Effect of Moisture Conservation Practices on Yield and Water Use Efficiency (WUE) of Direct Seeded Rice - Greengram Cropping Sequence in Rainfed Ecosystem of Assam

摘要

In India, the development issue of rainfed agriculture assumes critical importance as it covers about 56 of total cultivated area of the country. The conventional method of rice cultivation with irrigation is at threat due to declining availability of water. A field experiment on sandy loam soil was conducted during autumn and kharif season of 2016 and 2017 at Biswanath College of Agriculture, Assam Agricultural University, Biswanath Chariali to study the effect of moisture conservation practices interms of land configuration and residue management on yield performance and water use efficiency (WUE) in direct seeded ricegreengram cropping sequence. The experiment was conducted in RBD with six moisture conservation practices (flatbed with crop residue incorporation, flatbed without crop residue incorporation, broad bed furrow (BBF) 60-30 cm with residue incorporation, BBF 60-30 cm without residue incorporation, BBF 120-30 cm with residue incorporation and BBF 120-30 cm without residue incorporation) with 4 replications. The yield attributes, seed and stover yield (q ha1) of both the crop viz. direct seeded rice and green gram were better in BBF as compared to flatbed method of moisture conservation. Among the BBF, the crop residue incorporated treatments performed better over no residue incorporation. The total water use (mm) was 2.76 higher and WUE was 2.45 higher in the moisture conservation practices of BBF with residue incorporation irrespective of size of the bed over flat beds with residue incorporation treatments. The equivalent yield of the direct seeded rice-greengram system was 24.62 higher in BBF irrespective of the bed size over flatbed and between the bed size of 60-30 cm and 120-30 cm. BBF of 120-30 cm size bed showed comparatively higher net return of Rs. 30,598/ha with a B:C ratio of 1.69.