Genetic effects on Fe, Zn, Mn and P contents in Indica black pericarp rice and their genetic correlations with grain characteristics

Complete diallel crosses with 6 varieties of black pericarp rice and 1 variety of aromatic white rice were conducted to analyze the seed, maternal and cytoplasmic genetic effects on Fe, Zn, Mn and P contents in kernels by using a genetic model for quantitative traits of seeds in parents and their F(1)s and F(2)s. Seed, maternal as well as cytoplasmic genetic effects controlled the contents of all the mineral elements studied. The seed genetic effects were found to be more influential than the maternal genetic effects on Fe, Zn, Mn contents. Seed additive effects constituted a major component of the genetic effects whereas the seed additive along with maternal additive and dominant effects formed the main part in the inheritance of P content. The heritabilities of seed effects on all the mineral contents were highly significant (p < 0.01). The estimated values of narrow-sense heritabilites of seed genetic effects on Fe, Zn and Mn contents were high, while those of seed and maternal effects on P content were intermediate. Single plant selection and single grain selection based on the seed mineral element contents were advocated to improve the hybrid progeny. Genetic correlations showed that there existed significant genetic correlations of seed additive, seed dominance, cytoplasm, maternal additive and maternal dominance between grain characteristics such as 100-grain weight, grain length, grain width, grain shape and mineral elements Fe, Zn, Mn and P contents. Indirect selection of grain characteristics may be one of the breeding methods to select for higher contents of Fe, Zn, Mn and P in black pericarp indica rice.