Abstract: The heterosis of 61 two-line hybrids of rice were shown to be highly significant in ten agronomical characters.The average values of ten agronomic) characters in hybrids exceeded that of their parents and that of the parents with greater values.The transgressive heterosis and competitive heterosis were significant in such charaters as total grains per panicle,grain-to-straw ratio，filled grain number per panicle，grain weight per plant，while the heterosis of such characters, as the growth period duration，seeting percentage and weight of 1000-grains was weak.The results of path analysis indicated that among the 6 characters the filled grain number per plant showed the greatest effect on the grain weight per plant of Fl hybrids,and next to this characters the panicle number per plant, grain-to-straw ratio, seeting percentage, ear length and growth teriod duration showed more effect on it.

Key words: Two-line, Keng hybrid rice, Heterosis

CLC Number: 

• S511.22