Agriculture is crucial to economic growth and accounts for one-third of global gross-domestic product (GDP). At global level industrial agriculture system currently dominates. The current agriculture system has shown an adverse effect on the ecological equilibrium, and threatened the health of people and the planet. It accounts for 70% of water use and generates unsustainable levels of pollution and waste. This has led a formidable demand for change in agricultural policy and regulatory reform. The public awareness of the problems caused by conventional agriculture system has built extensive support for sustainable agriculture. Sustainable agriculture can be defined as the farming systems and government policies that develop long-term positive impacts on agricultural profitability, environmental quality, food sufficiency, quality and affordability. It includes successful management of resources for agriculture to satisfy the changing human needs, while conserving and maintaining the natural resource base for long term economic growth and avoiding environmental degradation. It mainly aims at minimizing greenhouse gas emission, Conservation of ecosystem, Protection of public health and economic viability of Farmers.
Organic farming is intimately connected and provides an appropriate approach to meet to every principle of sustainable development. It is an ecological production management system that restore and maintain ecological harmony. It promotes and enhances biodiversity, biological cycles and soil biological activity by largely excluding the use of synthetic inputs such as chemical fertilizers, pesticides, hormones, feed additives etc.
Crop rotation: It is a systematic arrangement for the growing of different crops in a more or loss regular sequence on the same land covering a period of two years or more. Soil fertility management, weed, insect and disease control. Legumes are essential in any rotation.
Crop Residue: Incorporation of crop residues e.g. Wheat and Rice straw, as such or inoculated with fungal species has beneficial effects on crop yields and improvement in physico-chemical properties of soil.
Organic manure: Bulky organic manure:
- FYM: well-decomposed mixture of dung, urine, farm litter and left over or used up materials from roughages or fodder fed to the cattle.
- Composting: It is a natural biological process of recycling, carried out under controlled conditions. In this process, various microorganisms, including bacteria and fungi, break down organic matter into simpler substances. The decomposed organic matter is known as compost. It is a key ingredient in organic farming. Compost is also known as The Gardener’s Gold because as it is rich in nutrients , helps in erosion control ,act as a soil conditioner and natural pesticide for soil.
There are three types of composting aerobic composting, anaerobic composting and Vermicomposting. The quality of the compost depends upon C: N ratio of organic residues, Size of residue, Moisture and temperature in the compost bed, pH , microbial inoculants and amendment with rock minerals. The optimal C:N ratio for composting is 30-40 . Material having high C:N ratio (>40), can be mixed with activated sewage sludge, legume residue, aquatic weeds, slaughter house wastes to maintain proper C:N. The most desirable particle size is 3-5 cm. The optimum moisture content is 50-60% for aerobic composting. Neutral pH. is required for most of the micro organisms
- Mesophilic bacteria are involved in consuming readily degradable carbohydrates and proteins. Thermophilic bacteria attack lipid and hemicellulose.
- Actinomycetes such as Thermonosopra curvata and many fungi involved in cellulose decomposition.
- Preparation sawdust compost with inoculation of cellulolytic fungi Coprinus phemerus hasten the composting from 1-2 years to 3 months.
- Vermicomposting (Latin vermes= worms) is a simple process of composting, in which organic matter is recycled into nutrient rich compost using certain species of earthworms The major constituents of vermicompost includes essential macro and micro nutrients, enzymes, vitamins, antibiotics, humic acid and growth hormones.
There are 3 main types of earthworm suitable for vermicompost being the Anecic, Endogeic
and Epigeic species of worms.
- Anecic Worms – anecic worms feed at or near too the soil surface on plant litter or dead roots and other plant debris. They are usually larger worms that build permanent horizontal and vertical burrows in the soil
- Endogeic Worms – endogeic worms spend most of their time below the surface in the mineral layers of soil burrowing constantly and rarely come to the surface
- Epigeic Worms – epigeic worms are surface dwellers and feed on the decayed organic materials found on the soil . Epigeics used in vermicomposting are called red earthworms (Eisenia foetida), also known as red wiggler’s, manure worms, red hybrid or tiger worms due to their relatively high tolerance of environmental variations.
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Epigeic Species (Tiger worm, red wiggler, manure worm, compost worm) epi = top; geic = earth |
Small size (1 – 7 cm) and uniformly pigmented (red brown pigment), lives in litters and consumes decomposable organic matter e.g. Eisenia foetida, perionyx excavatus |
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Endogeic Species (Topsoil dweller) endo = in or internal; geic = earth |
Small to large in size (2-12 cm), weakly pigmented, lives in burrows in organic mineral complex of soil, consumes soil e.g Apprrectodea caligiginosa, Octolasion cyaneum |
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Anecic Species (Subsoil dweller) |
Very large in size (8-15 cm), brown pigment interiorly and dorsally, lives in deep vertical burrow in soil, but feeds on litter, casting on surface. e.g. Lumbricus terrestris |
- Green Manuring: practice of ploughing and incorporation of undercomposed green plant tissues for the purpose of improving physical structure as well as fertility of the soil. Examples: Sunhemp, Dhaincha Clusterbean, Cowpea, Berseem
Concentrated Organic Manure: Organic matter containing higher percentage of essential plant nutrients such as nitrogen, phosphorous and potash, as compared to bulky organic manures.
Made from raw materials of animal or plant origin.Examples: oilcakes, blood meal, fishmeal, meat meal and horn and hoof meal.
Bio fertilizer (also bio-fertilizer) is a substance which contains living microorganisms which, when applied to seeds, plant surfaces, or soil, colonize the rhizosphere or the interior of the plant and promotes growth by increasing the supply or availability of primary nutrients to the host plant.
Biofertilizers include the following:
- symbiotic nitrogen fixers, Rhizobium spp.( R. leguminosarum, R. lupini, R. trifolii, R. meliloti, R. phaseoli.)
- non-symbiotic, free-living nitrogen fixers (Azotobacter, Bacillus polymyxa, Clostridium, Beijerinckia. etc.);
- Algal biofertilizers (Anabaena, Nostoc, Aulosira, Totypothrix, Cylindrospermum, Stigonema. etc);
- phosphate-solubilising bacteria;
- mycorrhizae;
- organic fertilizers.
Bio-pesticide: Bio-pesticides are natural secondary metabolites, which include thousands of alkaloids, terpenoids, phenolics and minor secondary chemicals. Examples: Nicotine, Pyrethrum, Rotenone, Subabilla, Ryanin, Quassia, Margosa, Acorus etc. Some plants contain components that are toxic to insects. When these plant extracts applied on infested crops, they are called botanical pesticides. Azadirachtin (Neem), Pyrethrins ( Chrysanthemum sp.), Rotenone ( Derris sp.), Nicotine (Tobacco), Limonene (Citrus) have been used as botanical pesticides.Botanical pesticides are generally highly bio-degradable so that they become inactive within hours or a few days. This reduces again the negative impact on beneficial organisms and they are environmentally safe compared to chemical pesticides
Need and Benefits of Organic farming . Export of organic outputs fetches high prices with 10% more price for final produce because of their health benefits. Effectively, they result in an inflow of profitable foreign currency reserves.Maintaining animals for compost provides additional income from milk. The products are healthier and posses optimal nutritional value as compared to the traditionally grown counterparts . It also shows increases in carbon absorption by up to 55 %, and water holding capacity of soil by 10 %.
Future Prospects
Organic Farming has grown almost 25-30% per year during last 10 years. In spite of recession fears, the growth of organic farming is going unaffected. With the increasing awareness about the safety and quality of foods, long term sustainability of the system and accumulating evidences of being equally productive, the organic farming has emerged as an alternative system of farming which not only address the quality and sustainability concerns, but also ensures a debt free, profitable livelihood option.To provide the means of evaluation of certification programmes for organic agriculture and products as per the approved criteria. The National Programme for Organic Production (NPOP) provides an institutional mechanism for implementation of National Standards for Organic Production through National Accreditation Policy and Programme. It is an authoritative body that defines policies, standards and checks whether a certification system is operating according to standards or not.