Mechanized weed management to enhance productivity in System of Rice Intensification (SRI)

Rice ecosystems including irrigated rice in India is infested with complex weed flora including semiaquatic and aquatic weeds which cause yield losses from 15 to 76% in rice crop. ICAR-Indian Institute of Rice Research (IIRR) under All India Co-ordinated Rice Improvement Programme (AICRIP) has conducted experiments across India (11 locations) to evaluate System of Rice Intensification (SRI) method, assessing their potential and the effects of individual SRI practices for enhancing productivity under different agro-ecological conditions compared to standard normal transplanting (NTP) method. SRI method recorded significantly higher grain yield (6.22 t/ha) followed by integrated crop management (ICM) (6.07 t/ha), standard practice of transplanting (5.60 t/ha) and direct seeding with drum seeder (5.13 t/ha). The effect of cono-weedings on grain yield indicated the superiority of 4 times cono weeding (10, 20, 30 and 40 DAT) which recorded better yields over two times cono weeding and the reduction in yield to the tune of 5.7–11.8% by 2 times cono weeding i.e. 10 and 20 DAT (5.7% less) and herbicide application (11.8% less), respectively. Based on multi-location testing, results indicated that SRI has the potential to enhance the productivity of the rice with reduced inputs in different agro-ecological situation and soil types across the country and weeding by cono weeder with reduction in drudgery of weeding in rice.