Diallel Analysis for Estimation of Genetic Parameters in Relation to Traits of Wheat Height in Normal and Drought Conditions

In order to study inheritance of traits (Height, Peduncle length, Extrusion peduncle length, Diameter first internode, Diameter secondary internode, Diameter third internode length of secondary internode, length of third internode) associated with height in bread wheat, seven cultivars of bread wheat with their F1 progenies produced through a half diallel mating design were planted in a randomized complete block design with 3 replications in normal and drought conditions in the Seed and Plant Improvement Institute, Karaj, in 2004. Analysis of variance showed significant differences for all the traits in normal and drought conditions at 1 % probability level. Diallel analysis showed that general combining abilities were significant for all the traits in normal and drought conditions at 1% level of probability. The specific combining abilities were not significant except for extrusion peduncle length and length of secondary internode. Additive effect was more important in controlling all the traits. Height had the most broad sense and narrow sense heritabilities in normal and drought conditions. It was also found that increasing all the traits except for plant height and length of the third internode was controlled by the dominance alleles in normal and drought condition. The analysis of traits revealed more mean traits in progenies compared to parents in both normal and drought conditions. Sardary and Roshan varities showed the best general combining ability in normal and drought conditions.