Genetic Studies on Some Earliness and Agronomic Characters in Advanced Generations in Bread Wheat (Triticum aestivum L.)

The early generation (F3 families) analysis measured the variance components of three crosses of five diverse parents. This work carried during three years 2010-13 at the experimental farm of Sakha Agricultural Research Station, Kafr El-Sheikh governorate, Egypt. The Data were recorded on days to heading, days to maturity, grain filling period and rate, plant height, number of spikes per plant, number of kernels per spike, 100-kernel weight and grain yield. The F3 families had highly significant differences in most cases. The ranges of the performance of the F3 families exceeded the limits of the minus and plus directions of their parents for most characters, showing the ability of selection for the desirable directions for these characters. The magnitude of genetic variance among the F3 families exceeded corresponding environmental variance, while the environmental variance was higher than or almost equal to the corresponding genetic variance among plants within families for most characters. The additive and dominance variances were important in all cases. The broad and narrow sense heritability and genetic advance estimates were relatively medium to high for most characters. 5% of plants for each cross were selected for ealry mature and high yielding to evaluate in sperate experment in the next season.