ESTIMATION OF HETEROSIS FOR YIELD AND YIELD RELATED TRAITS IN RICE (Oryza sativa L.)

Hybrid rice technology is one of the most important and practically feasible technologies to enhance the rice productivity. This study was conducted to assess the hybrids for per se performance and heterosis with respect to yield and yield related traits to identify best hybrid combinations for commercial utilization. Result indicated that the magnitude of heterosis for grain yield over better parent was significantly superior to 21 hybrids with highest value of 93.3% in Pusa 6A x Akshaya Dhan. Eighteen hybrids showed significant positive heterosis over standard variety (BPT 5204) with the highest value of 66.9% in Pusa 6A x Akshaya Dhan cross for grain yield plant(-1). Out of 32 hybrids, 12 showed significant positive heterosis over standard hybrid (Arize-6444) with highest value of 34.8% in Pusa 6A x Akshaya Dhan for grain yield plant(-1). Top two higher yield heterotic crosses over the standard variety (BPT 5204) were Pusa 6A x Akshaya Dhan (66.9%) and IR79156A x MTU-7029 (60.1%). These 2 hybrids also exhibited significant positive yield heterosis over standard hybrid (Arize 6444) 34.8% and 29.2% respectively. Both the hybrids also exhibited significant positive standard heterosis for almost all the desirable yield attributing traits and significant negative standard heterosis for days to 50% flowering and days to maturity. The top heterotic crosses viz., Pusa 6A x Akshaya Dhan, IR79156A x MTU-7029, Pusa 6A x MTU-7029, Pusa 6A x IET 22202 and IR79156A x Danteswari and others which expressed more than 20% standard heterosis for grain yield along with other desirable yield components need to be tested on larger scale for many assumption.