Effect of preceding rice herbicide residue towards control of weeds and urdbean productivity in rice -Bhendi-urdbean sequence under high rainfall area

Abstract

Field experiment was conducted at Field Crops Research unit, ICAR- Central Island Research Institute, Bloomsdale, Port Blair during summer season, 2018. To study the preceding rice herbicide residual effect in control of weeds, growth and yield of urdbean in rice-bhendi-urdbean sequence under high rainfall area. At 20 DAS, grassy weeds (48.00 weeds/m2) were predominant species of weeds followed by sedges and broad leaf weeds of 29.67 and 22.67 nos./m2 respectively. Among the irrespective of weed control treatments, at 20 DAS, residual effect of 1.25 kg/ha butachlor at 3 DAP + manual weeding at 40 DAP in rice + two manual weeding on 20 and 40 DAS in both bhendi and urdbean recorded significantly lower grass, sedges, broad leaf weeds population and weed biomass of 11.67, 8.67, 6.67 weeds/m2 and 2.93, 2.02, 1.84 g/m2 respectively. Residual effect of 1.25 kg/ha butachlor applied at 3 DAP along with manual weeding at 40 DAP in rice + two manual weeding on 20 and 40 DAS in both bhendi and urdbean obtained 299 kg/ha higher seed yield as compared to weedy control.