Efficiency of Pedigree Selection in Bread Wheat under Drought Stress Conditions II – Yield and its component traits

Pedigree selection was practiced on two bread wheat populations, namely i.e. (Debeira x Sahel 1) as considered population I and (Sids 6 x Sahel 1) as considered population II. Experiments were conducted under drought stress conditions (at 12 % soil moisture content) in order to improve yield and its component traits (no. of spikes / plant, biological yield, grain yield / plant and 1000-grain weight). Variance analysis revealed that all F3 families in both populations were highly significantly affected by soil moisture content. Also, significant or highly significant differences were found among families in both F4 and F5 generations for two populations, except no. of spikes/plant in F4 generation in both populations, also biological yield/plant and grain yield/plant in F5 generation in population I, and also no. of spikes/plant in F5 generation in population II. Results showed that broad sense heritability estimates were low to moderately in F3 generation for both populations. Also, estimates of broad sense heritability (B.S.H) ranged from low to moderate /high for both F4 and F5 generations in two populations. Moderately differences were found between phenotypic and genotypic variability estimates (p.c.v.) and (g.c.v.) for all the three generations in both populations. Realized response to selection was found after two cycles of pedigree selection for 1000-grain weight in first population and grain yield/plant in the second population. In the first population after two cycles of the pedigree selection resulted one superiority family no. 16 which exceeded the best parent ,bulk sample and check variety by (18.12, 0.46 and 16.22 %) , (9.10, 3.26 and 28.19 %), (10.47, 29.97 and 2.70 %) and (11.88, 7.91 and 15.40 %), for no. of spikes / plant, biological yield , grain yield / plant and 1000-grain weight, respectively. In this regard, in the second population, the results revealed three families i.e. 21, 26 and 41 were attained the superiority for the studied traits. Concerning family no. 21 was exceeded by (30.51, 23.25 and 14.89%), (62.13 , 24.19 and 51.45 %), (14.43, 51.51 and 70.48 %) and (2.12, 15.31 and 23.29%) for no. of spikes / plant, biological yield , grain yield / plant and 1000-grain weight, respectively. Regarding, families no. 26 and 41 were exceeded by (37.34, 5.20 and 28.29 %) and (48.98, 14.40 and 39.16%), (38.72, 83.68 and 106.67 %) and (11.60, 47.76 and 66.26 %) and (12.46, 26.98 and 35.77 %) and (0.25, 13.20 and 21.03%) for biological yield, grain yield / plant and 1000-grain weight, respectively. [Abd-El-Haleem, S.H.M.; S.M.S. Mohamed and Ehab M.R. Metwali. Efficiency of Pedigree Selection in Bread Wheat under Drought Stress ConditionsII – Yield and its component traits. Life Sci J 2012; 9(4):3430-3437]. (ISSN: 1097-8135). http://www.lifesciencesite.com. 508