Longterm zero tillage and residue management practices on soil nutrient availability and productivity of pigeonpea under dryland conditions

Abstract

Conservation agriculture has potential for conserving the resources and enhancing productivity to achieve the goals of sustainable agriculture. Long term conservation agriculture experiment was started with main plot treatments include zero tillage raised and flat bed, with or without residue retention on surface, after six years reduced dose of nutrients as subplots at Agricultural Research Station, Bheemarayanagudi is situated in North Eastern Dry Zone (Zone-2) of Karnataka. The soil was red sandy loam. Every year same crop Pigeonpea was cultivated. The rainfall received during 2015 was 437.6 mm, which was 17.1 percent low compared to average. Rainfall received during 2016 was 398.2 mm, which was 24.56 percent low compared to average. Pooled results of the experiment revealed that zero tillage raised bed with residue retention produced higher seed and stalk yield, sustainable yield index, organic carbon and nutrient availability and uptake than other treatments. Among the nutrient doses 100 percent given higher yield and nutrient content and uptake, but economics net returns and B:C ratio were higher where zero nutrient doses. Finally, interaction of zero tillage raised bed with residue retention along with 100 percent application of nutrient dose produced higher yields but were on far with 75 and 50 percent of nutrient doses. Thus, in long term conservation agriculture practices, nutrient dose requirement can be reduced to 50 percent in pigeonpea grown under dryland conditions.