Organic Farming is defined as the production system, which avoids or largely excludes the use of synthetically compounded fertilizers, growth regulators, pesticides and livestock feed additives. Organic farming mostly relies upon crop rotation, animal manures, legumes, green manures, crop residues, off- farm organic wastes, mechanical cultivation mineral bearing rocks and several other aspects of biological control to supply essential pant nutrients, control pest, weeds and other insects and most importantly to maintain the soil productivity.

There are several factors that organic farming favours. Some are enlisted below:

1. Integrated pest management for pest control
2. Tillage that minimizes the soil erosion even it is more expensive
3. Reliance on animal manures and green manures wit minimal input of inorganic fertilizers.
4. Management systems such as crop rotations that help to control weeds and disease organisms

Compost Making

It is the only process which provides for recycling of the organic matter(residues). In other words, compost making is the biochemical degradation of the organic matter to yield a sanitary soil supplement.  This process can handle garbage and other organic refuse except plastic it includes sewage sludge and waste from certain industrial operations such as raw and paper mills. Compost fertilizers prepared can be later used for agricultural purpose. The biodegradable wastes such as animal and vegetable wastes, lawn cutting, garden trimming, leaves, etc should be used for preparing compost by adding to it synthetic nitrogen, phosphorous and potash fertilizers.

Methods of compost preparation are:

• Pit method
• Heap method

The pit size of 5m2m pit can contain about 10-ton prepared compost. The length and width of the pit can vary according to the convenience but the depth should be either 1m or less if water logging is a problem. After every layer, inoculums, lime, complexal and water should be sprayed over the composting material. Besides prepared compost, poultry manure and ash manure can also be used as the inoculums.

Insect Pest Management

Biological pesticides are being considered asenvironmentally safe, selective, biodegradable, economical and renewable alternative for usein organic farming system.Most of the synthetic organic insecticides having high toxicity to pest species are often evenmore toxic to the beneficial insects like spiders, ladybird beetle and earthworms. The selection of insecticides for use musttake account their toxicity to animals, human beings and useful organism, their persistence inair, water, soil and overall environmentalimpact of their use on agricultural crops.

There are several methods for the management of Insect pests. They are:

1. Cultural method
2. Clean cultivation; provides less chances to breed and survive the insect
3. Crop rotation and ploughing; potato tuber moth’s population is reduced if crop is
   not grown there for few years. Sugarcane borer, whiteflies, and black bug aregreater on ratoon crop than newly planted crop
4. Variation in time of planting e.g. Early planted rice is saved from rice borer
5. Proper use of fertilizers and irrigation
6. Use of resistant varieties
7. Trap crop and intercrops
8. Pruning
9. Mechanical and physical control:

Hand picking of larger size insects e.g. Eggs andlarvae of cabbage butterflies and larvae of mustard saw fly.

1. Legal control
2. Biological control; Parasites and predators. Woolyaphids are controlled by aparasite Apanteles glomerates. Similarly, ladybird beetle, syrphids, chrysopa,Nabis, Mantidscan prey on number of insects
3. Biopesticides
4. Bacteria- Bacillus thuringiensis
5. Fungi- Beauveria, Entomophthora
6. Virus- Nuclear polyhedrosis Virus (NPV)
7. Use of pheromones and hormones; Potato tuber moth
8. Use of attractants, repellents and sterilant
9. Botanical pesticides; Margosom a neem product @ 1.5 ml/litre against aphids,
   whiteflies, jassids, mites and scale insects.
10. Traditional method; Dry wood ash applied during early morning hours gave better
    protection than other time of day. Wood ash soaked in ether for a period of overnight andsieved through fine cloth and mixed with soap water then spray on
    vegetable crops gives good protection against aphids and soft bodied insects

Bio-pesticides for Insect Pest and Disease Management

Bio-pesticides are natural plant products that belong to the so-called secondary metabolites,
which include alkaloid, terpenoids phenolics and minor secondary chemicals. Every plant
species has developed in built unique chemical complex structure that protects it from pests.
The plant kingdom offers us a diverse array of complex chemical structure and almost every
imaginable biological activity.

Vermi-compost
It is a method of making compost with the use of earthworms, which generally live in soil, eat
bio-mass and excrete it in digested form. This compost is generally called vermi-compost. It is
estimated that 1899 worms which is an ideal population for one sq. meter can feed on 80
tonnes of humus per year. To prepare an ideal vermi-compost, the following procedure is
adopted.

• Each shed measuring 20ft x 80 ft is to be constructed with the help of locally available
  material like bamboos, stems of trees etc. A hut type structure is built with the help of these
  The roof is made from dried grass, Typha leaves, bamboo sticks, etc., in such a waythat the hut may be protected from rain water and sun heat. Each hut may accommodate atleast four vermin-beds of 3 ft. width.
• These beds are prepared by putting 2 to 3 cm thick layer of farm manure as first layer
  followed by 10 to 15 cm of bio-mass with 200-250 worms per sq. ft. collected locally may beadded and the bed should be kept sufficiently moist. This layer should be followed by a layerof 10 to 15 cm of half-digested cow-dung layer which should be covered by a layer of leaves,trash etc., and water is sprinkled on the entire bed. The bed may be covered with palmleaves or coconut leaves or with any indigenous material. The pits should be kept constantlymoist but never flooded.
• A month later, the covered leaves should be removed and layers of organic waste not
  exceeding 6-7 cm should be added every alternate day. Watering should continue with eachfilling. When the pit is nearly full to a height of one metre, the material should be turneddown to provide aeration. After a month, the heap will be ready for harvest with good qualityvermi-compost. The dug out vermi-compost should be heaped in an open place. The wormswill find way to the bottom of the heap. The vermi-compost from the top can be removed,dried and sieved for application in the field. The compost can also be enriched withmicronutrients bacteria etc. by adding them externally, 16 tonnes of compost can becontained from 4 beds in 30 days after four months gestation.

Other Methods of Organic Manures are

• Green manure in-situ
• Green leaf manure ex-situ
• Concentrates organic manures; cakes, meat meal, bone meal
• Bio fertilizers; Rhizobium, Azotobactor, Blue green algae, Azolla, Mycorrhizae etc.

Organic farming is an eco-friendly approach to sustainable agriculture whereas
application of synthetically compounded fertilizers, growth regulators, livestock feed
additives and pesticides cause environmental and health hazards. The use of pesticides,
especially on vegetable crops such as brinjal and tomato has carcinogenic effect on human
health. The IPM is one of the best ecological approaches that minimize the cost of farming by
using bio-fertilizers and pesticides and at the same time it increases quality of the products.
It plays a tool for safeguarding environment by conserving agro biodiversity in farmer’s field.

Sadikshya Pokharel 

psadicxa8@gmail.com