Dr. Banarsi Lal
Earthworms are also known as farmer’s friends, intestines of the earth, ploughmen of the field, biological indicators and ecological engineers. They are commonly found in the soil and act as the soil conditioners. They are hermaphrodites and develop slowly except leaf litter dwellers. They have the capability to maintain the soil fertility and thus play a crucial role in sustainability in agriculture. They are considered as one of the most important soil animals. They play an important role in the management of biodiversity and ecosystem. Importance of earthworm in the ecosystem was documented very early by Aristotle, the Greek philosopher who called them “intestines of the earth” and then in 1881 Charles Darwin highlighted their role in breakdown of dead plant as well as animal matter. They can live for 2-8 years and can produce 8-12 cocoons per year. Worldwide there are about 3000 species of earthworms. Generally the species of earthworms used for preparation of vermicompost are Eisenia fetida and Eudrilus eugeniae. Along with the earthworms ,bacteria, fungi and actinomycetes also participate in decomposition. During hot summers they move to deeper layers and activates. They bring the nutrients from the deeper layers of soil and deposit them on the surface of the soil surface as the castings. Plant growth regulator like Auxin is produced in the castings of earthworm that stimulates the roots to grow more rapidly and much deeper. Nitrogen casting is higher in worm casts due to the occurrence of nitrogen-fixing bacteria in the earthworm gut as well as in worm casts. Earthworms normally require sufficient moisture for the appropriate growth and development.75-90 per cent of body weight of earthworms is constituted with the water. The increase of temperature above the critical point may be fatal for the earthworms. The country now has enough food grains but there is need to stress on the quality of the food for the mankind. Vermicomposting is the technology that synergizes microbial degradation with earthworm’s activity for reducing, reusing and recycling waste materials in a shorter span of time. Mutual action of earthworms and microbes brings faster decomposition as earthworms aerate condition, fragment and enhance surface area of the organic matter for microbial action. Vermicomposting is a very simple technology practiced by the farmer himself and some farmers make it as an enterprise. Vermicompost plays an important role in organic farming and can be made easily by using the locally available material at farmers’ field. Earthworms promote the growth and propagation of beneficial organisms in the soil.
Sustainable agriculture means the production of food from plants or animals using different agricultural techniques that protect the environment, society and animals. Although the excessive use of agro-chemicals increases the crop yields but it deteriorates the soil, environment and human health. The new agricultural practices have caused a fall in the biodiversity and disturbed the ecosystems. The product obtained by the modulation of organic waste in the earthworm gut is quite different from its parent waste material and is also known as black gold or vermicast. Climate change, land use pattern and nitrogen enrichment have also been reported to cause a change in soil biodiversity. Indian earthworms are dominant by indigenous species that contribute approximately 89% of total earthworm diversity and are represented by nine families, 67-69 genera, and 418-509 species. Out of them about 51 are exotic species. Earthworms play a crucial role in sustainable agriculture. With green revolution there was boost in agricultural production but it caused some adverse affect on the soil, environment and human health. Green revolution has resulted in boosting the production due to intensive agriculture. There was excessive use of chemical fertilizers and irrigation. In order to develop the healthy environment, soil and human health natural farming or organic farming is need of the hour. It is economically productive and simple with more profits and long lasting.
Earthworm burrows act as a channel for as pathways for plants root elongation, plant growth and especially in compacted zones typically found in deeper soil layers. Earthworms make the soil porous, increase the water infiltration rate and reducing soil erosion. It has been observed in some studies that earthworms release certain metabolites such as vitamin B and vitamin D into the soil which are good for the growth of plants. It has also been reported that earthworms can convert barren land into fertile land and increase agriculture output.Vermicompost and Vermiwash produced from various organic materials play an important role in eco-friendly farming, nutrient availability, pests’ protection and soil fertility improvement. The vermicast acts as buffer; it has a significantly lower volatile solid content and high nitrogen, phosphorus and potassium. With the use of vermiculture, cost of cultivation is reduced and quality of food is increased. The organic food is more costlier than the conventional food and thus one can generate more money by growing the organic food. It is a ‘win-win’ situation for both producers and the consumers. The cost of production of Vermicompost is lesser than the chemical fertilizers. The former is produced from ‘animal waste’-a raw material which is available easily at farmers’ field and the latter is obtained from ‘petroleum products’ which is a vanishing resource on the Earth. Vermicompost can be produced easily with the simple method while the chemical fertilizers are high-tech and high-cost products manufactured in factories. Vermicompost shortens the harvesting time and farmers can grow more crops every year. Earthworms are considered as the ‘nature’s gift’ in farm production. There is need to adopt the agricultural production system which should have high productivity and stability in yield. It should consume minimum water and can sustain even in dry spells. It should preserve water, air, soil quality and crop diversity. It should be a source of good health for all. It should save the energy. Earthworms maintain aerobic condition of soil. It also degrades the contaminants in the soil.Vermicomposting technology promotes agricultural sustainability. Earthworms facilitate the microbial and biochemical soil activity on the substrate. They also reduce the environmental risk. Earthworms and their vermicast work as a driving force in sustainable food production as they improve soil fertility, improve nutrition quality in food crops, protect crops from various diseases and pests and diseases and increase plants growth parameters. They are the cheapest source for the production of quality food for the mankind. There is need to utilize the earthworms for the management of agro-ecosystem.
(The writer is Chief Scientist & Head, KVK Reasi, Sher-e-Kashmir University of Agricultural Sciences &Technology-Jammu (SKUAST-J)
