Effect of cultivars and seed rates on weed dynamics and grain yield of rice under wet seeded condition

摘要

Field trials were conducted during wet season 2000 and dry season 2001 to study the effect of cultivars and seed rates on grain yield in wet seeded rice. Among the varieties, mean maximum grain yield was recorded in IET8887 (2.34 t ha~(-1)) followed by IET9219 (2.291 ha~(-1)), IET8886 (2.261 ha~(-1)), Rasi (2.241 ha~(-1)), Vikas (2.22 t ha~(-1)) and IET 9994 (2.191 ha~(-1)) while the lowest grain yield was recorded in IET 9818(1.841 ha~(-1)). Seed rates increased grain yield significantly up to 250 kg ha~(-1) (2.611 ha~(-1)) further increase in seed rate did not increase grain yield proportionately. Weed dry matter production reduced significantly up to 300 kg seed ha~(-1) (57.41 g). Significantly maximum weed dry matter was recorded in c.v. IET 9818. IET8887 and IET 9994 recorded higher net returns of Rs. 810 ha~(-1) and Rs.610 ha~(-1) respectively, Among different seed rates, mean maximum net returns of Rs. 1640 ha~(-1) was recorded by the seed rate of 250 kg ha~(-1).