| Environmentally sound technologies for women in agriculture |
Pesticides are dangerous to human health: 22,000 people die in developing countries each year from pesticide poisoning.
High dosages of fertilizers and liberal use of synthetic pesticides can pollute water, air, and soil. Pests can develop resistance to pesticides and previously unimportant pests can emerge
The health of the soil is also adversely affected. Certain micronutrients such as zinc, copper, and iron can become deficient in the soil over a period of time. As a result, it becomes increasingly difficult for farmers to sustain high yields year after year.
How can we face this critical dilemma of consistently obtaining high crop yields without polluting soil, air, and water, and without depleting soil fertility? The answer perhaps lies
In organic farming.
What is organic farming?
The aim of organic farming is to increase productivity with minimum reliance on chemicals, while at the same time conserving resources. It is a rediscovery of the practices of our ancestors, but with a modern and scientific outlook. It nurtures the soil rather than just a particular crop.
The use of synthetic chemicals is minimized (to the level of bare necessity). There is a greater reliance on conservation and use of all resources available on the farm, including animal, human, and plant wastes.
The goal of organic farming is to achieve stability without sacrificing high production and without polluting water, soil, and air.
It requires a multidimensional approach emolovina many practices.
Integrated nutrient management
- Use minimum tillage practices to conserve soil organic matter and biotic life including earthworms.
- Convert all available biomass on the farm into compost rather than burning or otherwise wasting it. (See Compost-making and Vermicomposting.)
- Add at least 2-3 tonnes of compost per hectare annually. The ideal is 10 tonnes per hectare.
- Apply green manure to the fields after every second or third year. For instance, prunings from gliricidia or other leguminous trees planted on bunds can be incorporated in the rice fields at the time of puddling. This can reduce or eliminate the need for artificial fertilizers.
Incorporate leguminous plant material into the soil.
- Make up soil deficiencies, if any, (on a soil test basis) by applying minerals such as rock phosphate, gypsum, and pyrites.
- Manage weeds using nonchemical methods, rather than trying to eradicate weeds. (See Nonchemical methods of weed control.)
- Leave the weeds taken out of the fields to form a mulch and to decompose in the soil itself Or use them for making compost.
- Adopt suitable crop rotations, mixed cropping and intercropping, instead of growing one and the same crop year after year. This uses soil layers, space, and sunlight differently..
- Include legumes in the rotation; inoculate them with rhizobium culture.
Integrated pest and disease management
Organic farming uses various practices to manage the pest population at a safe level (one that does not cause economic injury) rather than completely destroying them using synthetic chemicals.
These practices include the following:
- Invert the soil after harvesting a crop to expose pests.
- Clean bunds and channels of grasses which harbour pests.
- Grow pest-tolerant varieties.
- Sow the crops at the right time.
- Sow healthy seeds.
- Increase the seed rate so that uprooting insectand disease-infected plants later does not affect optimum plant populations.
- Hand-pick and destroy egg masses, gregarious larvae, caterpillars, and adult beetles.
- Use light traps.
- Apply sticky grease bands on fruit trees to stop insects from crawling up the trunk.
- Release insect parasites and predators, and apply biological control agents such as Bacillus thurigensis.
- When pesticides are used, restrict these to a few mainly plant-based pesticides: neem, karanj products, derris (also known as rotenone), and pyrethrum
Integrated soil and water management
Apply irrigation water efficiently to avoid wasting water and controlling soil erosion and loss of nutrients through runoff and leaching. For this:
- Irrigate your crops only when needed, use only the required amount of water. For instance, fields can be divided into small sections which can be irrigated separately.
- Do not apply excess water at any one time. Avoid leaching soil nutrients beyond the root zone.
- Keep your fields levelled.
- Consider constructing prefabricated concrete channels to avoid water seepage and leaching of nutrients.
- Harvest water by constructing bunds, channels, and tanks to store water for future use.
- Conserve water in the soil by using mulch, cultivating along the contour, and breaking the soil crust to slow the evaporation of water from the surface.
Contributors/Sources: Dr. V. N. Shroff, Mr. C. V. Sheshadri, Ms. Chitra Gandhi, Dr. W. R. Deshpande, and Dr. Jagdish Singh