اثرات مستقیم و غیرمستقیم صفات زراعی بر عملکرد دانه گندم تحت شرایط دیم

In order to determine direct and indirect effects of some traits on grain yield of wheat under rainfed conditions, a square lattice experimental design (8×8) with 64 advanced lines along with four controls in two replications was conducted in the research farm of faculty of agriculture, university of Zanjan, in 2012-2013. Agronomic traits: biomass, harvest index, number of grains per spike, number spike and 1000-grain weight. To eliminating the noneffective or less effective traits on the grain yield, stepwise regression analysis was used and then path analysis was used to analysis the correlation coefficients of grain yield with effective traits to direct and indirect effects. Results of path analysis showed that direct effects of number of grains per spike, number spike, 1000-grain weight, biomass and harvest index were positive and significant. Path analysis indicated that the biomass yield the most direct effect is positive.