M. I. Ali, S. Monira, M. Rashed, M. Salim, M. A. Salam and R. C. Das
Using a weed control scheme could assist in reducing potential production losses caused by weeds in paddy fields. Due to certain undesirable adverse effects, there is currently no realistic alternative to chemical weed suppression approaches in rice. The present research aimed to assess how various herbicide-based weed control techniques influenced the weed profile, and crop production of T. aman rice varieties. The study was done employing a randomized complete block design with 3 trials. The investigation comprised three aman rice cultivars and four weeds control techniques such as control, pre-emergence herbicide, early post emergence and post emergence herbicide. On research sites, ten weed types from 5 families were revealed. The grass weed Echinochloa gras-galli had the highest summed dominance ratio (SDR: 42.05%), while the sedges Scirpus mucronatus had the lowest SDR of 0.81%. Post-emergence herbicide application provided the lowest weed biomass and density at all sampling dates and produced the greatest seed yields (4.25 t ha-1), straw yield (5.41 t ha-1) and harvest index (43.87%) because of minimal crop-weed competition. In the case of interaction, BRRI dhan49 coupled with post emergence herbicide attained maximum output (4.80 t ha-1) followed by BRRI dhan49 with early post emergence. Due to ability for reducing weeds population, usage of post emergence herbicide could be considered as an efficient weed control approach in BRRI dhan49.
Keywords: Herbicide; Aman rice; Weed control; Yield.