Increasing productivity of rainfed rice-based systems in NW Bangladesh: establishment nutrient and weed management

摘要

Results from four cycles of a rice-chickpea rotation demonstrated that rice productivity can be increased and the rice harvested earlier in the drought-prone Barind Tract of Bangladesh by switching from transplanting (TPR) to direct-seeding (DSR). Dual objectives of the switch to direct seeding are to avoid terminal drought in rice and lengthen the window when soil moisture remains adequate for post-rice crop establishment. Direct-seeded rice yields were equivalent to or increased compared to transplanting. Yields were elevated by application of nitrogen fertiliser and weeds were adequately controlled by pre-emergence application of oxadiazon. The abundance of some species, notably Cynodon dactylon, Echinochloa crus-galli and Fimbrystilis miliacea increased under DSR. Occasional rotation of DSR with TRP may prevent these weeds becoming long-term problems.