Analysis of genetic main effects and GE interaction effects for protein con
tent (PC) and protein index (PI) of indica rice (Oryza sativa L.) was condu
cted for two year experimental data by using a genetic model for quantitati
ve traits of seeds in cereal crops. Nine cytoplasmic male sterile lines or
maintainers as female parents and five restorer lines as male parents were
used for a NC II mating design in 1995 and 1996. The results indicated that
PC and PI traits were simultaneously controlled by genetic main effects as
well as GE interaction effects. For PC and PI of rice, the embryo interact
ion effects (embryo additive and dominance interaction effects) were import
ant as effects of triploid endosperm, cytoplasm and diploid maternal plant.
The estimates of narrow-sense heritability for PC and PI of rice were 85.3
% and 77.9%, respectively. The interaction heritability was found to be lar
ger than the general heritability for PC and PI of rice. Significant relati
onships for components of different genetic effects between PC and PI were
found. The GE interaction covariances tended to be positive.