Analysis On The Gene Effects Of The Ear Traits Of Temperate × Tropical Crossess In Maize

Using temperate inbred lines and tropical subtropical inbred lines as parents, according to Hayman model and by means of the generation mean analysis, we studied the gene effects of the ear traits in 3 temperate × tropical crosses. The main result was as followed:(1) Additive e ffect, and dominant e ffect were detected in a 11 of the crosses. Epistatic effects were present in the inheritance of all characters under study. The heredity of all the traits conformed to the genetic model of the additive-dominance-epistasis.(2) There is significant difference between temperate inbred lines and tropical lines. The characteristics of longer ears, more number of kernel per rows, thinner ears and less kernel rows for the tropical germplasm and the significant heterosis in temperate x tropical crosses were found. It was maximum in grain yields and minimum in kernel rows.(3) According to genetic analysis, additive and dominance gene effects were positive for all traits of ears under study. Additive x additive was also positive for almost all traits. Dominance x Dominance was negative for ear length. Additive x dominance and dominance x dominance were all negative gene effects for kernel rows. Additive x dominance was negative for grain yields. But dominance x dominance was positive for grain yields.(4) Additive and dominance gene effects was dominate position, whose variance contributed to total genetic variance were 74.4%-93.5%. Epistasis was important for certain combination, whose variance made up 6.5%-25.6% in total genetic variance. As for all sorts of contribution of gene effects, difference existed among different traits. Dominant effect was maximum for number of kernel per rows. Contribution of additive was maximum for kernel rows. The dominant effect was more important than the additive one in ear length, ear diameter, number of kernel per row, grain yields. But it was opposite in kernel rows.