Tillage effect on soil organic carbon, microbial biomass carbon and crop yield in spring wheat-field pea rotation

This research was conducted to assess the influence of long-term tillage system on soil organic carbon, microbial biomass carbon, root biomass and crop yield in spring wheat-field pea rotation fields in a rainfed semi-arid environment from 2013 through 2015. The treatments were; conventional tillage with stubble removed (T); no-till with stubble removed (NT); no-till with stubble retained (NTS) and conventional tillage with stubble incorporated (TS) arranged in a randomised complete block design with three replicates. The soil organic carbon in NTS increased by 16% and 14% over T and NT. Compared with the T and NT, NTS increased soil microbial biomass carbon by 42% and 38% in 0-30 cm depth, respectively. Root biomass was significantly increased in NTS by 47% and 54% over T and NT, respectively. Across the three years, NTS had an average grain yield of 53% and 41% higher than T and NT, respectively. Compared with NTS, T and NT decreased root biomass by 54% and 48%, respectively. In view of the limited and erratic biomass production in this region, integration of no-till with straw mulching is recommended for soil fertility improvement, environmental quality and sustainable crop production.