The Role of Microbial Preparations in Agriculture
Improving Soil Quality: Microbial preparations help maintain and improve soil structure, enhancing the natural fertility of the soil. The microorganisms in these preparations can break down complex organic materials into simpler nutrients that plants can easily absorb. This not only continuously provides nutrients to crops but also helps regenerate the humus layer in the soil, increasing water retention and reducing erosion.
Increasing Crop Yield and Quality: Microorganisms have the ability to fix nitrogen, dissolve insoluble phosphorus, and produce natural growth-promoting substances like indole-3-acetic acid (IAA). These substances help crops grow stronger, enhance their resistance to pests and harsh environmental conditions, thus increasing agricultural product yield and quality.
Reducing Chemical Fertilizer and Pesticide Use: Microbial preparations help reduce dependence on chemical fertilizers and pesticides by providing necessary nutrients for crops and naturally controlling pests. Reducing the use of these chemicals not only saves costs for farmers but also minimizes environmental pollution and ensures food safety.
Enhancing Biodiversity: Microorganisms play a vital role in maintaining biodiversity in the soil ecosystem. This diversity creates a balanced environment where different microbial species perform various ecological functions, thus maintaining the stability and sustainability of agricultural ecosystems.
Supporting Organic Farming: In organic agriculture, the use of microbial preparations is a key factor. These preparations not only provide nutrition for crops but also help control pests and weeds naturally. This is completely in line with the principles of organic farming, which prohibits the use of synthetic chemicals.
Contributing to Greenhouse Gas Emission Reduction: Microbial preparations, especially nitrogen-fixing microorganisms, help reduce greenhouse gas emissions such as nitrous oxide (N₂O) from agricultural soils. This emission reduction contributes to mitigating climate change, one of the essential goals of sustainable agriculture.
Therefore, microbial preparations are an essential solution in the effort to develop sustainable agriculture, improving both crop yield and quality while protecting the environment, maintaining biodiversity, and supporting organic farming methods. The combination of using microbial preparations with other agricultural practices will create a sustainable, environmentally friendly agricultural system that ensures food security in the future.
2. Types of Microbial Preparations That Have Been Researched and Developed
Research centers have developed various commercial products for agricultural production, such as BIMA (containing Trichoderma spp. strains) used for composting, BIONEMA (containing Purpureocillium spp. strains) for nematode control, and BIMIX (containing Bacillus sp., Streptomyces sp., etc.) for treating foul odors in livestock facilities.ư
Insect Pest Control Preparations
During their growth and development, crops are often attacked by insects, causing damage to yield and quality. Insects can harm crops at any stage, making control difficult. Chemical pesticides can only temporarily suppress outbreaks and are easily resisted. In agricultural environments, natural enemies exist to reduce insect populations, but relying solely on natural enemies cannot ensure timely pest control. By utilizing biological antagonism, researchers have identified microorganisms that can infect insects to develop high-density preparations for preventive applications from the outset, creating better control advantages.
The fungus Metarhizium anisopliae, commonly known as green mold, can secrete many extracellular enzymes such as protease, lipase, chitinase, and various toxins. This fungus has been recognized by many researchers worldwide for its ability to parasitize and control insects at both larval and adult stages. In 2014, the center studied and collected strains of M. anisopliae and completed the production process for the BIOMETAR preparation containing M. anisopliae, which can be applied to control aphids, mealybugs, caterpillars of scale insects, sweet potato weevils, and more. Other microbial preparations researched and applied include:
- Purpureocillium sp., Nomuraea rileyi, Bacillus thuringiensis (Bt), Lecanicillium tenuipes:
- Purpureocillium sp.: A fungus that secretes extracellular enzymes to degrade the eggshells and cuticles of nematodes. Additionally, it forms adhesive disks around the eggs, with some hyphae developing along the surface, creating a network of mycelium surrounding the eggs and female nematodes. This fungus can also parasitize mealybugs harming vegetables and fruit trees.
- Nomuraea rileyi: Capable of parasitizing important pests such as the soybean looper, diamondback moth, and other caterpillar species.
- Bacillus thuringiensis: Produces crystal toxins that are specifically toxic to certain insects.
- Lecanicillium tenuipes: A fungus that naturally parasitizes and kills various insects such as aphids, whiteflies, moths, beetles, and butterflies. The infection process involves mechanical penetration and enzyme secretion to directly enter the insect’s skin, introducing the fungus’s toxins into the host. The fungus then grows and invades the host’s tissues, quickly leading to insect death.
Plant Disease Control Preparations
In addition to insect pests, crops are severely affected by pathogenic fungi and bacteria. Common harmful fungi such as Collectotrichum sp., Phytophthora sp., Rhizoctonia sp., and Fusarium sp. persist in the soil and plant debris, making them challenging to manage. Understanding the characteristics of these pathogens and their antagonistic agents is a pathway for effective control. Microbial strains capable of controlling pathogenic fungi include Trichoderma spp., Bacillus spp., Pseudomonas spp., and Streptomyces spp., which have been researched and developed into preparations for use by individuals and organizations.
- Trichoderma spp., Bacillus spp., Pseudomonas spp., Streptomyces spp.: Effective against various soil-borne fungi and bacteria causing diseases such as damping-off, root rot, wilt, and more through antagonistic and parasitic mechanisms, as well as enzyme secretion. Additionally, they release growth-promoting substances through nutrient absorption or the secretion of metabolites that stimulate plant growth, such as growth hormones. One of the advantages of beneficial biological agents is their ability to persist in nature, creating a favorable environment that limits the excessive growth of pests.
Microbial Preparations for Soil Quality Improvement
The overuse of pesticides, inorganic fertilizers, and growth regulators in agricultural practices has led to soil degradation and infertility, making it difficult for plants to absorb nutrients. Therefore, alongside researching proper fertilization techniques, soil improvement must be conducted concurrently to promote green and sustainable agriculture. In recent years, modern biotechnology has significantly contributed to creating soil improvement products (providing organic matter to soil, helping the soil become loose and well-drained, preventing flooding), restoring degraded soil caused by prolonged chemical use, and enhancing beneficial soil microorganisms. Microorganisms also help convert organic matter in the soil into energy sources for plants, break down pesticides and pollutants, and facilitate the transport of minerals in the root zone. Thus, beneficial microbial preparations help increase crop yield and quality.The trend of using microbial preparations that rely on nutrient breakdown and synthesis to provide crops while protecting soil environments and reducing production costs, thus increasing farmers’ income, is gaining interest and application. The biotechnology center has researched and developed production processes for many microbial strains capable of solubilizing phosphorus, fixing nitrogen, and decomposing organic compounds into useful substances for crops. From these combinations of microbial strains, various product lines have been created, such as BIO preparations that fix nitrogen and dissolve insoluble phosphorus into soluble phosphorus, as well as products for decomposing fish, cow manure, and organic fertilizers.
Đăng ngày: 24/09/2024