Weed management in maize under rainfed organic farming system

Abstract

Field experiment was conducted under organic farming for three consecutive years during 2008–09 to 2010–11 to study the effect of different non-chemical weed management practices on productivity and weed infestation in maize in mid altitude (950 m MSL) of Meghalaya, India. Total eight treatment in three replication were evaluated on maize. Grain weight/cob of maize was maximum under mulching with fresh Eupatorium sp. biomass after earthing up at 30 days after sowing (DAS). The highest maize yield was recorded under mulching with fresh Eupatorium 10 t/ha, but it was statistically at par with two hand weeding (HW) at 20 and 40 DAS, weed free check and soybean green manure incorporation in situ + one HW. Two HW, soybean green manure incorporation + one HW and mechanical weeding (20 DAS) + one HW (after earthing up) were found to be effective in weed reduction in maize. Weed control efficiency was recorded maximum under two HW which was at par with mechanical weeding (20 DAS) + one HW. Available N, P, K and soil organic carbon concentration after 3-croppoing cycles were maximum under mulching with fresh Eupatorium 10 t/ha treatment followed by soybean green manuring + one HW (45 DAS) than those under other weed management practices. Thus, mulching with fresh Eupatorium (after earthing up) and soybean green manuring + one HW were the recommendable options for sustainable organic maize production under high rainfall hill ecosystem of North-East India.