Transcript of "Vermiculture and Vermicomposting Biotechnology for Organic Farming and Rural Economic Development"
Vermiculture and Vermicomposting Biotechnology for
Organic Farming and Rural Economic Development
By P. Rajendran¹, E. Jayakumar¹, Sripathi Kandula² and P. Gunasekaran² ¨ ³
Department of Zoology, Vivekananda College, Tiruvedakam, West
Sholavandan, Madurai 625 217, Tamil Nadu, India
Centre for Advanced Studies In Functional Genomics, School of Biological
Sciences, Madurai Kamaraj University (MKU), Madurai 625 021, Tamil
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.
Vermicompost for Organic Farming - an Eco-Friendly Approach
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.
Advantages of Vermicompost
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).
Farm yard wastes
Nitrogen (N) 0.5 % 0.18 %
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.
Vermicomposting for Indian Conditions
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.
Vermicomposting for Rural Development
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
Revenue Generation through Vermiculture and Vermicomposting
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.
i) Earthworm for composting
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.
ii) Selection of worms
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 earthworms that cannot make burrows in the soil strata. They can only move
through the crevices of the surface
Endogeic are the subsoil dwellers found in deeper region of the soil and
Anecic earthworms found in the soil, which are not frequently disturbed.
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
iii) Culture maintenance
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
iv) Space for earthworm culture and size of pit
The convenient dimension such as 2m x 1m x 1 m has to be prepared.
v) Raw materials for Vermicomposting
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.
vi) Preparation of vermibed
Layer 5 cm Wet cow dung
Layer 25 cm Agriculture wastes, farm waste, animal droppings
Layer 30 cm Agriculture wastes, farm waste, animal droppings (application of earthworm over this bed)
Layer 5 cm Coarse sand
Layer 10 cm Broken bricks / pebbles
* Spraying of water is done on each layer
vii) Collection of earthworms
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.
viii) Introduction of worms in to beds
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.
ix) Vermicomposting mechanism
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.
x) Harvesting of Vermicompost and storage
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.
xi) Harvest of worm biomass
The worms and its cocoon are to be collected by sieving and used for subsequent