Under present day condition, it becomes very essential to protect environment from further degradation, develop appropriate technologies for use in recycling various organic waste and to harness energy thus minimizing environmental stress. Vermitechnology is a promising technique that has shown its potential in certain challenging areas like augmentation of food production, waste recycling, management of solid wastes etc (Tripathi et al., 2005). The word Vermiculture biotechnology implies a modern technique of harnessing the ecosystem for effective utilization of the organic waste with the help of earthworms, which results into generation of useful organic manure. It helps to avoid the environmental pollution and expenditure of resources to treat the organic waste (Singh, 2004). A large volume of organic matter generated from agriculture activities, dairy farm, industrial establishments, animal shelters and household activities are dumped to putrefy without proper utilization. Wastes are the misplaced valuable resources, which can be utilized by proper composting. The composted waste, the vermicast which has higher qualities of manure can be used to feed our “Nutrient-organic matter-hungry” soils (Ismail et al., 2003). Vermicompost is considered superior to other types of compost because of its quality. Soils with vermicasts have roughly 100 times more bacteria than soil without worms. Moreover plant growth promoting substances have been reported to be present in vermicasts.
The increase in human population and urbanization has led to food scarcity. To increase food production agriculturalists are tempted to use more amounts of chemical fertilizers and pesticides frequently, which cause several hazards to soil microflora, which in turn affects fertility. For instance chemical fertilizers like Ammonium sulphate, Ammonium chloride and Urea reduce the soil pH. Chlorides are highly toxic to most of the crop plants. The accumulation of chemicals by biomagnification in plants and their products causes several diseases in human beings. Infant disease such as methanoglobinaemia is caused due to nitrogen containing fertilizers. The residues of chemical fertilizer cause concern over the safety of food and sustainable production. Hence, it becomes imperative for the researchers and planners to develop an alternative viable strategy to counteract the problem.
Organic farming, usage of eco-friendly manures such as green manures, urban waste, rural wastes, etc. can bring sustainability to agriculture. Vermicomposting is an eco-friendly, economical, efficient novel technology that can be applied to utilize agricultural and other organic wastes. This technology also provides opportunities for self-employment for rural people, by utilizing the available agricultural resources. The technology had begun in Ontario, Canada in 1970 and now is practised in countries such as USA, Japan and Phillipines. In India, vermicomposting technology is getting familiarized in this decade. A number of agro-industrial organic wastes discarded as unusable, which contain essential nutrients can be exploited to improve the physical, chemical and biological properties of soil. The digested product of earthworm known as castings, which is rich in nutrients such as phosphorous, potassium, calcium and magnesium increases the soil fertility.
Potential environmental benefits of Vermitechnology include: reduction of noxious qualities of organic wastes, elimination/reduction of harmful micro organisms; conversion of agro-wastes into high value fertilizer and production of food and feed from food discards (Tripathi et al., 2005). Vermicompost envisages the soil fertility for years together with out affecting the food quality. The NPK content of vermicompost is higher than the farmyard wastes (FYW).
| Nutrients | Vermicompost | Farm yard wastes (FYW) |
| Nitrogen (N) | 0.5 % | 0.18 % |
| Phosphorous (P) | 0.57 % | 0.2 % |
| Potassium (K) | 3.14 % | 0.5 % |
Sujatha et al. (2003) reported earthworm castings in the home garden often contains 5 to 11 times more Nitrogen, Phosphorous and Potassium than the surrounding soil. Castings of earthworm also contain abundant sources vitamins, antibiotics and enzymes such as proteases, amylases, lipases, cellulases and chitinases. Vermicompost technology can provide employment to millions of youth, can eliminate dependence on chemicals; can convert wastes into fertilizer; can bring waste land under cultivation, can feed hungry citizen and can make a country green and prosperous in a span of just a few years (Shewta et al., 2004). This technique also helps to conserve the biodiversity, which is the need of the hour. Apart from providing self-employment opportunities for the weaker section and profitable agricultural waste utilization it will also help in maintaining the environmental/ecological balance.
Most towns and cities in India do not have proper waste management systems and untreated solid waste is generally dumped in landfills or on the roadsides and the liquid wastes are discharged into water bodies. Domestic wastes are mostly organic and on average are about 50% of the total wastes. It is estimated that each household produces not less than 200 kg of organic solid wastes per year. This can be put to productive use rather than being thrown into the bin from where it makes its way to over loaded landfills. These wastes can be considered as a resource to produce manure for the soil using vermicomposting technology.
Large quantity of potential agro-industrial wastes and byproducts are thrown out as wastes/under utilized by the local population since they are not aware of its importance. The materials can be utilized profitably by vermicomposting, which is a low cost technology. Unemployed rural population can do this, as part time/ full time profession if they are aware of the technical know how to utilize the materials. Awareness about Vermiculture and vermicomposting will motivate the rural people to start Vermicomposting units, which can fetch regular income.
Vermitechnology is popular because it is a simple methodology with low investment and does not need sophisticated infrastructure. To process one ton of organic matter daily, it would require about 1500 sq meters of space with 6 workers. It would produce about 70 tons of earthworm casting annually (Gupta, 2003). Innovative, interested and talented rural people can be successful entrepreneurs in vermicompost production and accruing profits will enhance their life style and income. They will be able to spend time usefully by getting job opportunities with the help of self-employment schemes.
Earthworms constitute more than 80 percent of soil invertebrate biomass. They feed on a variety of organic waste materials and produce “Vermicastings”. It contains more microorganisms, organic matter and inorganic minerals in the form that can be used by plants. Nearly 10-15 percent primary production is channelized through earthworms. In absolutely ideal conditions of comfort and ground up, moist food, the herd will recycle their own weight in wastes every 24 hours (Gupta, 2003). Vermicomposting is an ideal and appropriate method for disposal of nontoxic solid and liquid organic wastes.
There are about 3000 species of earthworms in the world. At present, earthworm fauna in the Indian subcontinent comprises 509 species placed in 67 genera and 10 families. Earthworms in ecological terms are classified into three groups depending on their ability to make burrows and the intricacy of burrows:
Epigeic earthworm species efficiently enhances the rate of organic manure production through biodegradation/mineralization compared to other species. The ideal epigeic category of earthworm used for Vermicomposting are: Eudrillus eugeniae, Eisenia foetidae, Perionyx excavatus, Lampito mauritii and Dravida willsil
Epigeic earthworms remain active throughout the year under favourable conditions. Moisture levels, temperature, food and space are essential for their survival and biomass production. Temperature below 35°C and moisture level between 40 and 60 percent is ideal condition for earthworm activity.
The convenient dimension such as 2m x 1m x 1 m has to be prepared.
Though earthworms can digest a diverse range of organic residues and yield rich vermicompost, it is better to use pre-digested organic wastes for worms to act faster and produce high quality compost. The pre-digested waste is an ideal medium for the worms to act on. The pre-digested material will be converted into quality vermi-compost with in 30 days. The composite organic wastes should be degraded using diluted fresh cow dung slurry, which is to be sprinkled over the several layers of the heap. The heap has to be kept moist by regular irrigation, and it will have to be turned two to three times at an interval of ten days.
| 5th Layer | 5 cm | Wet cow dung |
| 4th Layer | 25 cm | Agriculture wastes, farm waste, animal droppings |
| 3rd Layer | 30 cm | Agriculture wastes, farm waste, animal droppings (application of earthworm over this bed) |
| 2nd Layer | 5 cm | Coarse sand |
| 1st Layer | 10 cm | Broken bricks / pebbles |
Earthworms can be collected from the fields by applying a simple technology. In a well-shaded patch of the land where the earthworm castings are found, a small area of 1 m x 1 m should be embarked. About 500 g jaggery and an equal quantity of fresh cow dung should be mixed in 15 to 20 l of water and this diluted slurry should be sprinkled over the area. Wet pats of cow dung is scattered over the area and a layer of moistened rice straw should be laid over it. The whole area is covered with a jute sack. Regular watering should continue for a period of 20-25 days and care should be taken to avoid water stagnation. When the cover is removed one can see 600-700 small worms that can be used for composting.
The optimum number of worms to be introduced is 100/m length of the bed. Raw materials will be spread again over the earthworms gently up to the level of 25 cm. In continuation, wet cow dung with moisture will be covered over the level of 5 cm. Leaf dust of neem, Acorus calamus rhizome dust and neem cake can be used in the management of enemies. After a period of 10 days the organic layering is mixed well gently without injuring the earthworm.
Earthworm’s gut is an effective tubular bioreactor with raw materials (feed) entering from one end and the product (castings) coming out through the other end. The temperature is maintained by a novel temperature regulatory mechanism, accelerating the rates of bioprocess and preventing enzyme inactivation caused by high temperature. Gizzard is colloidal mill in which the feed is ground into particles smaller than 2m, giving thereby, an increased surface area for microbial processing. Earthworm gut has nearly 73 percent of gram-ve, facultative anerobic, Vibrio sp (an autochthonous micro flora) that are responsible for the degradation of ingested food. Mucous produced by the glands in the anterior region of the earthworm gut provides a favorable substrate for symbiotic microorganisms that decompose complex organic compounds.
Watering has to be stopped 7 days prior to harvest so that worms settle at the bottom layer. The layer will be obtained as black color. It is the indication that the conversion of the raw materials and castings into compost. Matured compost, a fine loose granular mass will be removed from pit, sieved, dried for 12 hours in shade and packed in fertilizer bags for storage. This matured compost has rich nutrient value.
The worms and its cocoon are to be collected by sieving and used for subsequent Vermicomposting.
Vermiculture and vermicomposting technology is easy to practice, ecologically safe, economically sound and can create more employment opportunities for the rural people to upgrade their standard of living. At present Vermiculture technology is all set to emerge as a big business of the next century. The organic manure obtained from different waste materials using this versatile technique will avoid pollution problems to a greater extent. India being agriculture based country, it could easily produce millions of tones of Vermicompost, and considerably reduce the use of chemical fertilizers.
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