Analysis of the Combining Ability and Heritability of Main Economic Characters in Transgenic Hybrid Rice

Four hybrid rice restorer lines with transferred anti-fungal protein genes and two non-transgenic counterparts, and five male sterile lines were used in a 5×6 NCII cross design, and the combining ability and heritability of their 12 agronomic characters were investigated. The additive effect appeared to play a predominant role in plant height (PH), panicle length (PL), number of panicles (NP), grain weight of plant (GWP), chalky rice rate, chalkiness and gel consistence, while non-additive variation played a major role in seed setting rate, whole head rice rate and pasting temperature. General combining ability varied in different characters of the transgenic restorer lines and in the same characters of the transgenic restorer lines and their non-transgenic counterparts. Of the parent lines, the transgenic restorer lien EF38 and the male sterile line 310S had the highest general combining ability. Of the cross combinations of transgenic lines, Peiai64S/EF84 and Zhenshan97A/EF29 had the highest specific combining ability for most characters studied. Plant height, panicle length, grain weight per plant, chalky rice rate and chalkiness showed high heritability (60%) while the heritability of seed setting rate, whole head rice rate and pasting temperature was relatively low so they should be selected in advanced generations in breeding.