Studies on inbreeding depression from F1 to F3 generation in some intervarietal crosses of rice (Oryza sativa L.) in terai region of West Bengal

A field experiment was conducted to study the inbreeding depression of some intervarietal crosses of rice, from F1 to F3 generation in the terai region of west Bengal. For this purpose five stable genotypes of rice namely, IET-4786, BR-28, MTU-1010, Annada and IET-21255 were selected on the basis of their mean performances in this region of West Bengal. Involving these five parents, Four crosses were made to study the performance of the F1, F2 and F3 generations for grain yield per plant, and other yield contributing characters. It was quite interesting to note that out of those four crosses, one cross namely IET-4786 × MTU-1010 gave a consistent performance in all the 3 generations for grain yield per plant. As a matter of fact the inbreeding depression F1 to F2, and F1 to F3 was non significant in this cross for for grain yield per plant, hence it was concluded that this cross could be tried to see its performance in few more advanced generations for grain yield per plant, and if its performance is found satisfactory over the generations, could be tried for its release in this region.