Path analysis of effective traits on oil and protein yield in sesame genotypes under different moisture conditions and mycorrhiza utilization

To determine the traits affecting oil and protein yield and selection of suitable sesame cultivars under inoculum conditions and lack of inoculation with mycorhizal fungi and different levels of irrigation, an experiment was conducted as factorial-split plot design with three replications in research farm of Agricultural Research Center (Saatloo station of Urmia) during 2015 -2016 cropping seasons. The main plots consisted of factor A: three different levels of irrigations (normal irrigation: irrigation after 70 mm evaporation of crop or ETc, moderate drought stress: irrigation after 90 mm ETc and severe drought stress: irrigation after 110 mm ETc) and factor B: three levels of inoculation: two kinds of mycorrhizal fungi Glomus mosseae, Glomus intraradices and non-inoculated (control). Sub plots (factor C) consisted of eight commercial cultivars of sesame. In stepwise regression analysis, regarding oil and protein yield as response variables, in addition to grain yield and oil percentage and protein percentage, different traits were introduced under different conditions of mycorrhiza and water stress conditions. In path analysis (traits entered on the model included seed yield, oil percentage, seeds per square, protein percentage, capsules per plant, seeds per capsule, biological yield, protein yield, 1000-seed weight, oil yield, number of branches, plant height, stem diameter and root colonization) under different experimental conditions, the highest direct effect on oil and protein yield was obtained from oil percentage and protein percentage, respectively. Based on cluster analysis results, the "Darab 2" and "Darab 14" cultivars are suitable for cultivation in different conditions. Also, it sems that seed yield and oil percentage traits to achieve high oil yield and seed yield and protein percentage traits as selective indices to achieve high protein yield suitable.