Que 1. What is organic agriculture?
Ans: Organic agriculture is a holistic production management system which promotes and enhances agro-ecosystem health, including biodiversity, biological cycles, and soil biological activity. It emphasizes the use of management practices in preference to the use of off-farm inputs, taking into account that regional conditions require locally adapted systems. This is accomplished by using, where possible, agronomic, biological, and mechanical methods, as opposed to using synthetic materials, to fulfill any specific function within the system. (FAO/WHO Codex Alimentarius Commission, 1999).
Que 2. Can organic farming produce enough food for everybody?
Ans: The performance of organic farming on production depends on the previous agricultural management system. An over-simplification of the impact of conversion to organic agriculture on yields indicates that:
- In industrial countries, organic systems decrease yields; the range depends on the intensity of external input use before conversion;
- In the so-called Green Revolution areas (irrigated lands), conversion to organic agriculture usually leads to almost identical yields;
- In traditional rain-fed agriculture (with low-input external inputs), organic agriculture has the potential to increase yields.
Que 3. What is conservation agriculture?
Ans: Conservation agriculture is a concept for resource-saving agricultural crop production that strives to achieve acceptable profits together with high and sustained production levels while concurrently conserving the environment (FAO 2007). Conservation agriculture emphasizes that the soil is a living body, essential to sustain quality of life on the planet. In particular, it recognizes the importance of the upper 0-20 cm of soil as the most active zone, but also the zone most vulnerable to erosion and degradation. It is also the zone where human activities of land management have the most immediate, and potentially the greatest impact.
Basic principles of conservation agriculture
- reductions in tillage (ultimate goal-zero tillage or controlled till).
- retention of adequate amount of crop residues on the soil surface (ultimate goal – surface retention of sufficient crop residues to protect the soil from water run-off and erosion, improve water infiltration and reduce evaporation to improve water productivity, increase soil organic matter (SOM) and biological activity and enhance long term sustainability).
- crop rotations (ultimate goal – employ economically viable, diversified crop rotations to enhance soil biodiversity, take advantage of biological nitrogen fixation (BNF) and soil enhancing properties of different crops, reduce labor peaks and provide farmers with new risk management opportunities.
- Improved economic benefits and livelihoods from sustainable CA systems (ultimate goal - secure farm level economic viability and stability).
Que 4. What is the importance of critical period for weed control?
Ans: The critical period for weed control has been deﬁned in several ways. Zimdahl (1988) deﬁned it as a ‘‘span of time between that period after seeding or emergence when weed competition does not reduce crop yield and the time after which weed competition will no longer reduce crop yield.’’ It is a period in the crop growth cycle during which weeds must be controlled to prevent yield losses. Knowing the critical period for weed control is useful in making decisions on the need for and timing of weed control and in achieving efficient herbicide use from both biological and economic perspectives (Knezevic, 2002).
Que 5. What are the important rice based cropping sysyems?
Ans: Rice (Oryza Sativa L.) is the principal food crop of North Eastern Region of India occupying an area of about 3.5 m ha. The cropping intensity in the region is hardly about 120 %. Conventionally, after kharif rice, fields remain fallow in lowland, mainly due to excess moisture owing to seepage from surrounding hillocks in mid altitude. Draining water from rice field completely at physiological maturity (about 10 days before harvest) creates favourable condition for successful cultivation of rabi pulses like pea, lentil and oilseeds like toria. A simple drainage channel of 30 cm width and 30 cm depth at 5 m interval creates the desirable soil moisture situations.
In upland, after rice harvest no crop is cultivated due to severe moisture stress. The conventional tillage for sowing of rabi crop further aggravates the soil moisture problem by completely exposing the soil. With the help of zero tillage, the rabi crop can be grown directly in standing rice stubbles soon after the harvest of the rice crop. As the soil is not tilled, the rate of soil moisture loss is reduced and rabi crop can be grown successfully with conserved soil moisture and life saving irrigation. Soon after the rice crop harvest, sow toria/lentil crop can be grown.