Genetic Variability, Correlation and Path Analyses for Yield and Yield Components of Some Bread Wheat Genotypes

Abstract

Two field experiments were carried out during 2014/2015 and 2015/2016 seasons under two sowing dates, 24 th November (optimum date) 25 th December (late date) at the Experimental Farm, Faculty of Agriculture, Zagazig University, Sharkia Governorate, Egypt using eight wheat genotypes to estimate genetic variability, phenotypic and genotypic correlations as well as path coefficient for yield and yield component characters. The results indicated significant differences among wheat genotypes for all the studied characters except chlorophyll content at the two seasons and number of spikes/m 2 at the 2 nd one only. Wheat genotypes Line 3, Sids 12 Misr 1, and Line 4 performed well under the late sowing date in the two seasons for yield and its component. Maximum phenotypic variance (Vp) and genotypic one (Vg) were recorded for number of spikes /m 2 under the two sowing dates and plant height under 2 nd one only. The (PCV) and (GCV) ranged from 27.69 and 26.08 % to 90.38 and 85.11% and from 20.26 and 12.66 % to 208.31 and 189.59 % for 1000 grain wheat and number of spikes/m 2 under 1 st sowing date and 2 nd one, respectively. The range observed for heritability (bs) was from (58.42) for number of fertile spikelets/spike to (95.3%) for number of grains /spike and from (39.04) for 1000 grain weight to (89.46%) for plant height under 1 st sowing date and 2 nd one, respectively. Spike length, number of fertile spikelets/spike, number of spikes /m 2 , number of grains /spike and 1000-grain weight were the most important traits which greatly correlated with grain yield at both genotypic and phenotypic levels. Maximum positive direct effect on grain yield was contributed mostly by 1000-grain weight (1.104), followed by number of grains/spike (0.626) and number of spikes/m 2 (0.352).This means that a slight increase in one of these traits may directly contribute to grain yield. Since these characters could be used as selection criteria for improving wheat grain yield.