Path analysis of grain yield with ıts components in durum wheat under drought stress

Abstract

This experiment was conducted in order to study the path analysis of grain yield with its components in durum wheat under potential and drought stress condition during 2005-2006 cropping season in Agriculture Research Station of Tabriz Islamic Azad University. 49 durum wheat line (6 line from Iran and 43line from other fount) was used for this purpose. Two separate simple lattic design (7 7) with two replications was conducted . In one experiment, the plants were commonly irrigated until physiological but in another experiment drought stress imposed in four different stages including; tillering, stem elongation, anthesis and grain filling. Correlations among traits after combining two experiments was calculated by SPSS software . Harvest index(r =0.849**), plant height(r =0.695**), and number of tiller (r =0.689**) had high correlation with grain yield. Back ward regressions was used for regressing grain yield on its components. Number of seeds per spike (0.432) , length of spike(0.407) and 1000 seed weight (0.385) had the highest direct positive effects on grain yield. Path analysis for 1000 seed weight, number of tillers per plant and number of seeds per spike showed that plant height (0.452), length of spike (0.857), days to flowering (0.345) were the most effective components of traits, respectively. Therefore, traits such as number of seeds per spike, spike length and 1000 seed weight could be used as a suitable indices in irrigated and dry farming conditions for obtaining durum wheat genotypes with high yield.