Weeds, castor yield attributes and yield as influenced by weed management

A field experiment was conducted at Agricultural College Farm, Bapatla, Andhra Pradesh during Kharif 2020 to assess the effect of weed management treatments on weeds, yield attributes and yield of castor. The hand weeding twice at 20 and 40 days after seeding (DAS) recorded the lowest density and biomass of all the categories of weeds as well as the highest weed control efficiency, yield attributes and yield of castor. Next best treatments were pre-emergence application (PE) of alachlor 1.5 kg/ha followed by (fb) post-emergence application (PoE) chlorimuron-ethyl 10 g + propaquizafop 63 g/ha at 30 DAS or alachlor 1.5 kg/ha PE fb application of halosulfuron-methyl 67.5 g + propaquizafop 63 g/ha PoE at 30 DAS. The benefit cost ratio was highest with alachlor 1.5 kg/ha PE fb halosulfuron-methyl 67.5 g + propaquizafop 63 g/ha PoE at 30 DAS.