Combining ability for yield and quality characters in rice (Oryza sativa L.)

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 IET 8887 (2.34 t ha-1) followed by IET 9219 (2.29 t ha-1), IET 8886 (2.26 t ha-1), Rasi (2.24 t ha-1), Vikas (2.22 t ha-1) and IET 9994 (2.19 t ha-1) while the lowest grain yield was recorded in IET-9818 (1.84 t ha-1). Seed rates increased grain yield significantly up to 250 kg ha-1 (2.61 t ha-1) but 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. IET 8887 and IET 9994 recorded higher net returns of Rs. 810 ha-1 and Rs.610 ha-1, respectively, while 250 kg seed ha-1 in variety recorded highest net returns of Rs. 1,640 ha-1.