Productivity and profitability of sorghum-wheat cropping system in saline soils as influenced by conservation agriculture practices

摘要

A study was initiated for evaluation of sorghum-wheat system productivity and profitability with tillage, deficit saline irrigation and mulch under saline conditions during 2015-2017. The experiment was conducted in split-plot design with three replications. Three tillage treatments viz. reduced tillage-zero tillage (RT), conventional tillage-conventional tillage (CT) and zero tillage-zero tillage (ZT) were taken in main plot and combination of rice straw mulch (0 and 5 Mg ha(-1)) and saline irrigation (EC 8.0 dS m(-1)) with 100, 80 and 60 water requirement of wheat was applied in subplots. The deficit irrigation (60) with mulch showed significantly greater soil moisture content compared to no mulch counterpart in RT and ZT. The ZT recorded lower ECe compared to RT and CT. The deficit irrigation (60) recorded the lowest value of ECe. Mulch reduced the salt load and increased the available N, P and K content in the soil compared to no mulch. The system productivity (SP) of sorghum-wheat cropping system was 3.8 greater (P< 0.05) under rice straw mulch. The deficit saline irrigation at 60 showed the maximum SP compared to 100 and 80 water requirement. Net return and benefit cost ratio was also higher for the improved management practices involving reduced tillage, deficit irrigation (60) and mulching. Therefore, under limited freshwater availability in salt-affected soils, deficit irrigation with mulching and reduced tillage was found most beneficial option for increasing productivity and profitability of sorghum-wheat cropping system.