Effect of Crop Establishment Methods and Weed Management Practices on Productivity and Bioenergetics of Rice

Background: SRI and aerobic rice are one of the techniques of growing rice under water scarcity areas where meeting water requirement is becoming a global threat. Weeds are another threat to yield of rice irrespective of different establishment methods. Until checked, it can decline rice yield and quality up to more than 70%. SRI and aerobic rice have different densities of weeds and integrated weed management can be applied to suppress the weeds. Considering the current scenario, research was conducted to investigate growth, yield and bioenergetics of rice under different establishment methods and weed management. Methods: The experiment entitled “Effect of crop establishment methods and weed management practices on productivity and bioenergetics of rice” was carried out in split plot design with main plots, viz., M1- aerobic rice (AR) and M2- system of rice intensification (SRI) and five subplots W1- pre-emergence (pendimethalin @1 kg a.i ha-1) fb post-emergence (bispyribac-sodium @20g a.i ha-1) (PE+POE), W2- pre-emergence (pendimethalin @1 kg a.i ha-1) fb cono weeding at 15, 30, and 45 DAT/ DAS (PE+CW), W3- weed free (WF), W4- weedy check (WC), W5- stale seedbed followed by post-emergence herbicide (bispyribac-sodium 10% SC 20 g a.i ha-1) (SSB+POE) in split plot design with three replications taking the variety ‘Pusa Basmati-1121’ as a test crop. Result: Among the establishment methods, SRI recorded significantly higher growth attributes like plant height and dry matter production and yield attributes like number of panicles per hill, panicle length, number of grains per panicle, test weight, grain yield, straw yield, biological yield, and harvest index. Among the weed management treatments, WF recorded significantly higher growth attributes like plant height, number of tillers per hill, dry matter production and yield attributes like number of panicles per hill, panicle length, number of grains per panicle, test weight, grain yield, straw yield, biological yield, and harvest index that was followed by treatment PE+CW. Maximum net return and B:C ratio was observed in the treatment combinations M2W2- SRI + (PE+CW). The maximum total energy input was found in the treatment combination M1W1- AR+ (PE+POE) and the maximum total energy output was found in the treatment combination M2W3- SRI + WF. The energy intensiveness was observed to be maximum in the treatment combination M1W4- AR + WC and the maximum energy efficiency index was observed in the treatment combination M2W3- SRI+WF.