them valuable agricultural allies, where they are used as natural pest control agents. In this article, what are the entomopathogenic fungi, how do they work, and their importance in sustainable agriculture are explored.

Who are the Entomopathogenic Fungi?

Entomopathogenic fungi are a group of fungi that infect and kill insects. The term “entomopathogenic” comes from the Greek words “entomo,” meaning insect, and “pathogenic,” meaning causing disease. These fungi can be found in various environments, including soil, water, and on plant surfaces. They play a crucial role in controlling insect populations in natural ecosystems.

How do Entomopathogenic Fungi Work?

The life cycle of entomopathogenic fungi is complex and consists of step by step process. The fungal spores, known as conidia, come into contact with the insect’s exoskeleton. Using specialized structures called appressoria and enzymes like cutinase, the spores attach firmly to the insect’s cuticle. Once attached, the spores are germinated, forming germ tubes that penetrate the exoskeleton of insects.
After penetration, the fungi secrete cutinase that degrades the insect’s cuticle, allowing the fungal hyphae to invade the insect’s body. Inside the insect’s body, Fungi proliferate inside of the insect’s body, spreading throughout the body and consuming the insect’s internal tissues.
The fungi continue to grow and multiply within the insect, eventually leading to the insect’s death. The time from infection to death can vary depending on environmental conditions and the fungus species involved.
After the death of the insect, fungi emerge from the cadaver and produce new spores on the insect’s surface. These spores are then released into the environment, where they can infect other insects, continuing the cycle.

● Natural Pest Control

One of the most significant benefits of entomopathogenic fungi is their use in natural pest control. Unlike chemical pesticides, these fungi specifically target insects without harming other organisms or the environment which makes them an eco-friendly alternative for managing insect pests in agricultural systems.

● Targeting Resistant Pests

Many insect pests have developed resistance to conventional chemical pesticides, making them harder to control. Entomopathogenic fungi offer a solution by providing a different mode of action in which they infect insects through physical and biological means, thereby, pests are less likely to develop resistance to these fungi.

Chemical pesticides can have detrimental effects on the environment, including soil and water contamination, and harm to non-target organisms like bees and other beneficial insects. Entomopathogenic fungi, being a natural part of the ecosystem, pose minimal risk to the environment. They can be used as part of an integrated pest management (IPM) strategy, reducing the reliance on chemical pesticides and promoting sustainable farming practices
Several species of entomopathogenic fungi are used in agricultural pest control. Some of the notable examples are:
Beauveria bassiana
Beauveria bassiana is one of the most widely studied and used entomopathogenic fungi. It infects a wide range of insect pests, including aphids, whiteflies, and beetles. B. bassiana spores attach to the insect’s cuticle, penetrate it, and proliferate within the insect, eventually killing it. This fungus is used in various biopesticide formulations for controlling pest populations in crops.

Metarhizium anisopliae
Metarhizium anisopliae is another important entomopathogenic fungus with a broad host range, including termites, grasshoppers, and mosquitoes. It works similarly to B. bassiana by infecting and killing insects from the inside to the out. M. anisopliae is used in both agricultural and public health applications, such as controlling mosquito populations to reduce the spread of diseases like malaria and dengue fever.
Lecanicillium lecanii
Lecanicillium lecanii is effective against soft-bodied insects like aphids, whiteflies, and thrips. It is commonly used in greenhouse and indoor plant cultivation, where controlling insect pests is critical for maintaining healthy plants. L. lecanii infects its host by penetrating the insect’s cuticle and growing inside, leading to the insect’s death.

While entomopathogenic fungi are invaluable in the battle against agricultural pests, their practical application faces several challenges. Understanding and addressing these challenges is essential for maximizing the effectiveness of these natural pest control agents.

● Environmental Sensitivity

Entomopathogenic fungi are highly sensitive to environmental conditions. Factors such as temperature, humidity, and UV exposure significantly impact their viability and effectiveness. For instance, high temperatures and low humidity can inhibit spore germination and fungal growth, reducing their ability to infect and kill insects. Similarly, exposure to UV radiation from sunlight can degrade fungal spores, rendering them ineffective. Developing formulations that enhance the fungi’s stability under diverse environmental conditions is crucial for their successful application.

● Application Methods

Effective delivery of entomopathogenic fungi to target pest populations is another significant challenge. Traditional application methods, such as spraying fungal spores, may not always ensure even distribution or sufficient contact with the pests. Additionally, fungal spores can be washed away by rain or irrigation, reducing their efficacy. Innovative application techniques, such as encapsulating spores in protective coatings or using drones for precise delivery, are being explored to improve the fungi’s performance in the field.

● Pest Resistance and Specificity

While entomopathogenic fungi offer a different mode of action compared to chemical pesticides, there is still a risk of pests developing resistance over time. This can occur, if fungi are used repeatedly without rotation or in combination with other pest control methods. Furthermore, the specificity of certain fungi to particular insect species can be a limitation, as a single fungal species may not effectively control all pest types present in a crop. Integrating fungi into an integrated pest management strategy, which combines multiple control methods, can help mitigate these issues.

● Cost and Production

Producing entomopathogenic fungi on a large scale can be costly and technically challenging. The cultivation, harvesting, and formulation processes need to be optimized to ensure that the fungi remain viable and effective. Additionally, the costs associated with developing and registering biopesticide products can be high, potentially limiting their availability and adoption by farmers.

The use of entomopathogenic fungi in agriculture is a promising field with the potential to revolutionize pest control practices. Research is ongoing to discover new fungal species with entomopathogenic properties and to improve the efficacy of existing ones
Entomopathogenic fungi represent a natural and sustainable solution for managing insect pests in agriculture. By harnessing the power of these fungi, farmers can reduce their reliance on chemical pesticides, promote environmental health, and ensure the long-term sustainability of their farming practices. As research and technology continue to advance, the role of entomopathogenic fungi in agriculture is likely to grow, offering new opportunities for eco-friendly pest management.

By Udara Nawarathne

References
●    Khan, S., Guo, L., Maimaiti, Y., Mijit, M., & Qiu, D. (2012). Entomopathogenic Fungi as Microbial    Biocontrol    Agent.    Molecular    Plant    Breeding. https://doi.org/10.5376/mpb.2012.03.0007

●    Litwin, A., Nowak, M., & Różalska, S. (2020). Entomopathogenic fungi: unconventional applications. In Reviews in Environmental Science and Biotechnology (Vol. 19, Issue 1, pp. 23– 42). Springer. https://doi.org/10.1007/s11157-020-09525-1

●    Shah, P. A., & Pell, J. K. (2003). Entomopathogenic fungi as biological control agents. In Applied Microbiology and Biotechnology (Vol. 61, Issues 5–6, pp. 413–423). Springer Verlag. https://doi.org/10.1007/s00253-003-1240-8

Bio fertilizers and bio pesticides can be introduced as eco-friendly alternatives for chemicals derived from beneficial microbes like bacteria and fungi.

Biofertilizers: These are very important in helping plants to access nutrients more efficiently. For example, nitrogen-fixing bacteria, capture atmospheric nitrogen and make it usable for plants, reducing reliance on chemical fertilizers and microbes such as phosphate-solubilizing microorganisms, solubilize insoluble phosphorus within the soil, making it readily available for plant absorption. The significant benefits of using biofertilizers are:
• Enhance Nutrient Uptake: Certain microbes act as tiny factories, fixing nitrogen from the air or solubilizing phosphorus locked in the soil, making these vital nutrients readily available for plants. This reduces reliance on synthetic fertilizers while promoting soil health in the long run.

• Boost Plant Growth: Beneficial microbes can encourage plant growth by promoting root development, enhancing nutrient uptake efficiency, and even producing growth hormones.

• Reduce Reliance on Chemicals: The overuse of chemical fertilizers can lead to soil degradation and pest resistance. Biofertilizers offer a way to break this cycle, promoting a more sustainable agricultural system.

• Improve texture, structure, and water-holding capacity of soil: Biofertilizers enhance soil fertility and structure by promoting beneficial microbial activity. Microbial metabolites produced by microbes can bind soil particles together to form aggregates.

Biopesticides: These are the microbial weapons that combat pests and diseases in a natural way other than using chemicals. For example, some bacteria produce toxins that are lethal to specific insects, while others disrupt the growth and development of harmful fungi. Bio-pesticides are often more targeted than chemical pesticides to minimize harm to beneficial insects and the environment. The importance and benefits of using biopesticides are as follows.

• Targeted Pest Control: Unlike broad-spectrum chemical pesticides, bio-pesticides often target specific pests, minimizing harm to beneficial insects like pollinators crucial for our ecosystem. This promotes a more balanced and healthier agricultural environment.

• Reduced Environmental Impact: Biopesticides typically degrade quickly in the environment, posing less risk of soil and water contamination compared to chemical alternatives. This minimizes the harm to beneficial insects and wildlife.

• Lower Risk of Pest Resistance: The diverse nature of biopesticides makes it harder for pests to develop resistance compared to single-molecule chemical pesticides.

• Safer for Humans and Animals: Biopesticides generally have lower toxicity levels for humans and animals compared to many chemical pesticides. This reduces the risk of health problems associated with exposure to synthetic chemicals.

Even though there are several benefits given by the use of these natural and eco-friendly inhibitors, some identified limitations minimize the possibility for them to act as silver bullets in the field of agriculture.
One of the commonly identified limitations is efficacy concerns and consistency.
Biofertilizers and biopesticides can sometimes be less predictable in their effectiveness compared to their chemical counterparts. Environmental factors like temperature and humidity can influence their performance. The effectiveness of biofertilizers can vary depending on factors such as soil type, climate, and crop species. Having a proper understanding and optimizing microbial interactions and formulations helps to ensure consistent performance.
Storage and shelf life are other limitations noted in the use of fertilizers and biopesticides. Some bio fertilizers and bio pesticides require specific storage conditions and have shorter shelf life compared to chemicals. In addition to storage, it is a huge challenge to prepare them for large scale. Cost considerations and accessibility are other limitations we come across with the use of eco-friendly materials compared to synthetic chemicals. Bio fertilizers and bio pesticides are cost-effective in the long run. However, their initial production cost is high due to the identified challenges. Accessibility for them is also higher than chemical options because resources are limited for farmers. Scaling up production and adoption of bio-based solutions to meet global agricultural demands which are foremost required investments in research, infrastructure, and education. Accordingly, it is also a challenge that we come across in the use of biocontrollers. Proper application methods and timing are crucial for maximizing the benefits of bio-fertilizers. Transitioning from chemical-intensive to bio-based agriculture requires careful integration with existing farming practices. For that, proper training including training and support for farmers to optimize application methods and timing. Policy and Regulatory Considerations are other foremost aspects of bio-based agriculture.

Biofertilizers, biopesticides and the future of agriculture:

While bio fertilizers and bio pesticides offer substantial benefits for sustainable agriculture, their full replacement of chemical inputs results in challenges. Therefore, it is important to have strategic approaches to overcome them. Some of them are as below.

• Research and Innovation: Continued research is crucial to enhance the efficacy, stability, and application methods of bio-based products. Innovations in microbial technologies and formulation techniques can improve their performance and scalability

• Education and Outreach: Increasing awareness among farmers about the benefits and proper use of bio-based alternatives is essential for fostering adoption and overcoming skepticism.

• Policy Support: Governments and agricultural agencies play a pivotal role in incentivizing the transition to bio-based agriculture through supportive policies, subsidies for research and development, and regulatory frameworks that promote sustainable practices.

• Collaboration and Partnerships: Stakeholders across the agricultural value chain—farmers, researchers, industry, and consumers—must collaborate to address challenges and leverage opportunities for scaling up bio-based solutions.
Biofertilizers and biopesticides are unlikely to fully replace chemicals in the near future. However, they can be a crucial part of a sustainable agricultural strategy called Integrated Pest Management (IPM). IPM combines methods like:

• Cultural practices: Crop rotation, tillage practices, etc.
• Biocontrol agents: Including beneficial microbes like those in biofertilizers and biopesticides.
• Judicious use of chemicals: Only when necessary and with targeted options.

While bio fertilizers and bio pesticides hold promise as sustainable alternatives to chemical inputs in agriculture, they likely won’t completely replace chemicals in the immediate future due to practical and logistical hurdles. A combination of approaches that leverage the power of microbes alongside responsible chemical use seems to be the most realistic path forward for a healthy and sustainable agricultural future.
To summarize, while biofertilizers and bio-pesticides offer significant environmental and agronomic benefits, their full integration into mainstream agriculture requires overcoming technical, economic, and regulatory barriers through collaborative efforts across the agricultural sector.

G.S Kanchana

References:

• Moharana, P.C. and Biswas, D.R., 2020. Biofertilizers and biopesticides: A holistic approach for sustainable agriculture. Journal of Environmental Management, [online] Available at: https://www.sciencedirect.com/science/article/abs/pii/S030147972030733X [Accessed 19 July 2024].

• Biondi, A., Desneux, N., Siscaro, G. and Zappalà, L., 2012. Comparative effectiveness of biopesticides in pest management and crop productivity. Agriculture, Ecosystems & Environment, [online] 144(1), pp.28-
• 36. Available at: https://www.sciencedirect.com/science/article/abs/pii/S0167880917302160 [Accessed 19 July 2024].

• Lucy, M., Reed, E. and Glick, B.R., 2016. Biofertilizers: A Pathway to Sustainable Agriculture. Frontiers in Plant Science, [online] 7, p.419. Available at: https://www.frontiersin.org/articles/10.3389/fpls.2016.00419/full [Accessed 19 July 2024]

Images:
• https://microbeonline.com/biopesticides/
• https://link.springer.com/chapter/10.1007/978-3-030-48771-3_6

Bioluminescence refers to the process by which living creatures emit light and produce light themselves. In addition to some species of bacteria, fungi, jellyfish, insects (such as fireflies), and deep-sea critters, this phenomenon can also be observed in other organisms. A light-emitting molecule known as luciferin and an enzyme known as luciferase are both involved in the chemical reaction that results in the production of light. The vast majority of light-producing bacteria, also known as bioluminescent bacteria, can be discovered in the digestive tracts of marine creatures, the surface of dead fish, sandy bottoms, and seawater. The phenomenon of bacterial bioluminescence can also be observed in freshwater and terrestrial bacteria, albeit with a somewhat lower frequency. These bacteria are capable of living independently or in conjunction with other living organisms. As a result of the organisms that serve as their hosts, these bacteria are provided with a safe environment in which to reside and adequate sustenance. On the other hand, the hosts make use of the light that the bacteria emit to maintain their sexual attractiveness, attract prey, and/or conceal themselves. In their interactions with other organisms, bioluminescent bacteria have evolved symbiotic alliances in which the benefits to both parties are nearly equivalent. Bacteria are also able to employ the luminescence reaction for quorum sensing, which is sometimes referred to as quorum signalling or Quorum Sensing. Quorum sensing is a method of cell-to-cell communication that enables bacteria to detect, react to, and control gene expression in response to the density of bacterial cells.
The process of producing light by a chemical reaction that takes place within the cells of an organism is referred to as bioluminescence. This type of chemical luminescence reaction is one type of illumination reaction. Through this process, cold light is produced, which is a product of biological processes. Since less than 20% of the light generates heat, this type of light is referred to as cold light. During the chemical reaction, molecules of luciferin and luciferase are both implicated. Luciferin is the name given to the combination of chemicals and substrates that emit light. The oxidation of this light-emitting molecule is controlled by either the enzyme luciferase or a photo protein, which is a variant of luciferase in which the components for light emission are connected. Luciferase is a type of enzyme or catalyst that works in conjunction with the substrate to bring about a rapid chemical reaction. Luciferin that has been oxidized is the product of the reaction between the enzyme luciferase and luciferin that has been oxidized.

Bacteria that emit glowing light

When it comes to microorganisms, bioluminescent bacteria are the most widespread type. It is possible to find these minuscule organisms that generate light in both marine and terrestrial environments; nevertheless, the bulk of them are located in the waters of the ocean. There are various categories of bioluminescent bacteria, the most prominent of which are Vibrio, Photobacterium, and Aliivibrio categories.
As an illustration, Vibrio fischeri has symbiotic relationships with marine organisms such as the Hawaiian bobtail squid. The bacteria enter the light organ of the squid, which provides it with a form of camouflage
that is referred to as counter illumination. Through the use of this method, the squid can blend in with the moonlight from above, so concealing its profile from predators that are located below.
Photobacterium phosphoreum is yet another example that is worthy of mention. This particular bacterium may be discovered in the digestive tracts of marine organisms as well as on the surfaces of rotting fish. This phenomenon, which is commonly referred to as “milky seas,” is significantly influenced by these microorganisms.

Fungi that emit glowing light

Even though they are not as frequent as the species that are found in the bacterial and protist kingdoms, particular fungal species are capable of producing light. The majority of bioluminescent mushrooms grow in tropical and temperate forests, where they play significant roles in the decomposition processes that occur in these environments.
In 2015, it was found that the fungal luciferin and its precursor were found to be 3-hydroxyhispidin and hispidin, respectively, in four bioluminescent fungi: Mycena, Neonothopanus nambi, Armillaria borealis, Panellus stipticus, and citricolor. In 2017, the structure of the emitter oxyluciferin was shown through evidence that the molecule breaks down into caffeic acid when it comes in contact with water. (Ke & Tsai, 2022).
Most likely, the bioluminescent fungus that is the most well-known is Neonothopanus gardneri, which is indigenous to Brazil, also commonly referred to as the “ghost fungus.” The mycelium and fruiting bodies of it, emit a light that is bright greenish. Although the precise function of fungal bioluminescence is not yet known, it is possible that it may attract insects that aid in the dissemination of spores or that it may deter fungivores like insects.
There is also the Panellus stipticus, which is also referred to as the bitter oyster mushroom. This is another interesting example. The only populations of this species that contain bioluminescent characteristics are those found in North America; the European and Asian variations do not produce any light.

Research and Applications

A great number of scientific advancements and practical uses have resulted from the study of bioluminescent microbes, including the following:

Biotechnology has allowed for the isolation of the genes that are responsible for bioluminescence, notably those found in bacteria, which have then been utilized in the production of bioluminescent indicators. Scientists can measure gene expression, monitor cellular processes, and investigate the evolution of disease thanks to these markers, which are extremely helpful in a variety of fields of biological research.
In the field of environmental monitoring, biosensors are utilized to detect environmental toxins by the utilization of bioluminescent bacteria. It is possible to modify these organisms such that they light when they are in the presence of particular contaminants. This provides a method that is both quick and sensitive for evaluating the quality of water.
Bioluminescent imaging techniques have brought about a revolution in the field of medical research, particularly in the study of infectious diseases and cancer. Researchers can monitor the progression of viruses or cancer cells within living organisms in real time by tagging them with bioluminescent proteins. This allows them to monitor how effectively treatments are working.

Despite the progress that has been achieved in knowing about bioluminescent microorganisms, there are still a lot of questions that have not been solved. Researchers are currently focusing their attention on several different aspects of bioluminescence, including its evolutionary roots, the entire scope of its ecological significance, and the intricate metabolic pathways that are involved.
The development of bioluminescent bacteria in laboratory settings presents a substantial barrier despite its potential benefits. The capacity to examine a great number of species in depth is hindered by the fact that it is difficult to cultivate them in artificial settings. To overcome these challenges, it may be possible to make advancements in culturing techniques and environmental simulation.
In addition, the development of bioluminescent technologies that are environmentally friendly is another frontier. The creation of bioluminescent plants, which could function as natural light sources that do not require the use of electricity, is currently being investigated by researchers. This field has promise for environmentally friendly lighting solutions, even though it is still in its early stages.
The fascinating combination of. biology, chemistry, and ecology that bioluminescent bacteria represent is sure to captivate your attention. In addition to capturing the imagination of humans, these minuscule light-emitting organisms perform an important function in the habitats in which they are found, which range from the depths of the oceans to the canopy of the forest.
When we continue to solve the riddles of bioluminescence, we not only acquire a more profound comprehension of the natural world but also discover potential answers to the most important problems that the scientific community and the environment are currently facing. The study of these illuminating bacteria serves as a reminder that even the tiniest organisms can have a significant influence on our surrounding environment and on our comprehension of the concept of life itself.
In the vast tapestry of nature, bioluminescent bacteria stand out as awe-inspiring beacons of wonder. They shed light on the deep connections that exist between all living things and encourage future generations of scientists to investigate the hidden corners of our world.

R M S P RANATHUNGA

Reference

• Ke, H.-M. and Tsai, I.J. (2022) ‘Understanding and using fungal bioluminescence – recent progress and future perspectives’, Current Opinion in Green and Sustainable Chemistry, 33, p. 100570. doi:10.1016/j.cogsc.2021.100570.
• Stevani, C.V. et al. (2024) ‘The living light from fungi’, Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 58, p. 100654. doi:10.1016/j.jphotochemrev.2024.100654.
• https://education.nationalgeographic.org/resource/bioluminescence/

Microorganisms are everywhere, all around us, at all times. As you are currently reading this, microorganisms are living and crawling across your skin, helping you with digestion in your gut and floating and falling in the air around you. Every time we speak, we expel thousands of microbes into the air, and every time we eat, our food is dusted with a small seasoning of microbes.

Microorganisms are the reason for some of humanity’s greatest inventions, bread, cake, buns, beer, wine, yogurt, curd, etc. These little creatures are our long-distant ancestors, the first living organisms living eons before our existence, and will live for eons after our extinction. In many ways, they live both in and on us. More than 1.6 billion years ago bacteria capable of producing a lot of energy, using oxygen, was acquired by a larger cell.1 These bacteria are what we call mitochondria today; a bacterial descendant that lives in every cell in our body providing us with the energy that allows us to live our lives.

And yet these organisms so important to our survival and existence are invisible to us. Microorganisms exist on the scale of micrometers; 1 million times smaller than a meter. Although the existence of microorganisms, or microorganism-like creatures was hypothesized by many people across history, it was not until the man who could be described today as the first microbiologist, Antonie Philips van Leeuwenhoek, and his invention of the first microscope, that we had truly had evidence of their existence. Since that time many advances in microbiology have happened; such as the development of techniques to isolate and grow microorganisms in laboratories, the development of more powerful microscopes that allowed us to observe the size, shape, and behavior of microorganisms, the invention of even more powerful electron microscopes which allowed us to see the individual parts of cells, and the development of technology that allowed us to examine the molecules and genes (DNA molecules that store information on how to make proteins) that make these organisms who they are.

The study of microorganisms has been key to developing theories, such as that all organisms are made of cells, that many diseases are transmitted and caused by microorganisms, and that all organisms, micro, and macro, are related to each other through evolution. However, only the study of a few microorganisms can be credited with these discoveries, such as the bacteria Escherichia coli, baker’s yeast Saccharomyces cerevisiae, and the algae Chlamydomonas reinhardtii. Even within these species it is a few strains (genetically identical individuals) that can be credited such as the BY4741 strain in Saccharomyces cerevisiae. These microorganisms can be easily studied in laboratories by microbiologists because they have a unique set of features such as growing easily on nutrition rich environments in laboratories, growing fast, being inexpensive to grow and maintain, and whose growth, reproduction, physical characteristics, behavior, and genetics can be easily manipulated. Only a few microorganisms early in microbiological science fit these criteria and have now become what we call “model” organisms.

An example of this is the BY4741 isolate of Saccharomyces cerevisiae. This isolate is naturally single-celled, is similar to human cells (it has a nucleus), grows well in nutrition created in the lab, grows very quickly – reproduces every 90 minutes – and can be bred easily through sexual reproduction. BY4741 also can be easily genetically modified; it is easy for researchers to observe how genes work, insert new genes, and or stop existing genes from working
through relatively cheap and easy molecular tools. Saccharomyces cerevisiae has been used to understand how cells make proteins, how cells grow and divide, and to identify cancer genes in humans.

It should not be understated how much knowledge model organisms have contributed to microbiology, and how much more model organisms continue to provide. The depth of history and tools in existence concerning these organisms make them excellent for highly detailed, and complex studies. However, model organisms also create a unique set of problems and expose some of the current limitations of microbiology. Our current techniques of growing microorganisms only allow for a small fraction of microorganisms to be grown and identified in laboratories, and the other features that make a microorganism a “model” organism are not ubiquitous. In this way model organisms are not models for typical microorganism behaviors and all conclusions from studies of these organisms cannot be generalized.

Microbial diversity is a “known unknown”; that is we know that across the bacteria, fungi, and Protoctista kingdoms approximately 1 trillion species exist5, but of these, we only have evidence for approximately 100,000 through DNA identification5, and of those only approximately 10,000 have ever been cultured.5 Therefore these few model organisms cannot possibly represent the diversity of microorganisms, and current isolation and growth techniques based on model organisms will never allow for the isolation of all microorganisms.

Even within a species such as Saccharomyces cerevisiae the BY4741 isolate is only one of ~300 cultured isolates.2 Although the strain has contributed much to the field of genetics and molecular biology, it is of limited ecological significance. For example, most Saccharomyces cerevisiae isolates present a behavior known as flocculation, where the cell walls of individual yeast cells form strong bonds with each other, a behavior mostly absent in BY4741,3 Most other Saccharomyces cerevisiae isolates can grow well on many different types of sugars compared to BY47413, and BY4741 differs significantly from other strains in terms of the genes and the number of copies of those genes it possesses.3

For species such as Saccharomyces cerevisiae, other strains are being developed as model organisms, sometimes referred to as “emerging model organisms”, and soon we may have “model clades” – groups of related organisms characterized as well as existing model organisms. However, for organisms that do not grow using traditional laboratory techniques, new growing techniques need to be developed, along with the use of new sampling techniques such as DNA sequencing.

The successes of model organisms themselves and their economic importance create a bias both in terms of funding and research interest towards experiments using these organisms, reducing the funding and interest in non-model organisms. This is detrimental to microbiology as a whole as much knowledge is lost and can only be remedied by a better incentive structure to pursue non-model organisms.

The study of non-model organisms is essential to the further understanding of evolutionary and ecological relationships but is also of major economic importance. Phytoplasma are a pathogenic group of microorganisms that cause devastating crop diseases leading to massive economic losses that are poorly studied and are currently unable to be cultured in laboratories. The polymerase enzyme from Thermus aquaticus has been essential to the industry of biotechnology which now is estimated to be a $1.55 trillion industry.4

The knowledge learned from model organisms, and the tools they’ve developed such as genetic engineering, phylogenetics, and high throughput sequencing, should be used as a basis to expand outwards and explore microbial diversity. More complex systems of growth outside of agar
plates/test tubes and liquid broth should be developed to understand and characterize the true diversity and complexity of growth behaviors.

For many microbiologists, model organisms are already explored territory, and although they may still have much to give, non-model organisms are exciting new frontiers to explore. Hopefully, in the future, we will have a much broader and fuller array of knowledge with regards to the microbial diversity that our world has to offer.

MHBKM Bandara

References:

1. Prasad, B., Uniyal, S. N., & Asher, R. (2005). Organic-walled microfossils from the Proterozoic Vindhyan Supergroup of son valley, Madhya Pradesh, India. Journal of Palaeosciences, 54((1-3)), 13–60. https://doi.org/10.54991/jop.2005.68

2. Cromie, G. A., Hyma, K. E., Ludlow, C. L., Garmendia-Torres, C., Gilbert, T. L., May, P., Huang,
A. A., Dudley, A. M., & Fay, J. C. (2013). Genomic sequence diversity and population structure of Saccharomyces cerevisiae assessed by Rad-Seq. G3 Genes|Genomes|Genetics, 3(12), 2163–2171. https://doi.org/10.1534/g3.113.007492

3. Cubillos, F. A., Louis, E. J., & Liti, G. (2009). Generation of a large set of genetically tractable haploid and diploid Saccharomyces cerevisiae strains. FEMS Yeast Research, 9(8), 1217–1225. https://doi.org/10.1111/j.1567-1364.2009.00583.x

4. Biotechnology market size, Share & Growth Report, 2030. Biotechnology Market Size, Share & Growth Report, 2030. (n.d.). https://www.grandviewresearch.com/industry-analysis/biotechnology- market

5. Locey, K. J., & Lennon, J. T. (2016). Scaling Laws Predict Global Microbial Diversity. https://doi.org/10.7287/peerj.preprints.1451

Fermentation is a magical process that transforms simple ingredients into flavorful, nutritious, and sometimes even surprising foods and beverages. From bread and cheese to yogurt and beer, fermentation has been a part of human culture for thousands of years. But what exactly is fermentation, and how do microbes play a role in this transformative process? Let’s dive into the science behind fermentation and discover how these tiny organisms work their magic.

What is Fermentation?

At its core, fermentation is a metabolic process in which microbes convert sugars into other compounds, such as alcohol, acids, and gases. This process occurs in the absence of oxygen (anaerobic conditions) and is primarily carried out by bacteria and yeast. The resulting products of fermentation not only preserve food but also enhance its flavor, texture, and nutritional value.

Types of Fermentation

There are several types of fermentation, each producing different end products. Lactic acid fermentation is carried out by lactic acid bacteria, which convert sugars into lactic acid. This type of fermentation is behind the making of yogurt, sauerkraut, kimchi, and pickles. Alcoholic fermentation involves yeasts, particularly Saccharomyces cerevisiae, converting sugars into alcohol and carbon dioxide (CO2), which is used in brewing beer, winemaking, and baking bread. Acetic acid fermentation involves bacteria converting ethanol (alcohol) into acetic acid, producing vinegar. Butyric acid fermentation involves certain bacteria converting sugars into butyric acid, carbon dioxide, and hydrogen, contributing to the distinctive flavor of some cheeses.

● Lactic Acid Fermentation

Lactic acid fermentation is one of the most common types of fermentation. It is used in the production of a variety of foods such as yogurt, kefir, sauerkraut, kimchi, and pickles. In this process, lactic acid bacteria convert sugars, primarily lactose, into lactic acid. The production of lactic acid lowers the pH of the food, creating an acidic environment that inhibits the growth of harmful bacteria and preserves the food. This type of fermentation also enhances the nutritional profile of the food by increasing the availability of certain vitamins and minerals.

● Alcoholic Fermentation

Alcoholic fermentation is the process used to produce alcoholic beverages such as beer, wine, and spirits. It is also used in the production of bread. During alcoholic fermentation, yeasts convert sugars into alcohol (ethanol) and CO2. In beer production, for example, malted barley is mixed with water to create a mash. The mash is then heated to activate enzymes that convert the starches in the barley into fermentable sugars. Yeast is then added to the mash, and the fermentation process begins. The CO2 produced during fermentation gives beer its carbonation, while the alcohol provides its intoxicating effects.

● Acetic Acid Fermentation

Acetic acid fermentation is used to produce vinegar. This process involves the conversion of ethanol into acetic acid by acetic acid bacteria. Vinegar production typically begins with the fermentation of sugars into ethanol, followed by a secondary fermentation in which acetic acid bacteria convert the ethanol into acetic acid. This process can be carried out using a variety of raw materials, including wine, cider, and rice.

● Butyric Acid Fermentation

Butyric acid fermentation is less common but is used in the production of certain cheeses and other fermented foods. In this process, bacteria convert sugars into butyric acid, CO2, and hydrogen. Butyric acid has a strong, pungent smell and contributes to the distinctive flavors of some cheeses, such as Parmesan and Swiss cheese.

The Role of Microbes in Fermentation

Microbes are the real stars of the fermentation process. They are responsible for breaking down the sugars in ingredients and transforming them into new, flavorful, and beneficial compounds. Let’s look at how some common fermented foods are made and the microbes involved.

Yogurt

Yogurt is a popular fermented dairy product made by adding specific strains of bacteria, typically Lactobacillus bulgaricus and Streptococcus thermophilus, to milk. These bacteria ferment the lactose (milk sugar) into lactic acid, which lowers the pH of the milk, causing it to thicken and develop a tangy flavor. The acidic environment also helps preserve the yogurt and supports gut health by promoting beneficial bacteria in the digestive system.

Bread

Breadmaking involves the fermentation of dough by yeast, primarily Saccharomyces cerevisiae. When yeast ferments the sugars in flour, it produces CO2 and alcohol. The carbon dioxide gets trapped in the dough, causing it to rise and giving bread its light, airy texture. The alcohol evaporates during baking, leaving behind the delicious flavour and aroma of freshly baked bread.

Cheese

Cheese-making is a complex process that involves the fermentation of milk by lactic acid bacteria. These bacteria convert lactose into lactic acid, which curdles the milk proteins, forming curds and whey. The curds are then processed, aged, and sometimes inoculated with specific molds or bacteria to develop different textures and flavors. For example, Penicillium roqueforti is used to produce blue cheese, while Brevibacterium linens contribute to the distinctive aroma of Limburger cheese.

Sauerkraut and Kimchi

Both sauerkraut and kimchi are made by fermenting cabbage with lactic acid bacteria. The natural bacteria present on the cabbage leaves, including Lactobacillus plantarum and Leuconostoc mesenteroides, convert the sugars in the cabbage into lactic acid. This process not only preserves the cabbage but also enhances its flavor, making it tangy and slightly sour. The fermentation also increases the bioavailability of nutrients, making these foods even more nutritious.

Beer and Wine

The production of beer and wine relies on alcoholic fermentation by yeast. In beer making, yeast ferments the sugars in malted barley, producing alcohol and carbon dioxide. Hops are added for bitterness and flavor, and the resulting beverage is carbonated and refreshing. In winemaking, yeast ferments the sugars in grape juice, producing alcohol and CO2. The type of grapes and the fermentation process contribute to the wide variety of wine flavors and styles.

Health Benefits of Fermented Foods

Fermented foods are not only delicious but also offer numerous health benefits. Here are some of the key advantages:

● Improve Digestion
Fermented foods are rich in probiotics—beneficial bacteria that support a healthy gut microbiome. These probiotics help to balance the gut flora, improving digestion and nutrient absorption. They can also alleviate symptoms of digestive disorders like irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD).

● Enhance Nutrient Absorption
Fermentation can increase the bioavailability of certain nutrients, making them easier for our bodies to absorb. For example, the fermentation of dairy products can increase the levels of B vitamins, calcium, and other essential nutrients.

● Immune System Support
A healthy gut microbiome is crucial for a strong immune system. Probiotics in fermented foods can enhance immune function by stimulating the production of antibodies and promoting the activity of white blood cells.

● Antioxidant Properties
Some fermented foods, such as kimchi and sauerkraut, are rich in antioxidants that help to protect cells from damage caused by free radicals. These antioxidants can reduce inflammation and lower the risk of chronic diseases.

● Preservation and Safety
Fermentation naturally preserves food by creating an acidic environment that inhibits the growth of harmful bacteria. This means that fermented foods can be stored for longer periods without spoiling, reducing food waste and increasing food security.

The Art and Science of Fermentation at Home

Fermenting foods at home is a rewarding and fun way to explore the science of microbes and create delicious, nutritious foods. Here are some tips to get started:

Choosing Ingredients
Start with fresh, high-quality ingredients. The quality of your raw materials will directly impact the flavor and success of your fermentation.

Cleanliness
Maintain a clean environment to prevent contamination by unwanted microbes. Sterilize your equipment and wash your hands thoroughly before handling ingredients.

Controlling Temperature
Most fermentation processes require specific temperature ranges. For example, yogurt ferments best at around 110°F (43°C), while sauerkraut ferments at room temperature. Ensure that you maintain the right temperature for the type of fermentation you are performing.

Monitoring and Patience
Fermentation is a slow process that requires time. Regularly check your fermenting foods for signs of progress, such as bubbling, changes in texture, and the development of characteristic flavors and aromas.

Experimentation
Don’t be afraid to experiment with different ingredients and techniques. Fermentation is both an art and a science, and there’s plenty of room for creativity. Try adding spices, herbs, or other flavorings to customize your ferments.

Conclusion

Fermentation is a fascinating process that harnesses the power of microbes to transform simple ingredients into complex, flavorful, and nutritious foods. From the tangy taste of yogurt to the effervescent bubbles of beer, fermented foods are a testament to the incredible capabilities of microorganisms. By understanding the science behind fermentation and experimenting at home, we can appreciate the ancient art of fermentation and enjoy its many benefits in our modern lives.
So, the next time you savor a piece of cheese, sip a glass of wine or bite into a crunchy pickle, remember the tiny microbes that made it all possible. They are the unsung heroes working behind the scenes, turning ordinary ingredients into extraordinary culinary delights.

Isuri Pathirana

2023/AM/19

References:

1. Madigan, M.T., Martinko, J.M., Stahl, D.A., & Clark, D.P. (2012). Brock Biology of Microorganisms (13th ed.). Benjamin Cummings.
2. Prescott, L.M., Harley, J.P., & Klein, D.A. (2005). Microbiology (6th ed.). McGraw-Hill.
3. Ray, B., & Bhunia, A. (2007). Fundamental Food Microbiology (4th ed.). CRC Press.
4. Hutkins, R.W. (2006). Microbiology and Technology of Fermented Foods. Blackwell Publishing.
5. Wood, B.J.B., & Holzapfel, W.H. (1995). The Lactic Acid Bacteria: The Genera of Lactic Acid Bacteria. Springer.
6. Fox, P.F., McSweeney, P.L.H., Cogan, T.M., & Guinee, T.P. (2004). Cheese: Chemistry, Physics and Microbiology (3rd ed.). Academic Press.
7. Steinkraus, K.H. (1996). Handbook of Indigenous Fermented Foods (2nd ed.). CRC Press.
8. Bamforth, C.W. (2009). Beer: Tap into the Art and Science of Brewing (2nd ed.). Oxford University Press.
9. Gill, H.S., & Guarner, F. (2004). Probiotics and Human Health: A Clinical Perspective. Postgraduate Medical Journal, 80(947), 516-526.
10. Tamime, A.Y. (2009). Fermented Milks. Wiley-Blackwell.
11. Sanders, M.E. (2008). Probiotics: Definition, Sources, Selection, and Uses. Clinical Infectious Diseases, 46(Supplement_2), S58-S61.
12. Rhee, S.J., Lee, J.E., & Lee, C.H. (2011). Importance of lactic acid bacteria in Asian fermented foods. Microbial Cell Factories, 10(S1), S5.
13. Adams, M.R., & Nout, M.J.R. (2001). Fermentation and Food Safety. Springer.
14. Farnworth, E.R. (2008). Handbook of Fermented Functional Foods (2nd ed.). CRC Press.
15. Katz, S.E. (2012). The Art of Fermentation: An In-Depth Exploration of Essential Concepts and Processes from Around the World. Chelsea Green Publishing.

Cinnamon has been a well-known crop worldwide for centuries not only because it is a spice but also because of its antioxidant, anti-inflammatory, and antimicrobial properties. In Sri Lanka Cinnamomum zeylanicum (“Ceylon cinnamon/true cinnamon”) is a native plant of the country and plays an important role in the Sri Lankan export market acquiring a significant amount of foreign exchange for the country. According to a reviewed article published in Plants, People, and Planet on 8th April 2021, Because of its superior quality, low concentration of the hazardous chemical ingredient coumarin, which is found in Cassia cinnamon in quite high concentrations, and its chemical makeup, Ceylon cinnamon is relatively pricey. Therefore, over 350,000 families rely on the Sri Lankan Cinnamon industry, producing various types of commercial goods such as; cinnamon tea, cinnamon sticks, and cinnamon oil. But, recently because of low yield, the Sri Lankan cinnamon export industry has not reached its potential income.
Mainly, cinnamon bark is the major part of the tree used to produce many more products, and enhancing the bark yield is a very important aspect. Cinnamon is kept as a bush through coppicing and a quilling-peeling process is used to obtain the bark. Coppicing can be done from the fourth year of planting. Bark extraction works best with uniformly brown shoots with a 1.2 to 2.0 cm thickness and shoots with this thickness of the bark are dried before commercial use.

There are several ways to enhance the cinnamon yield. According to an article published by LSS Patirana in 2007, under natural conditions, the coppicing approach used in commercial cinnamon cultivation produces many stems with a substantially smaller girth from a single plant during a single harvest. This approach shortens the time needed for harvesting while also making the task of harvesting and processing very simple. Coppicing is thought to increase a crop’s ultimate biomass, which, in the case of cinnamon increases the crop’s total bark production. according to a study done by Pathiratna and Perera carried out on an 80-year-old plant, they found that eventually, a single plant can generate several stems as a result of ongoing coppicing, which results in roughly 5-7 stems per plant. The results of a recent study conducted by H.N. Athulgamage showed that the quantity of harvestable stems of cinnamon plants is also influenced by the type of planting material, the interaction effect between planting material, and spatial pattern.

Currently many studies are being conducted to enhance the bark yield of this Cinnamomum zeylanicum plant. Soil is the major nutritional source that determines the plant growth rate. A study on “Raising cinnamon seedlings by using vermicompost on “subsoil” conducted by Ishara and the team at the Division of Soil and Plant Nutrition, Cinnamon Research Station, Palolpitiya, Thihagoda, Matara in the WL2a Agro-Ecological Region in 2013, revealed that higher content of Total N, Available P, Exchangeable K, and Organic matter in vermicompost improved the soil’s physical and chemical properties and also supported the growth performance of cinnamon seedlings. The reason for this growth rate increment experimented by N.Q.Aracon and the team in 2006, found that the reason for increasing the growth rate of plants is because of the interaction between  earthworms in vermin compost and microorganisms influencing soil organic matter decomposition and soil enzymatic activities. 

Yaacov Okon noted that most growth-promoting microorganisms in soil enhance yield through various mechanisms, including the provision of combined nitrogen to plants. A study by R. Swarna Priya and the team at Tamil Nadu Agricultural University focused on the effect of biofertilizers on cinnamon growth and yield. They found that the soil type was clay-rich with moderate to high acidity and a moisture-holding capacity of 40 to 50%. Available phosphorus was very low (10 kg/ha), while nitrogen and potash levels were 150 kg/ha and 20 kg/ha, respectively.
Due to the low levels of available nitrogen (N) and potassium (K), Vesicular-Arbuscular Mycorrhiza (VAM) and Azospirillum were incorporated into the treatments with soil. This Vesicular-Arbuscular Mycorrhiza (VAM) is a type of beneficial fungus that forms a symbiotic relationship with plant roots. They recorded their observations on plant height, stem girth, number of branches, and bark yield per tree.

Several cinnamon trees were treated annually with 250 grams of nitrogen (N), 130 grams of phosphorus (P), and 250 grams of potassium (K) per tree, along with 3 kilograms of Vesicular Arbuscular Mycorrhiza (VAM) per tree. This treatment resulted in the maximum recorded plant height of 2.75 meters and a stem girth of 13.0 centimeters. Nitrogen is a crucial nutrient for plant growth, playing key roles in photosynthesis, protein synthesis, and overall vegetative growth.  Potassium is essential for various physiological processes, including water regulation, enzyme activation, and photosynthesis. The increased amounts of these nutrients provided an optimal environment for the trees to grow more vigorously, resulting in greater plant height and stem girth.
VAM enhances nutrient uptake, particularly phosphorus, and improves water absorption. This symbiosis leads to better root development, increased nutrient efficiency, and overall improved plant health. The addition of VAM at 3 kilograms per tree boosted the effectiveness of the applied fertilizers, further enhancing growth.

They also found that adding VAM increased the amount of branching of cinnamon trees. With the application of 250 grams of nitrogen, 130 grams of phosphorus, 250 grams of potassium, and 3 kilograms of Vesicular-Arbuscular Mycorrhiza (VAM) per tree, the maximum bark yield of 2.050 kg per tree was obtained during the second harvest. The treatments that produced the maximum bark output (2.050 kg/tree) included VAM, and bark yield increased significantly in other VAM treatments as well.  
This illustrates how VAM has a significant impact on increasing cinnamon bark output. The relationship with Vesicular-Arbuscular Mycorrhiza (VAM) has been shown to considerably enhance cinnamon bark production and overall plant growth. This study highlights the importance of incorporating VAM into cinnamon’s nutrient management strategy to promote growth and increase bark yield. This method is particularly suitable for the Sri Lankan cinnamon industry, and further thorough studies are needed to fully understand and optimize its benefits.

The findings of this study are highly relevant to the Sri Lankan cinnamon industry. Incorporating VAM into the nutrient management strategy for Ceylon cinnamon can help address the issue of declining yields and maximize the economic potential of this vital crop. Given the significant role of cinnamon in the national economy and the livelihoods of many Sri Lankan families, adopting this approach can lead to substantial improvements in both productivity and income. However, a thorough study tailored to local conditions is recommended to optimize the use of VAM and other biofertilizers for the best results in Sri Lankan cinnamon cultivation.
K.A.M.V.Kasthurirathna

References
Suriyagoda, L., Mohotti, A.J., Vidanarachchi, J.K., Kodithuwakku, S.P., Chathurika, M., Bandaranayake, P.C., Hetherington, A.M. and Beneragama, C.K., 2021. “Ceylon cinnamon”: Much more than just a spice. Plants, People, Planet, 3(4), pp.319-336.
Arancon, C.A. Edwards, P. Bierman, Influences of vermicomposts on field strawberries: Part 2. Effects on soil microbiological and chemical properties, Bioresource Technology, Volume 97, Issue 6, 2006,
Pathiratna, L.S.S., 2007. Factors affecting bark yield components of cinnamon.
Aluthgamage, H.N., Fonseka, D.L.C.K. and Benaragama, C.K., 2021. Study the cinnamon (Cinnamomum verum J. Presl) yield indices under modified planting systems.
Priya, R.S., Joshua, J.P., Justin, C. and Jayasekhar, M., 2007. Effect of biofertilizers on the growth and yield of cinnamon (Cinnamomum zeylanicum Blume). Indian Journal of Agricultural Research, 41(4), pp.310-312.
Madushika Wariyapperuma, W.A.N., Kannangara, S., Wijayasinghe, Y.S., Subramanium, S. and Jayawardena, B., 2021. Fungal pretreatment to enhance the yield of phytochemicals and evaluation of α‐amylase and α‐glucosidase inhibition using Cinnamomum zeylanicum (L.) quills pressurized water extracts. Letters in Applied Microbiology, 72(2), pp.196-205.
Aluthgamage, H., 2023. Enhancement of high-quality cinnamon quill production through agronomic approaches: a review. Academia Biology, 1(1).
Okon, Y. and Baker, R., 1987. Microbial inoculants as crop-yield enhancers. Critical reviews in biotechnology, 6(1), pp.61-85.
Liyanage, I., Samaraweera, S. and Mapa, R.B., USE OF VERMI-COMPOST ENRICHED SUB SOIL AS AN ALTERNATIVE TO TOP SOIL IN RAISING CINNAMON SEEDLINGS.

When we think about growing healthy plants, we usually focus on sunlight, water, and good soil. But did you know that fungi play a crucial role in helping plants thrive? From traditional farming practices to modern agricultural innovations, fungi have played a significant role in shaping how we cultivate crops. In this article, we will explore different kinds of fungi that are beneficial to plants, their uses by gardeners and farmers, and how they help plants grow stronger and healthier.

Fungi are a group of organisms that include yeasts, molds, and mushrooms. They are distinct from plants and animals, forming their unique kingdom of life. Fungi play diverse roles in the ecosystem, from breaking down dead organic matter to forming symbiotic (mutually beneficial) relationships with plants.

Mycorrhizal Fungi: The Superheroes of Soil
Mycorrhizal fungi form a symbiotic relationship with plant roots, benefiting both parties. These fungi attach to the roots and extend deep into the soil, forming a vast network of filaments known as mycelium. This network acts as an extension of the plant’s root system, improving the efficient absorption of water and nutrients, especially phosphorus. In return, the plant provides the fungi with sugars and other carbohydrates produced via photosynthesis. This mutualistic relationship promotes plant growth, enhances soil structure, and increases plant resistance to diseases and environmental stresses.

Decomposer Fungi: Nature’s Recyclers
Decomposer fungi break down dead organic matter, such as fallen leaves and wood, turning them into nutrient-rich soil. This process, known as decomposition, releases essential nutrients back into the soil, making them available for plants to uptake. These fungi play a crucial role in nutrient cycling and maintaining soil fertility.

Endophytic Fungi: Plant Protectors
Fungi with biocontrol abilities can enhance plant disease resistance. For instance, Trichoderma species are well-known for their ability to outcompete pathogenic fungi in the same ecological niche. They can also activate plant defense mechanisms, making them more resistant to infections. This natural method of disease management reduces the need for synthetic pesticides, which aligns with sustainable agriculture practices.
Endophytic fungi live inside plant tissues without causing harm. They can produce chemicals that protect plants from pests and diseases. Additionally, these fungi can help plants tolerate stressful conditions, such as drought or poor soil quality, by boosting their resilience. Fungi can also decompose contaminants and toxins in the soil through bioremediation. They transform pesticides, heavy metals, and petroleum pollutants into harmless byproducts. These bioremediation processes help in the restoration of soil health in polluted regions, reclaiming lands for agricultural use, and reducing environmental hazards.

Climate Change Flexibility
Fungi can mitigate the impacts of climate change on agriculture. For instance, mycorrhizal fungi can help plants cope with environmental stresses such as drought, salinity, and extreme temperatures. Fungi help maintain steady yields despite changing climatic conditions, and thereby enhances food security and livelihoods globally.

Enhances the Crop Yields
Research indicates that incorporating fungi into agricultural practices can increase crop yields. Fungi improve overall plant health and productivity by enhancing nutrient uptake, increasing disease resistance, and promoting healthier soil conditions. This benefit is gaining recognition as farmers look for sustainable ways to increase yields while minimizing environmental impact.

Inoculating with Mycorrhizal Fungi
Fungal inoculants serve as natural alternatives to synthetic inputs, making them ideal for organic agriculture. Organic farmers often use fungal inoculants, which contain beneficial fungi, to enhance soil biodiversity and plant health. These inoculants are applied to seeds, roots, or directly into the soil, providing a sustainable way to increase crop yields without relying on synthetic fertilizers or pesticides.
Gardeners and farmers can introduce mycorrhizal fungi to their soil or plants by adding spores or fungal material to the soil or directly to plant roots. Inoculants are available in various forms, including powders, granules, and liquid solutions. By incorporating these beneficial fungi, plants can establish a strong partnership early on, resulting in improved growth and health.

Composting with Fungi
Incorporating decomposer fungi into compost piles can accelerate the decomposition process and enhance the nutrient content of compost. Adding materials like straw, wood chips, and fallen leaves can encourage fungal growth in compost, resulting in a nutrient-rich soil amendment for gardens and farms.
Mycorrhizal fungi, specifically improves soil structure and water retention. Their hyphae form a network that binds soil particles together, resulting in aggregates that improve soil aeration and water infiltration. This increases the soil’s ability to retain moisture, which is especially beneficial in drought-prone areas or during dry spells. Improved soil structure also reduces erosion, protecting valuable topsoil and encouraging sustainable land management practices.

Biofertilizers and Biopesticides
Some fungi are used to create biofertilizers and biopesticides. Biofertilizers made from fungi can enhance soil fertility and plant nutrition, while fungal biopesticides naturally control harmful pests and diseases without chemical intervention. These sustainable solutions benefit both the environment and crop production.

Future Advancement with fungi in plant cultivation
Fungi have huge potential in agriculture, reaching beyond existing approaches. Researchers are investigating novel fungal strains and their applications to enhance plant health and soil quality. Biotechnology advancements provide bespoke treatments, such as unique fungal inoculants to meet specific crop demands or climatic conditions. These innovations have the potential to address global food security challenges in an eco-friendly manner.

Education and Awareness
Raising awareness of the agricultural benefits of fungi is crucial for their broad adoption. Educational campaigns and outreach programs can raise awareness among farmers, policymakers, and consumers about the importance of fungi in sustainable food production. We can foster an environment conducive to integrating fungal-based solutions into conventional agricultural practices by increasing awareness and appreciation for fungi’s contributions.
Fungi serve as valuable allies in sustainable agriculture, providing several advantages that extend far beyond traditional agricultural methods. Fungi play a crucial role in shaping the future of global food systems by enhancing nutrient absorption, and disease resistance, as well as improving soil health and climate resilience.
As ongoing research and innovations continue to uncover their potential, incorporating fungi into agricultural practices hold promise for promoting environmental stewardship and ensuring food security. Raise awareness about the benefits of fungi in agriculture to encourage wider adoption. Educational campaigns and outreach programs can raise awareness among farmers, policymakers, and consumers about the importance of fungi in sustainable food production. We may create a favourable atmosphere for incorporating fungal-based solutions into mainstream agricultural methods by increasing awareness and appreciation for fungi’s contributions
Fungi are important allies in plant cultivation, offering numerous benefits from enhancing nutrient absorption and soil health to managing pests and diseases. By understanding and utilizing the potential of fungi, gardeners and farmers can cultivate healthier, more resilient plants while promoting a sustainable and balanced ecosystem. Next time you oversee your garden or crops, remember that these incredible organisms are working silently beneath the surface, helping in the thriving of your plants.

By Oshanthi Perera

References
Banjare, K. (2020, June 9). Introduction of fungi in plant pathology. Agri Eduteck. https://eduteck97.blogspot.com/2020/06/introduction-of-fungi-in-plant-pathology.html
Giehl, A., dos Santos, A. A., Cadamuro, R. D., Tadioto, V., Guterres, I. Z., Prá Zuchi, I. D., Minussi, G. do A., Fongaro, G., Silva, I. T., & Alves, S. L., Jr. (2023). Biochemical and biotechnological insights into fungus-plant interactions for enhanced sustainable agricultural and industrial processes. Plants, 12(14), 2688. https://doi.org/10.3390/plants12142688
Karlsruhe Institute of Technology. (2016, October 19). How plants make friends with fungi. Science Daily. https://www.sciencedaily.com/releases/2016/10/161019100936.htm
McGinnis, M. R., & Tyring, S. K. (1996). Introduction to mycology. University of Texas Medical Branch at Galveston.
Odoh, C. K., Eze, C. N., Obi, C. J., Anyah, F., Egbe, K., Unah, U. V., Akpi, U. K., & Adobu, U. S. (2020). Fungal biofertilizers for sustainable agricultural productivity. In Fungal Biology (pp. 199–225). Springer International Publishing.
Roth, M. G., Westrick, N. M., & Baldwin, T. T. (2023). Fungal biotechnology: From yesterday to tomorrow. Frontiers in Fungal Biology, 4. https://doi.org/10.3389/ffunb.2023.1135263
Singh, M., Chauhan, A., Srivastava, D. K., & Singh, P. K. (2024). Unveiling arbuscular mycorrhizal fungi: the hidden heroes of soil to control the plant pathogens. Archiv Für Phytopathologie Und Pflanzenschutz, 57(6), 427–457. https://doi.org/10.1080/03235408.2024.2368112

Farmers have been using herbicides to manage weeds for many years. As a result of over-dependence on chemical weed control techniques, these weeds have become resistant to several herbicides creating superweeds. Due to their resistance to numerous herbicides, these persistent enemies make conventional weed control techniques useless. For instance, Roundup, one of the most widely used herbicides worldwide, contains glyphosate, against which more than 35 distinct weed species have become resistant. Wild oats, pigweed, and kochia are the other weeds resistant to glyphosate. The emergence of superweeds threatens crop yields and compels farmers to use powerful herbicides, which drives the cycle of resistance even further.
On the other hand, super microbes are beneficial microorganisms such as bacteria, fungi, and viruses that have improved capacities to support plant growth, boost soil health, or fight plant diseases. These microorganisms are essential to sustainable agriculture because they offer natural alternatives to chemical inputs.
Superweeds evolve over a period of time and their emergence is influenced by numerous factors. One major factor is the overuse of herbicides. Strong selection pressure is produced when the same herbicides are applied over wide areas regularly. To survive and procreate, weeds with naturally occurring genetic variations that allow them to withstand the herbicide pass on their resistance to subsequent generations. The next factor to consider is mode of action. The majority of herbicides work by concentrating on the biological mechanism of a specific weed. Hence, if weeds develop resistance to that particular mode of action, the herbicide becomes ineffective. Monoculture farming practices are another crucial factor. A single crop variety is frequently planted across a wide area in large-scale farming. This makes the environment consistent and beneficial for some weeds, making it easier for resistant populations to grow.

Agricultural Challenges Raised by Superweeds:
   • Herbicide Resistance: Superweeds put traditional weed management methods at jeopardy and demand the application of multiple herbicides or alternative techniques.
   • Increase in expenses: It gets considerably more difficult to control these weeds and may be necessary for farmers to use larger amounts of herbicide, apply them more frequently, or convert to more expensive herbicides entirely.
   • Yield Losses: If superweeds are allowed to spread, they may compete with crops for nutrients, sunlight, and water, resulting in lower yields and financial losses for farmers.
   • Threat to Food Security: If weeds are not controlled effectively, they can significantly reduce crop productivity, which could lead to an increase in food prices and a risk to food security.
   • Environmental Concerns: Increased use of herbicides for eliminating superweeds can lead to the development of herbicide resistance in weeds, soil degradation, disruption of ecosystems, and damage to beneficial insects and other creatures.

Super microbes are incredibly promising, particularly in the battle against superweeds. They offer enormous potential in several crucial areas. One such field is biocontrol and disease suppression. Super microbes provide biocontrol solutions against plant diseases and inhibit them by regulating induced systemic resistance in plants and using strategies such as competition for nutrients and antibiosis chemicals. Super microbe-based pesticides may attack particular pests or weeds while causing the least harm to other beneficial organisms. Nutrient cycling is the next key area. By enhancing soil fertility and crop nutrition through processes like phosphate solubilization and nitrogen fixation, some microorganisms increase the availability of nutrients in soils. Climate resilience comes next. Microbes can help crops endure environmental conditions like heat and drought by increasing the efficiency of water and nutrient uptake in plants. Reduced reliance on chemicals is another area. Super microbes provide a long-term benefit to soil health by reducing the risk of resistance development in pests and providing a sustainable alternative to chemical-based remedies.

How super microbes fight against superweeds:
   • Bioherbicides: Some microbes produce toxins that kill certain weeds but do not have an impact on crops. With minimal negative effects on the environment and beneficial organisms, they provide a targeted method of controlling weeds.
   • Pathogen Power: Scientists are discovering microorganisms that function as native pathogens for particular types of weeds. These microscopic creatures can biologically combat superweeds by infecting and killing the weeds.
   • Losing the Balance: Some bacteria can interfere with the equilibrium that exists between weeds and the helpful bacteria that support their growth. These super microbes may decrease their competitive advantage by changing the microbiome of the weed.

Super microbes are beneficial over conventional weed-control techniques, especially chemical herbicides, in many ways. They are Environmentally Friendly. Super microbes decompose naturally and present a low risk of soil or water contamination compared to chemical pesticides, thus, supporting a healthier soil ecosystem. In addition, they are weed-specific as opposed to chemical herbicides. By focusing on particular weeds, bioherbicides, and microbial control agents can reduce damage to beneficial insects and other organisms in the field. This encourages a more balanced agricultural ecology and biodiversity. Super microbes also lessen the need for chemicals. They provide a long-term substitute for chemical herbicides, promote soil health, and disrupt the cycle that leads to the development of pesticide-resistant superweeds.

What’s ahead
Superweeds are still ahead in the fight. Although super microbes have a lot of potential, there are some issues to take into account:
   • Specificity: It’s critical to create pathogens and bioherbicides that selectively destroy certain weeds without harming crops.
   • Efficacy in Real-World Environments: Super microbes that thrive in well-regulated laboratory environments would not necessarily be effective in real-world environments.
   • Extensive Application: To integrate super microbes into current agricultural processes in a user-friendly and affordable manner, more research and development is needed.

Super microbes by themselves cannot defeat superweeds. Innovations and strategies including Integrated Pest Management (IPM), biological weed control, and microbial consortia are required to achieve success in controlling superweeds. IPM uses a combination of mechanical, cultural, and biopesticides derived from super microorganisms to control pest and disease stresses. By making use of the synergistic interactions between beneficial bacteria in microbial consortia, agricultural ecosystems may become more resilient and successful. However, to feed a growing global population, the constant challenge is to harness innovation while preserving environmental and economic sustainability.
In summary, the conflict between super microbes and superweeds highlights the necessity of innovative, long-term solutions in agriculture. Using bio-based substitutes and implementing them into integrated farming methods presents practical possibilities to effectively address these issues and promote sustainable development.

Uvini Rodrigo

References:
   • Directorate-General for Education, Youth, Sport and Culture (European Commission) , The super microbes! Publications Office of the European Union, 2021. Accessed: Jun. 20, 2024. [Online]. Available: https://op.europa.eu/en/publication-detail/-/publication/a6f78d5e-5d54-11ec-9c6c-01aa75ed71a1
   • M. Hasan, M. S. Ahmad-Hamdani, A. M. Rosli, and H. Hamdan, “Bioherbicides: an EcoFriendly Tool for Sustainable Weed Management,” Plants, vol. 10, no. 6, p. 1212, Jun. 2021, doi: https://doi.org/10.3390/plants10061212.
   • R. Ofosu, E. D. Agyemang, A. Márton, G. Pásztor, J. Taller, and G. Kazinczi, “Herbicide Resistance: Managing Weeds in a Changing World,” Agronomy, vol. 13, no. 6, p. 1595, Jun. 2023, doi: https://doi.org/10.3390/agronomy13061595.
   • S. O. Duke, “Why are there no widely successful microbial bioherbicides for weed management in crops?,” Pest Management Science, vol. 80, no. 1, pp. 56–64, Jan. 2024, doi: https://doi.org/10.1002/ps.7595.

Sustainable agriculture, or farming that satisfies present food demands without jeopardizing the capacity of future generations to fulfil their own, has gained popularity in recent years. The use of microorganisms in sustainable agriculture is one of the most fascinating and promising fields. Invisible to the human eye, these microscopic organisms are essential to the development of productive, ecologically friendly, and wholesome farming systems.

Microbes are tiny living things that are found all around us. Also known as microorganisms, they are too small to be seen by the naked eye. They live in water, soil, and in the air. The human body is home to millions of these microbes too. While some microbes can cause diseases, many others are beneficial and essential for life. In agriculture, beneficial microbes are becoming the unsung heroes of sustainable practices.

Figure 01: Types of Microbes

Soil is not just dirt; it’s a living ecosystem teeming with microbial life. Healthy soil is fundamental to sustainable agriculture, and microbes are crucial for maintaining soil health. Here’s how they contribute:

1. Nutrient Cycling: Soil microbes play an important role in nutrient recycling. They decompose organic matter to release nutrients. They are also important to trap and transform nutrients into the soil, which can be taken up by plant roots. Nutrient cycling rate depends on various biotic, physical and chemical factors. Examples of a nutrient cycle: carbon cycle, nitrogen cycle, water cycle, oxygen cycle, etc.

2. Nitrogen Fixation: The symbiotic nitrogen-fixing bacteria invade the root hairs of host plants, where they multiply and stimulate formation of root nodules, enlargements of plant cells and bacteria in intimate association. Within the nodules the bacteria convert free nitrogen to ammonia, which the host plant utilizes for its development. Examples of this type of nitrogen- fixing bacteria include species of Azotobacter, Bacillus, Clostridium, and Klebsiella.

3. Disease Suppression: Certain soil microbes can protect plants from diseases by outcompeting harmful pathogens or by producing substances that inhibit their growth. This natural form of pest control reduces the need for chemical pesticides. One such form involves rhizobacteria in plant roots acting as BCAs against other bacteria that are pathogenic to the plant, known as bacterial-bacterial pathogen interactions.

4. Soil Structure: Fungi and bacteria produce sticky substances that bind soil particles together, improving soil structure. Good soil structure enhances water retention, root growth, and aeration, all of which are important for healthy plant development.

Microbes also play a direct role in promoting plant growth through various mechanisms:

1. Symbiotic Relationships: Mycorrhizal fungi form symbiotic relationships with plant roots. These fungi extend the root system, allowing plants to access more water and nutrients, particularly phosphorus. In return, the plants supply the fungi with carbohydrates produced through photosynthesis. Rhizobium is capable of fixing atmospheric nitrogen and supply them to leguminous plants such as pea, bean, soyabean, lentils, etc. These plants in-turn provide them with energy in the form of carbohydrates.

2. Plant Growth-Promoting Rhizobacteria (PGPR): These beneficial bacteria live in the rhizosphere, the narrow region around plant roots. PGPR can produce hormones that stimulate plant growth, enhance nutrient uptake, and protect plants from pathogens. The PGPR comprises the following bacterial species: Pseudomonas, Azospirillum, Azotobacter, Klebsiella, Enterobacter, Alcaligenes, Arthrobacter, Burkholderia, Bacillus, and Serratia, which enhance plant growth and yield production

3. Biocontrol Agents: Microbes act as biocontrol agents in three ways, either they cause diseases in the pests or compete with them or kill them. Biotechnology has extended widely and has developed many biocontrol agents. For example, Bacillus thuringiensis is a bacterium used as a biopesticide against certain insect pests.

Incorporating microbes into sustainable farming practices can lead to numerous benefits:

1. Reduced Chemical Use: Beneficial bacteria have the ability to decrease the demand for chemical pesticides and fertilizers by improving nutrient availability and inhibiting illness. This minimizes the negative effects of agriculture on the environment while also lowering production costs for farmers.

2. Improved Soil Health: Over time, soil health can be enhanced by the regular application of microbial inoculants, or products containing beneficial bacteria. Rich soil holds water better, resists erosion better, and is home to a wide variety of plant and animal species.

3. Increased Crop Yields: Healthier soil and plants often result in higher crop yields. By fostering a balanced microbial community, farmers can achieve more consistent and sustainable productivity. Microbial products can increase crop yields and have potential to complement or replace agricultural chemicals and fertilizers. Many companies have started to exploit individual microorganisms as biocontrol or bio fertilizer products and develop carrier‐based inoculants of beneficial strains

4. Climate Change Mitigation: Healthy soils with robust microbial activity can sequester more carbon, helping to mitigate climate change. Additionally, practices like reduced tillage, which preserve soil structure and microbial communities, further contribute to carbon sequestration. In Carbon Sequestration, certain bacteria and algae convert carbon dioxide into organic matter, which is then stored in the soil. This helps remove excess carbon dioxide from the atmosphere, mitigating the effects of global warming.

Farmers around the world are increasingly turning to microbial solutions to enhance sustainability. Here are a few examples:

1. Cover Crops and Crop Rotation: Planting cover crops and rotating different crops can enhance microbial diversity and activity in the soil. Cover crops like legumes can also fix nitrogen, enriching the soil for future crops.

2. Composting: Composting organic waste returns nutrients to the soil and fosters a rich microbial community. Applying compost to fields can improve soil health and fertility.

3. Bio fertilizers and Bio pesticides: Products containing beneficial microbes, such as bio fertilizers and bio pesticides, are becoming popular alternatives to chemical inputs. These products harness the power of microbes to support plant growth and protect against pests.

4. No-Till Farming: Reducing or eliminating tillage preserves soil structure and protects microbial habitats. No-till farming can improve soil health and reduce erosion and runoff.

There are difficulties in incorporating microorganisms into sustainable agriculture, despite all of the advantages. Making sure that introduced microorganisms may settle and flourish in the field environment is a significant problem. The success of microbial inoculants can be influenced by variables such soil type, climate, and preexisting microbial communities.
Furthermore, additional investigation is required to completely comprehend the intricate relationships that exist between microorganisms, plants, and their surroundings. Developments in genetics, biotechnology, and microbiology are opening doors for the creation of more focused and efficient microbial products.

Microbes are the unsung heroes of nature; they are essential to sustainable agriculture. Farmers may enhance crop yields, lessen their reliance on chemicals, promote soil health, and slow down global warming by utilizing the potential of helpful bacteria. The potential for microorganisms to revolutionize agriculture and contribute to a more sustainable future is growing as our understanding of microbial populations expands. Accepting these little allies may hold the key to feeding the world and preserving the environment for future generations.

Thisuri De Silva

2023/AM/03

References:
   • https://www.frontiersin.org/journals/soil-science/articles/10.3389/fsoil.2022.821589/full
   • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10303550/
   • https://www.researchgate.net/publication/259480950_Role_of_microbes_in_sustainable_Agriculture
   • https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9740990/
   • https://byjus.com/neet/nutrient- cycle/#:~:text=Soil%20microbes%20play%20an%20important,biotic%2C%20physical%20and%20chemic al%20factors.
   • https://www.nature.com/scitable/knowledge/library/biological-nitrogen-fixation- 23570419/#:~:text=Examples%20of%20this%20type%20of,other%20organisms%20or%20from%20deco mposition.
   • https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/plant-growth-promoting- rhizobacteria#:~:text=The%20PGPR%20comprises%20the%20following,Zhang%20et%20al.
   • https://www.sciencedirect.com/science/article/pii/S1018364723003555#:~:text=Microbial%20interacti ons%20in%20the%20plant’s,as%20bacterial%2Dbacterial%20pathogen%20interactions.

Image references

   • https://www.freepik.com/premium-vector/man-scientist-microbiology-researcher-with-microscope- microbiologist-study-various-bacteria_55874718.htm
   • https://www.slideshare.net/slideshow/microbiology-59272077/59272077
   • https://www.dreamstime.com/nitrogen-cycle-vector-illustration-labeled-n-biogeochemical-explanation- process-educational-diagram-denitrification-fixation-image178332444
   • https://www.sciencedirect.com/science/article/pii/S2468227620302301

If you think about all the plastic that you see every day, like the plastic bottle you drink water from, the food that is wrapped in plastic, and the pen in your hand; where do all these plastics end up? We hope that they get recycled into new plastic. But it is estimated that only 10% of plastic waste is recycled, 14% is incinerated, and the rest is dumped into landfills, ultimately entering the natural environment. It is predicted that 4.8–12.7 million tons of plastics enter the oceans annually. This amount is likely to increase by an order of magnitude within the next decade. Plastic waste represents a major portion of all marine debris. All this plastic is a serious problem for marine life. It gets eaten by animals like whales, fish, and seabirds. These animals can then develop major health issues. Other kinds of plastic debris can entangle or strangle sea life. Microplastics and nanoplastics, which emerge from plastic degradation, are known to enter the food chain with negative consequences for organisms.

The versatile properties of plastics make them attractive materials for numerous applications. A class of high molecular weight polymers is referred to as plastics in general. Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polystyrene (PS), and polyvinyl chloride (PVC) are the most widely utilized plastics, with PE and PP making up more than half of global output. The major drawback of plastic is that most of it doesn’t biodegrade. Plastics are believed to persist in the environment for centuries. For example, an empty jug of laundry detergent that enters the ocean will still be there for hundreds of years from now. Even the plastic engineered to be biodegradable takes a very long time to break down. Dealing with this needs some innovative thinking.
Scientists have discovered that microscopic marine microbes are eating away the plastic, causing trash to slowly break down. The degradation of plastics through biological processes is called bioremediation and is of great significance for ecological health. Therefore, the feasibility of plastic degradation by microorganisms has attracted a lot of attention. Bioremediation is a process in which microorganisms metabolize carbon sources in the form of organic matter. During this process, they do not produce toxic by-products and either provide energy to the microorganisms or transform the matter into other useful products.
The first step of microbial degradation of plastics is the microbial colonization on the plastic surface through adhesion, which is the prerequisite for enzymatic degradation. Hydrolysis is the second step which consists of the combination of enzyme and polymer matrix. The extracellular enzymes such as depolymerase and hydrolases cleave the polymer chain. The polymer chain after being attacked by enzymes results in small oligomers or monomers that bacteria can take into their cells. Otherwise, these small oligomers and monomers can be absorbed after their metabolism occurs outside the cell. Compared with oxidative degradation of large plastics or plastic fragments, enzymatic degradation can be measured by weight loss and the addition of functional groups. One of the biggest changes in MPs is the weight loss of plastics during biodegradation. This involves comparing the initial weight of the microplastics (MPs) with their weight after contact with microorganisms.

While some enzymes can break down PET efficiently, the ability to break down PE and PP is not well-documented and remains under significant research. A variety of enzymes such as cutinases, esterases, lipases, laccases, peroxidases and ureases from bacterial and fungal sources have been found to have the ability to break down PE, PET and PP. In fungi, the distribution and penetration ability of fungal hyphae are a significant factor in their original colonization before depolymerization and their enzyme capacities to enhance hyphal attachment to hydrophobic substrates. Fungal species with substantial plastic degrading properties include Fusarium solani, Alternaria solani, Aspergillus fumigatus, Spicaria sp., Geomyces pannorum, Phoma sp., Penicillum sp., etc. Some hydrolyzable plastics and PET are degraded by highly efficient bacteria, such as Ideonella sakaiensis 201-F. I. sakaiensis hydrolyzes PET into its monomers ethylene glycol (EG) and terephthalic acid (TPA). This process requires the synergistic action of two enzymes PETase and METase. Both these enzymes are potent as PET-degrading agents and have gained significant attention to reduce plastic waste. Scientists have designed in their latest research I. sakaiensis strain enzymes to improve degradation efficiency. The enzymes were genetically modified to work more efficiently than in their natural state. A refined and tuned PET hydrolase has shown great efficiency, producing at least 90% PET depolymerization into monomers within a 10-hour period.
Extreme environmental microorganisms, such as halophiles and psychrophiles, also exhibit plastic degradation potential. These special environments require the screening of more effective plastic-degrading bacteria. Plastic-contaminated places are characterized by extreme environmental conditions, such as low or elevated temperatures, acidic or alkaline pH, high salt concentrations, or high pressure. At elevated temperatures, several thermophiles have shown high potential for polymer degradation, similar to high-temperature plastic degradation agents. For example, it was reported the first time that Chelatococcus sp. E1 isolated from a compost sample was able to degrade PE when pretreated PE samples were set at 60°C.

Studies on the biodegradation of plastics can help to explain how microorganisms work and their potential to reduce the amount of plastic in the environment. They can also help to develop better enzymes to mitigate the issues related to plastic waste.

Sajini Irosha Devabandu

References
Cai, Z., Li, M., Zhu, Z., Wang, X., Huang, Y., Li, T., Gong, H., & Yan, M. (2023). Biological Degradation of Plastics and Microplastics: A Recent Perspective on Associated Mechanisms and Influencing Factors. Microorganisms, 11(7), 1661–1661.
‌ Zhai, X., Zhang, X.-H., & Yu, M. (2023). Microbial colonization and degradation of marine microplastics in the plastisphere: A review. Frontiers in Microbiology, 14, 1127308.

Image Courtesy
Featured Image: https://images.app.goo.gl/yX3Rva3JoExuaei76

Emergence and re-emergence of foodborne pathogens is a major concern of public health agencies and organizations, industries, and consumers. Factors that contribute to the emergence include, changes in the behavior of microorganisms and consumers, changes in agricultural methods and animal husbandry, increase of foreign travel, global food distribution channels, and climate change. Furthermore, advances in molecular technologies and pathogen detection methods enhance the recognition of the presence of new pathogens. Emerging foodborne pathogens are often zoonotic in origin and may include Gram-negative and Gram-positive bacteria, parasites, and viruses. Re-emergence of previously established foodborne pathogens after the acquisition of new virulence factors, including antibiotic resistance determinants may cause for the development of more virulent pathogens. In this article, various important emerging foodborne pathogens, such as Escherichia coli O157:H7, Shiga toxin-producing E. coli serogroups, pathogenic hybrid E. coli, extraintestinal pathogenic E. coli, drug-resistant foodborne bacteria, Clostridium, hepatitis E virus, and others, are discussed, along with the factors that may involve in their emergence. Reducing foodborne illnesses and the emergence and re-emergence of pathogens requires global partnerships among the government agencies, food industry, and other groups involved in food safety. The most important key terms are foodborne pathogen, emerging, re-emerging, zoonosis, virus, bacteria, parasite, antibiotic resistance.

The food supply chain is complex, with varying food compositions and changes in processing, distribution, consumption, microorganisms, and agricultural practices. This could lead in the emergence of new foodborne pathogens. In past 30 years, foodborne agents that had emerged includes bacteria, viruses, parasites, and biotoxins, and many were identified during outbreak investigations. An established foodborne pathogen may acquire greater pathogenic potential and re-emerge as a new pathogen. New foodborne pathogens emerge when unrecognized pathogens are identified and linked to foodborne transmission. Pathogens previously not associated with food transmission are identified as new foodborne pathogens when they are found to be transferred to humans through food. Many of these new foodborne pathogens arise from animal reservoirs and reach to human population through both animal and plant-derived foods.

An emerging pathogen has been defined as ‘‘the causative agent of an infectious disease whose incidence is increasing following its appearance in a new host population or whose incidence is increasing in an existing population as a result of long-term changes in its underlying epidemiology’’. Emerging infections are those in which the incidence in humans has increased within the past two decades or threatens to increase in the near future. There are many factors involved in emergence and re-emergence of foodborne pathogens which include human demographics, consumer attitudes, food processing and handling methods, pathogen behavior, and agricultural practices. Additionally, inadequate consumer education, insufficient public health services, societal factors, and the rise in multistate foodborne outbreaks also play significant roles. One of the major factors impacting food safety today is industrial food and animal production, particularly on larger farms, and increase of antibiotic-resistant bacteria

Antibiotics are used to prevent, control, and treat diseases in humans and animals. Additionally, it uses to growth promotion of food animals. However, feeding sub-therapeutic amounts of antibiotics to animals may lead to increase of drug resistance. Unfortunately, the most promising antimicrobial drugs is even compromised by the inherent ability of microorganisms to develop tolerance to their detrimental effects of the drug. Antibiotic resistance is a property of microorganisms that gives them the ability to inactivate or exclude a drug or confers upon them the ability to block the inhibitory or killing effect of the drug. Another unfortunate aspect is that lesser new antibiotics are being developed due to economic and regulatory constraints, and thus there are few new drugs to replace the old, less effective ones. Annually in the United States, 2 million individuals are infected with antibiotic-resistant bacteria leading to 23,000 deaths and estimated cost of antibiotic resistance to the U.S. economy is $55 billion.
Drug-resistant microorganisms enter the food chain because of their presence in food animals. Fecal excretion of drug-resistant organisms leads to eventual contamination of the environment. Thus, animal food products, fruits, and vegetables can be contaminated with resistant microorganisms. Another part of the problem is that antibiotic resistance is rampant in the developing world due to the availability of antibiotics without a prescription, and there could be a transfer of resistant microorganisms to developed countries.

Antimicrobial stewardship can be defined as the optimal selection, dosage, and duration of antibiotics to maximize therapeutic benefits while minimizing harm to patients and the community and reducing the impact on future resistance. The proper drug used in correct dosage for the relevant microorganism will aid in the prevention of resistance. The development of resistance to antimicrobial agents could be slowed down by eliminating unnecessary antibiotic use in humans and animals. Spread of drug resistance can be prevented by immunization, good personal hygiene, and safe food preparation. Tracking antimicrobial-resistant infections, resistant microorganisms, and risk factors for infection will allow the development of strategies that will aid in the prevention of infections and the spread of resistant microorganisms. Since antibiotic resistance is a result of evolution, the development of new antimicrobials will be necessary to combat current resistant microorganisms. Additionally, new diagnostic tests will need to be developed to monitor resistance to these new antibiotics. It has been reported that 80% of antibiotics in the United States are used in animal production, of which 70% are important in human medicine.
Emerging foodborne pathogens are organisms that are either newly identified or have recently become more virulent and widespread. These pathogens can be bacteria, viruses, or parasites that cause foodborne illnesses. Their emergence can be attributed to various factors, including changes in food production and distribution, environment and human behaviour.

1.    Campylobacter jejuni: Known for causing gastroenteritis, it has become a leading cause of foodborne illness due to its presence in poultry.
2.    Listeria monocytogenes: Often found in dairy products and ready-to-eat foods, it poses a severe risk to pregnant women, newborns, and immunocompromised individuals.
3.    Norovirus: The leading cause of foodborne illness globally, it is highly contagious and often linked to contaminated water and food.
4.    Hepatitis A and E: Transmitted through contaminated food and water, these viruses can cause severe liver infections.
5.    Shiga toxin-producing E. coli (STEC): Variants like E. coli O157:H7 can cause severe disease, including hemolytic uremic syndrome.

1.    Globalization and Food Trade
The globalization of the food supply chain has increased the risk of spreading pathogens. Contaminated food can now reach international markets, leading to widespread outbreaks.

2.    Changes in Food Production and Processing
Industrialization of food production has created environments where pathogens can thrive. Mass production and processing can lead to cross-contamination and the spread of pathogens over large quantities of food.
3.    Climate Change
Changing climatic conditions can influence the distribution and prevalence of foodborne pathogens. For example, warmer temperatures can increase the survival and growth rates of certain bacteria.

4.    Antibiotic Resistance
The overuse of antibiotics in agriculture and medicine has led to the emergence of antibiotic-resistant strains of foodborne pathogens. These resistant strains are more difficult to treat and control, posing significant public health challenges.

5.    Human Behavior and Demographics
Changes in dietary habits, such as the increased consumption of raw and minimally processed foods, can elevate the risk of foodborne illnesses. Additionally, an aging population with weakened immune systems is more susceptible to infections.

1.    Improved Surveillance and Detection
Enhanced surveillance systems are crucial for early detection and response to foodborne outbreaks. Molecular techniques, such as whole genome sequencing, enable more precise identification and tracking of pathogens.

2.    Stronger Regulatory Frameworks
Implementing and enforcing stringent food safety regulations can help prevent contamination and reduce the risk of foodborne illnesses. International cooperation and harmonization of standards are essential for managing food safety in a globalized market.

3.    Promoting Safe Food Handling Practices
Educating consumers and food handlers about safe food practices can reduce the risk of contamination. This includes proper cooking, refrigeration, and hygiene practices.
4.    Research and Innovation
Investing in research to understand emerging pathogens and develop new technologies for detection and control is critical. Innovations in food processing and packaging can also help mitigate the risks associated with foodborne pathogens.

5.    Addressing Antibiotic Resistance
Efforts to reduce antibiotic use in agriculture and promote the development of alternative treatments are essential to combat antibiotic-resistant foodborne pathogens.

The emergence of new foodborne pathogens is a complex and evolving challenge that requires a multifaceted approach. By understanding the factors contributing to their emergence and implementing effective mitigation strategies, we can reduce the risks and protect public health. Continuous vigilance, innovation, and international cooperation will be key in addressing this growing concern. As we move forward, it is crucial to prioritize food safety and ensure that our global food supply remains safe and resilient in the face of emerging threats.

R.A.Imal Sandaru Mihiraj

Reg No:2023/AM/10

References

1.    World Health Organization. (2021). “Foodborne diseases.” Retrieved from [WHO](https://www.who.int/news-room/fact-sheets/detail/foodborne-diseases).
2.    Centers for Disease Control and Prevention. (2021). “Emerging Infections.” Retrieved from [CDC](https://www.cdc.gov).
3.    Food and Agriculture Organization of the United Nations. (2021). “The impact of foodborne diseases on human health.” Retrieved from [FAO](https://www.fao.org).

4.    Abravanel, F, Lhomme, S, El Costa H, Schvartz B, Peron J-M, Kamar N, Izopet J. Rabbit hepatitis E virus infections in humans, France. Emerg Infect Dis 2017;23:1191–1193.

5.    Albert MJ, Faruque SM, Ansaruzzaman M, Islalm MM, Haider K, Alam K, Kabir I, Robins-
Browne R. Sharing of virulence-associated properties at the phenotypic and genetic levels between enteropathogenic Escherichia coli and Hafnia alvei. J Med Microbiol 1992;7:310–313.

6.    Alemayehu A. Review on emerging and re-emerging bacterial zoonotic diseases. Am Euras J Sci Res 2012;7:176–186. Andersson DI, Hughes D. Microbial effects of sublethal levels of antibiotic. Nat Rev Microbiol 2014;12:465–478. Anonymous. NARMS 2011 Retail Complete Annual Meat Report, Table 11. 2011a. Available at: www.fda.gov/downloads/ AnimalVeterinary/SafetyHealth/AntimicrobialResistance/NationalAntimicrobialResistanceMoni toringSystem/UCM 334834.pdf, accessed April 23, 2018.

7.    Cuny C, Friedrich A, Kozytgska S, Layer F, Nu¨bel U, Ohlsen K, Strommenger B, Walther B,
Wieler L, Witte W. Emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different animal species. Int J Med Microbiol 2010;300:109–117.
8.    Emerging and Re-Emerging Foodborne athogensJames L. Smith and Pina M. Fratamico
9.    https://www.centralstate.edu/news/foodborne-pathogens-six-questions-researcher

Gardening is more than just a hobby. It is a journey of nurturing and cultivating life within your own backyard. However, every gardener faces challenges with one of the most feared being plant infections. In this comprehensive guide, you will be able to explore the interesting subject of plant health, tracing the pathogenic root causes, early detection methods, effective prevention strategies, essential gardening tips, and highlighting the role of beneficial microorganisms in maintaining a flourishing garden.

Plant diseases come in various forms, each caused by different pathogens such as fungi, bacteria, viruses and nematodes. These tiny organisms can devastate your plants by causing symptoms ranging from leaf spots and wilting to fruit rot and stunted growth.

Effective plant disease management depends on early detection. Watch for symptoms and signs such as discoloured or spotted leaves, wilting even with enough watering, unusual growths or mold, and a sudden drop in the health of the plant. Early detection of these signs and symptoms enables immediate intervention to reduce damage.

The following elements influence a plant’s vulnerability to diseases:
•    Environmental factors: High humidity, an abundance of moisture, and inadequate air circulation provide the perfect environment for bacterial and fungal diseases to grow.
•    Soil Health: Plants can become weaker and more susceptible to disease due to factors such as compacted soil, nutritional deficits, and unbalanced soil pH.  
•    Cultural Practices: Plant overcrowding, poor watering methods (such as overhead watering) and insufficient spacing stunt plant development and raise the risk of disease.

Take into account these preventive steps to protect your garden from diseases:
•    Select plant varieties that are resistant to disease: Choose disease-resistant varieties. Suitable solutions for your region can be recommended by nearby nurseries and gardening centers.  
•    Practice Crop Rotation: Rotate your crops every year to break down disease cycles in the soil. Additionally, this method lowers insect populations and protects soil fertility.
•    Optimize Plant Spacing: Leave enough space between plants to enhance air circulation and lower surrounding humidity, both of which prevent the development of disease.  
•    Water Wisely: Water plants from the base up in the morning to minimize fungal growth by letting the leaves dry during the day. Avoid overwatering, as it will encourage root infections in the wet soil.  
•    Maintain Garden Hygiene: Keep your garden clean by getting rid of any sick plant material as soon as possible to stop infections from spreading throughout the garden. To avoid cross-contamination, clean gardening tools on a regular basis.

Use following tips to improve your gardening process:
•    Enhance Soil Health: To improve nutrient content and encourage advantageous microbial activity, supplement soil with organic matter such as old manure or compost.
•    Appropriate Planting Methods:  The right depth and spacing between seeds and seedlings are essential to obtaining maximum root development and overall vigour of the plant.
•    Benefits of Mulching: Cover plants with organic mulch (such as straw or crushed leaves) to control soil temperature, inhibit weed growth and preserve soil moisture.
•    Pruning Techniques: Prune plants frequently in order to get rid of unhealthy or dead sections, enhance ventilation, and stop diseases from spreading throughout the garden.
•    Integrated Pest Management (IPM): Use IPM techniques to manage pests without using chemical pesticides, such as attracting beneficial insects, utilizing natural predators, and engaging in companion planting.
•    Seasonal Alterations: Adapt gardening techniques to the various seasons. In hot conditions, provide plants shade, enough water and protection.
•    Companion Plants: To improve plant health and naturally ward off pests, consider companion planting. For instance, placing fragrant herbs like mint close to tomatoes can enhance flavour and keep pests like aphids away.

Microbes are essential to the health of the soil and the vitality of plants. Mycorrhizal fungi, for example, are beneficial microorganisms that develop symbiotic associations with plant roots to aid in nutrient uptake and increase plant resistance to disease. By competing with harmful pathogens, these beneficial bacteria establish a healthy and well-balanced garden ecology. 

Chilli Pepper Diseases: Chillies can cause several diseases, such as:
•    Anthracnose: This disease causes dark lesions on leaves and fruits, which reduces yield and causes fruit rot.
•    Powdery Mildew: White powdery spots on leaves that weaken plants by preventing photosynthesis.
•    Bacterial Leaf Spot: Water-soaked patches on leaves that spread quickly in humid environments.
Papaya Diseases: The following diseases can affect papaya plants:
•    Papaya Ring Spot Virus (PRSV): This virus causes deformed fruit, slowed growth, and mosaic patterns on leaves.
•    Anthracnose: Similar to those affecting chilli peppers, damaging leaves and fruits.
•    Fusarium Wilt: This disease causes the plant to wilt, yellow its leaves, and eventually die.
Thinking back on my personal gardening experience, I’ve faced a number of difficulties and picked up some important knowledge about controlling plant diseases. One event that stands out in my memory is a noticeable powdery mildew attack on my chilli pepper plants. When I first saw the white powdery patches covering the leaves and stems, I was scared for the health of my entire crop, and I searched for looked to organic solutions to save my plants. I sprayed the afflicted plants with a homemade solution of baking soda, water, and a few drops of dish soap, which I applied every few days. This easy mixture reduces the mildew. Furthermore, I made sure to water the plants at the base of them in the morning and trim the infected leaves to enhance air circulation. In addition to saving my chilli peppers, these preventive measures ensured the need for immediate and on-going care, particularly as my garden was in humid area where fungal diseases are common.
My papaya plants were afflicted with some virus diseases in another case. There were malformed fruits and different patterns on the leaves. I was worried that I could lose all of my papaya plants. I discovered the advantages of using virus-resistant papaya varieties after doing some research and getting information from the agricultural regional office. In order to stop the virus from spreading further, I also put in place a cleaning program that involved quickly removing and discarding contaminated plants.    
Another technique I used was that of making use of the application of wood ash to strengthen the soil and fight fungus-related illnesses. Ash is a natural amendment I have been putting in my garden. I sprinkle a thin coating of ash into the soil around the base of my plants. The ash’s alkaline properties contribute to the pH balance of the soil and supply vital nutrients like calcium and potassium which improve, plant health generally.
Utilizing ash not only increased the adaptability of plants but also improved the quality of the soil. This experience revealed many advantages of using natural garden modifications, especially in areas with high levels of humidity and regular rains.
You may establish a dynamic garden by learning about the origin of plant diseases, putting proactive preventive measures into place, and maintaining a healthy garden ecology. This will aid you in designing an environment that is durable and colourful. Accept these methods, keep learning, and take pleasure in the benefits of a year-round, healthy garden.  
Have you found diseases like Anthracnose in your chilli peppers or any type of disease in your papayas? How did you overcome these diseases effectively? Share your experience and tips in the comments below! Your tips could help fellow gardeners tackle similar challenges in their gardens.     

References:
1.    Wenke Greenhouses. (n.d.). Home. [online] Available at:
https://wenkegardencenter.com/ [Accessed 25 Jun. 2024].
2.    extension.okstate.edu. (2021). Non-Chemical Methods for Controlling Diseases in the Home Landscape and Garden – Oklahoma State University. [online] Available at: https://extension.okstate.edu/fact-sheets/non-chemical-methods-for-controllingdiseases-in-the-home-landscape-andgarden.html#:~:text=Sanitation%20%E2%80%93%20Plant%20pathogens%20are%2 0less [Accessed 25 Jun. 2024].
3.    joe gardener® | Organic Gardening Like a Pro. (2023). Microbe Science for  Gardeners | Soil Microbiology | joegardener®. [online] Available at: https://joegardener.com/podcast/microbe-science-gardeners-robert-pavlis/ [Accessed 25 Jun. 2024].
4.    Radhakrishnan, N. (n.d.). EFFECTIVE ORGANIC STRATEGIES FOR PLANT DISEASE MANAGEMENT. [online] Available at: https://greenaria.in/wpcontent/uploads/2024/02/EFFECTIVE-ORGANIC-STRATEGIES-FOR-PLANTDISEASE-MANAGEMENT.pdf [Accessed 25 Jun. 2024].

L.B.W. Anusari

The scientific revolution emphasizes a balanced diet with fresh fruits and vegetables (FFV) as essential sources of minerals, phytochemicals, and micronutrients. Since the 1980s, FFV demand has surged as people seek healthier diets, particularly in developed nations. The Food and Agriculture Organization (FAO) recommends that consuming 400g of FFV daily, helps to prevent chronic illnesses like diabetes, cancer, hypertension, obesity, and cardiovascular diseases. However, foodborne outbreaks associated with FFV are also increasing. Diarrhea, vomiting, and dehydration are the most common foodborne outbreaks associated with FFV caused by the presence of disease-causing microorganisms including Escherichia coli, Salmonella enterica, and Listeria monocytogenes. In Sri Lanka, leafy greens like lettuce and gotukola are commonly consumed as FFV. Although, these and other FFV are susceptible to contamination by pathogenic microbes throughout the growth, harvest, handling, processing, and distribution stages via insects, bird and rat feces, human excreta, polluted water, soil, fertilizer, containers, equipment etc. The country has seen a rise in gastroenteritis outbreaks linked to FFV consumption over the past 20 years. Despite the growing focus on foodborne illnesses from FFV, there’s a lack of clarity on contamination sources across the supply chain.

Farmers, food companies, consumers, researchers, and legislators are increasingly concerned about diseases from FFV. Thus, understanding microbial risk factors associated with FFV is critical, highlighting the need for prompt examination and identification of contaminants and their root causes.

FFV consumption in recent years is led by Asia, followed by Europe, North America, Oceania, and Africa. Europe’s consumption slightly surpassed North America’s, where a decline was noted. Africa and Asia have shown a steady increase in FFV consumption between 2001 and 2013. Along with that vegetable and fruit production rose significantly from 2000 to 2010 and over the past 18 years, respectively. In India, the urban population prefers fresh produce over fast food. However, the major producers (China and India) also face frequent contamination issues. In Sri Lanka, affordability and accessibility lead to higher consumption of vegetables like cabbages and tomatoes, necessitating research on microbial contamination.

The Fresh fruits and vegetables are characterized by high moisture and nutrient content, making them susceptible to contamination at any stage of production and processing. Contamination sources can be divided into preharvest and postharvest categories. Sources of preharvest contamination include human contact, applications of raw manure and compost, absorption from soil or groundwater, and exposure to contaminated water. Postharvest contamination can occur due to human handling, insects, and animals, by equipment used for harvesting and processing, across transportation methods, and rinsing water at the retailer stage (figure 2). The composition of FFV supports microbial growth, further it is encouraged by postharvest procedures like peeling and slicing which release secretions from the produce.

Microbial hazards can spread across the production chain due to the absence of heat processes and long distances between farms and processing units. In Sri Lanka, issues regarding food safety include bacterial infections, fungal infestations, pesticide residues, heavy metal contamination, and artificial ripening agents. Contaminations can occur at any point in the food chain, from growth and harvest to preparation, washing, transportation, and even in the consumer’s kitchen. Common pathogens in FFV include gram-positive and gram-negative bacteria, yeasts, fungi, and viruses.  Implementing effective prevention measures requires identification of contamination sources and disease-causing agents throughout the production and processing chain. The initial microflora consists of commonly Bacillus cereus, Campylobacter spp., Clostridium botulinum, Enterobacter, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Shigella spp., Pseudomonas spp., and Yersinia enterocolitica.

In the United States, foodborne illnesses (figure 2) account for approximately 76 million cases annually, and 14 million of them are caused by known infections, resulting in about 60,000 hospitalizations and 1,800 deaths. FFV have been implicated in 98% of illnesses and 80% of outbreaks involving leafy greens since 1999. Recent multi-state listeriosis outbreaks in December 2021 and February 2022, linked to prepackaged salads, led to 53 infections and three deaths (CDC, 2022). In Europe, Listeria monocytogenes is the predominant pathogen in both packed and unpacked vegetables. Key pathogens in fresh fruits and vegetables include L. monocytogenes, E. coli O157, Salmonella spp., and Yersinia enterocolitica.

Postharvest fungal contamination is also a significant contributor to this issue. Fungi can alter plant tissues, promoting harmful bacterial growth, reducing shelf life, and contaminating other fresh produce. Pathogenic fungal strains such as Aspergillus, Penicillium, and Alternaria can contaminate FFV from growth stages up to consumption. Other significant fungi include Alternaria which causes contamination in citrus under cold storage; Botrytis, which causes grey mould and leads to significant economic losses; and Fusarium, Geotrichum, and others involved in various postharvest diseases. These fungi can produce mycotoxins like ochratoxin, citrinin, ergot, patulin, and fusaria, which pose severe health risks to humans and animals.

Viruses also contribute to FFV contamination. Between 2004 and 2012, norovirus was the leading pathogen in FFV outbreaks in the United States of America (59%) and the EU (53%). In the USA, salads were primarily linked to outbreaks, while in the EU, berries were the main cause. Other viruses like rotavirus, adenovirus, and hepatitis A also contribute to the foodborne illnesses.

To combat these issues, new strategies are required to minimize the microbiological hazards and prevent outbreaks, ensuring the safety and quality of FFV.

The invention and application of antimicrobial edible coatings have significantly extended the shelf life of fresh-cut fruits and vegetables. The coatings consist of natural antimicrobial agents, including organic acids, fatty acid esters, polypeptides, plant essential oils, nitrites, and sulphites. Chitosan is a popular and cost-effective compound, known for its antibacterial properties. Multilayered antimicrobial alginate-based coatings containing trans- cinnamaldehyde and beta-cyclodextrin have shown notable effectiveness against psychrotrophics, coliforms, yeast, and mould in fresh-cut watermelon. Similar coatings for fresh-cut melons and cinnamon bark extract for fresh-cut apples have been successful in extending the shelf life by inhibiting microbial growth.

Essential oils from various spices and plants, such as rosehip, lemongrass, pine, sunflower, mint, and basil, show promise as natural preservatives. However, their strong flavors can alter the taste of produce. Green tea extract which is rich in antimicrobial catechins like epigallocatechin-3-gallate (EGCG), has proven beneficial for fresh-cut dragon fruit. Additionally, bio preservation using native microflora helps to prevent pathogen growth on freshly cut vegetables.

These approaches collectively aim to enhance the shelf life and microbiological quality of fresh- cut fruits and vegetables, providing a safer and more sustainable solution for consumers.

Microbes are ubiquitous in the environment and inevitably present on fresh fruits and vegetables. The increasing demand for fresh produce, driven by population growth and health trends, has led to a greater focus on food safety. Pathogenic microbes on fresh produce pose significant health risks, leading to foodborne illnesses. Identifying and mitigating contamination sources throughout the production and distribution chain is crucial for ensuring food safety. Implementing novel approaches like antimicrobial edible coatings can help to reduce microbial risks and extend the shelf life of fresh-cut fruits and vegetables, ensuring safer consumption globally.

Gayani Malwattage

2023/AM/09

Reference

Balali, G. I., Yar, D. D., Afua Dela, V. G., & Adjei-Kusi, P. (2020). Microbial contamination, an increasing threat to the consumption of fresh   fruits and vegetables in today’s world. International    journal    of    microbiology, 2020(1),    3029295.
https://doi.org/10.1155/2020/3029295

Callejón, R. M., Rodríguez-Naranjo, M. I., Ubeda, C., Hornedo-Ortega, R., Garcia-Parrilla,
M. C., & Troncoso, A. M. (2015). Reported foodborne outbreaks due to fresh produce in the United States and European Union: trends and causes. Foodborne pathogens and disease, 12(1), 32-38. https://doi.org/10.1089/fpd.2014.1821
CDC. (2022, February 1). Listeria outbreak linked to packaged salads produced by dole.

Korir, R. C., Parveen, S., Hashem, F., & Bowers, J. (2016). Microbiological quality of fresh produce obtained from retail stores on the Eastern Shore of Maryland, United States of America. Food microbiology, 56, 29-34. https://doi.org/10.1016/j. fm.2015.12.003
Qadri, O. S., Yousuf, B., & Srivastava, A. K. (2015). Fresh-cut fruits and vegetables: Critical factors influencing microbiology and novel approaches to prevent microbial risks—A review. Cogent    Food    &    Agriculture, 1(1),    1121606.
https://doi.org/10.1080/23311932.2015.1121606

Image courtesy

 https://www.arlingtonva.us/Government/Programs/Health/Foodborne-Illness

A farmer named Sarath lived in a small rural community surrounded by beautiful fields and hilly landscapes. Sarath was famous for his rich crop of peanuts and corn, which provided his family and neighbors with food, making him the village’s pride.
After an unusually warm and rainy summer, Sarath noticed something strange. His corn was covered with mold, and the normally bright yellow seeds were discolored by black spots. Sarath, being concerned, decided to pay a visit to Vindya, the local smart lady, renowned for her expertise in herbal remedies and plants.

Vindya paid close attention to Sarath as he talked about the mold on his crops. “Sarath, that might be more than just ordinary mold.” she said, her expression growing serious. “It sounds like it could be aflatoxin, a toxic substance produced by certain molds, including Aspergillus flavus and Aspergillus parasiticus. Just like the weather we’ve experienced this season, these molds prefer warm, humid environments.”
Vindya continued to talk as Sarath had never heard of aflatoxin before. “Crops like corn and peanuts can get poisoned by aflatoxins. They seriously endanger the health of both people and animals.”

“There is a condition called aflatoxicosis, which can result in severe liver damage, jaundice, stomach pain, vomiting, and even death,” Vindya went on. “That’s not all. Low-level aflatoxins may damage the immune system, promote malnutrition, and develop liver cancer over time, especially in children.” Sarath was concerned. It never occurred to him that the mold on his crops might be so harmful. “What can I do to protect my crops and my family?” he asked.

Vindya clarified that it was important to identify aflatoxins. “ELISA (Enzyme Linked Immunosorbent Assay), HPLC (High Performance Liquid Chromatography), and mass spectrometry are among the techniques that can detect and quantify aflatoxins in food. Regulations are in place in several nations to limit aflatoxin levels. For example, to ensure food safety, the United States Food and Drug Administration restricts aflatoxins to 20 parts per billion in the majority of foods.”
Sarath gave a thoughtful look. “So, if I understand correctly, even small amounts of aflatoxins can be dangerous, and we need to be very careful about detecting and controlling them.”
Vindya said, “Exactly, Also, it goes beyond testing. The key is prevention.”

Vindya stated how crucial prevention is. “Aflatoxin contamination risk can be decreased with the use of good farming methods. Rotate your crops to prevent the buildup of mold in the soil. Decide when to plant and harvest, in a way that it reduces the growth of mold. Make use of crop types that are resistant to mold growth.”
Sarath listened and carefully noticed Vindya’s words of instruction. He questioned, “What about after the harvest?”

Vindya further explained on post-harvest handling. “Proper drying and storage are important. Before storage, make sure your grains are completely dry. Limit your moisture content to 12–13%. Grains should be kept in cold, dry and well-ventilated areas. Again, airtight containers might be useful. Additionally, remember to carefully use fungicides as necessary.”
Regular testing and inspection were also suggested by Vindya. “Early detection of contamination can be improved by routine testing for aflatoxins. Never eat infected grains if you come upon them. To stop additional contamination, dispose them properly.”

Sarath left Vindya’s house with a good understanding of the silent killer hiding in his crops. He was determined to protect his family and his village. He started by implementing the preventive measures Vindya suggested. He rotated his crops, used resistant varieties, and ensured proper drying and storage of his grains. He also began regular inspections and testing for aflatoxins. Whenever he found contaminated grains, he disposed them safely, preventing them from entering the food supply.
Sarath didn’t stop there. He knew that keeping his crops safe wasn’t enough. He wanted to share his knowledge with other farmers in the village. So, he organized a meeting at the Govijana center and invited Vindya to speak.

Vindya stood before the assembled farmers and began her presentation. “We are gathered here today to talk about a serious issue that affects us all, aflatoxins. These are toxic chemicals produced by molds that can contaminate our crops and harm our health, but with the right knowledge and practices, we can protect ourselves and our community.”
She then explained the science behind aflatoxins, how they are produced by molds, and the conditions that favor their growth. She talked about the health risks in simple terms, making sure everyone understood the seriousness of the issue.
“Imagine a small amount of poison,” Vindya said, “just a tiny bit in your food every day. Over time, it builds up in your body and can cause severe health problems. That’s what aflatoxins do. They are a silent killer.”

Following Vindya’s talk, the village’s farmers decided to act as a group. In order to pool resources and exchange information on avoiding aflatoxin exposure, they established a co-operative. They combined their funds to establish a small lab for regular checks and purchase testing kits.

Better storage facilities were also purchased by the co-operative. To keep the grains dry and free of mold, they constructed a large, well-ventilated grain storage facility with temperature and humidity controls. They employed a qualified technician to oversee the storage facility and conduct routine checks.

Sarath gained prominence within the co-operative. He assisted other farmers in putting good farming practices into effect by drawing on his experience and the information he acquired from Vindya. He arranged workshops on using resistant crop types, planting and harvesting schedules, and crop rotation.
Likewise, he set an example for other farmers by demonstrating the correct way to dry and store wheat. He gave a demonstration of how to use airtight containers and highlighted the need to maintain a clean, well-ventilated storage environment.
Sarath’s farm became a model for others to follow. His family and neighbors felt safer knowing that their food was protected from this silent killer, since his crops were healthy and free of aflatoxins.
There were challenges along the way. The weather wasn’t always friendly, which made it challenging to keep the grains dry. Budgetary constraints also existed since a large number of village’s farmers were having difficulty making ends meet. Still, the co-operative held on. They approached agricultural groups for assistance and requested funds from the government. They were given training, equipment, and financial support, all of which helped them maintain and upgrade their storage facilities and procedures.
The results of their work were visible in due course. Aflatoxin exposure has decreased in the village. The community’s health improved, and the number of diseases caused by aflatoxin exposure decreased. The farmers’ incomes increased as a result of their larger harvests and higher market prices. Mutual assistance and a sense of community were also promoted by the co-operative. Farmers collaborated to solve challenges, shared knowledge, and learned from one another. The town gained popularity as a role model, drawing tourists and academics interested to take note of their successes.

After an extremely wet season, Sarath saw the clear indications of mold on his corn once again. The abnormally moist conditions had made the ideal conditions for aflatoxins to grow, despite their best efforts. Sarath notified the co-operative of the problem right away.
The co-operative immediately got to work. To make sure that any stained grains were identified and removed right away, they stepped up their testing and inspections. They increased airflow in their storage facilities and added more drying processes.
Vindya continued to be an essential part of the community’s defense against aflatoxins. She updated the farmers on the most recent findings and advancements in the fight against aflatoxin. She also gave them an introduction to innovative tools and techniques for identifying and managing aflatoxins. The use of biological controls was one such technique. Vindya described how aflatoxins may be broken down by specific helpful microorganisms allowing the grains to be safely consumed. The cooperative decided to fund the new strategy, in order to improve defenses against the silent killer.

Sarath and the other farmers came to a mutual understanding on how important it is to teach the future generation. They began going to the neighborhood school to instruct kids on food safety and farming methods. Aflatoxin threats were discussed, along with the steps they were taking to ensure the safety of their food. The kids even helped their family farms and were keen to learn. They ensured that the teachings of aflatoxin avoidance were handed down through the generations by passing the knowledge they learned to their parents.
Everyone was aware of Sarath’s village’s success. News of their successful aflatoxin prevention program spread to the cities and villages nearby. Farmers from other regions visited them to learn and apply the same techniques at home. Authorities from the government and specialists in agriculture saw the progress of the community. They asked Sarath and Vindya to share their knowledge and experiences with a larger audience by giving speeches at conferences and seminars. Many people were motivated to take action against aflatoxins by their story, which increased food safety in the area.
Sarath’s community became stronger throughout the years. The co-operative developed as a result of their combined efforts. The village was well-known for its crop production as well as its dedication to public health and food safety.
With time, Sarath’s children took over the farm and carried on the traditions he had established. They increased the co-operative’s reach and assisted other villagers’ farmers in implementing similar practices. Many people’s food safety was enhanced owing to the village’s combined efforts, Sarath, Vindya, and the work they carried on.
An important lesson about the silent killer in grains can be learned from the story of Sarath and his people. Even though aflatoxins create serious health threats, their effects can be minimized with the right information and actions. We may improve our ability to protect ourselves and our food by being knowledgeable of the origins, risks to health, and techniques for detecting and controlling aflatoxins. To ensure food safety, it is important for everyone involved in the food industry including the consumers to be knowledgeable and cautious. Keep in mind that through raising awareness and taking proactive steps, we can ensure a secure food supply for everyone.

K.T. Hettiarachchi

References
•    World     Health     Organization     (WHO)     –     Aflatoxins:     https://www.who.int/news-room/factsheets/detail/aflatoxins
•    U.S. Food and Drug Administration (FDA) – Aflatoxins: https://www.fda.gov/food/foodbornepathogens/aflatoxins
•    Food and Agriculture Organization (FAO) – Aflatoxins: http://www.fao.org/food/food-safetyquality/a-z-index/aflatoxins/en/
•    Aflatoxin Toxicity – https://www.ncbi.nlm.nih.gov/books/NBK557781/
•    https://www.sciencedirect.com/topics/pharmacology-toxicology-and-pharmaceuticalscience/aflatoxin
•    https://www.mdpi.com/2072-6651/15/4/246
•    https://www.ncbi.nlm.nih.gov/books/NBK557781/#:~:text=Aflatoxin%20toxicity%20may%20result% 20in,%2C%20cirrhosis%2C%20and%20hepatocellular%20carcinoma.