Allelopathic Effect of Cocklebur Extract on the Fertility Status of Soil in Transplanted Rice by Controlling Weed

摘要

Nutrient status plays a sine quo non role in maintaining the fertility of any soil. All the soil and plant indices are directly or indirectly related to it. In this experiment the use of xanthium is taken as key indicator for not just control over theprominent weeds of rice but this reduction of weed intensity thereby increase the nutrient reserves in the soil. In rice, weed control at early stage is imperative for realizing desired level of productivity. Here extraction from cocklebur is taken as aweed management tool to find out the effect of varying rates of Xanthium strumarium extract through different solvents(petroleum ether, methanol and water extract @1000mg L'^OOOmg L'1 and 3000mg V each respectively) on dry weight of weed, nutrient content and removal by rice plant. The experiment was laid out in a randomized complete block design with twelve treatments replicated thrice on variety HUR 3022 including butachlor, pretilachlor and control. The nutrient availability was measured in terms ofits content of the varied treatments and its uptake of nutrient in soil and plant at 30, 60 and 90 days after transplanting and at harvest. The application of petroleum ether extract @ 3000 mg L1 of X. strumarium was found to having higher nutrient status in rice with lower status in weed ultimately controlling the most relative weed of rice i.e. Echinocloa spp. having the nutrient reserves in the soil as well as crop plant.