Impact of planting methods biochar and polyacrylamide on soil properties crop yield and water productivity in rice wheat system

Abstract

A field experiment was conducted at Faculty of Agriculture, Sher e Kashmir University of Agricultural Science and Technology of Jammu, during 2020-2022 on sandy clay loam soils. The soilof the experimental field was slightly alkaline in reaction, low in available N and medium in available P and K. The experiment comprised of two cropplanting methods viz.system of riceintensification (SRI) and conventional flooded rice (CFR) assigned to main plots and sixbiochar and polymer treatments viz.T1: B0 P0 (Control), T2: B0P10 (10 kg PAM per hectare), T3: B5P0 (5 tons biochar per hectare), T4: B5P10 (5 tons biochar per hectare + 10 kg PAM per hectare), T5: B10P0 (10 tons biochar per hectare), T6: B10P10 (10 tons biochar per hectare + 10 kg PAM per hectare)assignedto sub-plots replicated thrice. The experiment was laid out in split plot design. Thevariety used was Basmati-370 (Rice) and HD-3086 (Wheat). newlineThe application of biochar and PAM accounted for maximum N (239.10 kg ha-1), P (14.23kg ha-1), K (153.75kg ha-1) and uptake of N (84.72kg ha-1), P (23.14kg ha-1), K (106.81kg ha-1) under SRI. However, in wheat, planting methods had no significant effect on available N, P, K and nutrient uptake. The results revealed that grain yield of rice under SRI (2702 kg ha-1) was significantly higher than CFR (2352 kg ha-1) averaged during both the seasons. Among different treatments, the application of biochar and PAM significantly yield attributes as well as root volume in rice wheat system.It was also observed that the SRI along with the combination of B10P10resulted in better water productivity during the course of experimentation. The highest BC ratio was observed in SRI as 1.75 and B10P10 treatment as 1.86. newline newline