Genetic Effects of Quality Protein Maize on Kernel Traits

Abstract

To efficiently use tropical hard quality protein maize (QPM) germplasm in enriching temperate QPM germplasm, improving kernel traits, and developing hard QPM hybrids, the genetic effects and heterosis of 8 QPM inbreds with different en-dosperm traits and their F1 and F2 progenies were evaluated via Griffing I diallel mating design. The hundred-kernel weight (HKW), hundred-kernel volume (HKV), endosperm modification (EM), and kernel density (KD) showed positive heterosis in F1 and F2 generations. EM showed differences in F1 reciprocal crosses, indicating obvious maternal effect. Correlation analysis showed that values of HKW, HKV, EM, and KD in F2 generation had the biggest correlation coefficients with the average parental values. Maternal effect was the main factor on HKW, HKV, and KD, while direct genetic effect was mainly on EM. Gene actions for HKW, HKV, EM, and KD were dominant, dominant, additive, and additive dominant, respectively. Cytoplasmic effect was little for the above 4 kernel traits suggesting that kernel traits are mainly controlled by nuclear genes.