Variation of Agronomic Traits in Durum Wheat Genotypes

Sixty durum wheat genotypes selected from previous evaluation of National Plant Gene Bank of Iran and Cereal Department Collection, comprises of local durum wheat and some cultivars from other countries, were studied. The genotypes were evaluated along with nine durum checks for agronomic traits in an Augmented design experiment during 2009-2010 cropping season at Seed and Plant Improvement Institute, Karaj, Iran. Each genotype was planted in six rows of 3m long. The checks were repeated four times among the rows, randomly. The recorded traits were adjusted based on the model of the design. Descriptive analysis of data showed presence of a vast genetic variability among the genotypes for the recorded traits. Correlation analysis among the traits revealed positive correlation between grain yield and grain number per spike (r = 0.32**), and grain weight per spike(r = 0.38**), whereas its correlation with plant height (r = -0.53**) and length of peduncle(r = -0.42**) was negative. By stepwise regression analysis plant height and date to heading remained in the final model. Factor analysis using principal components, identified 3 factors which covered 67% of total variation in the samples. Plant height, and yield components were present in the factors. Cluster analysis using Ward method grouped the genotypes in six clusters. Fifteen genotypes out yielded the mean of all checks, however only four were superior to the highest yielding checks, i.e. genotypes Nos. 3 (Wc-46198, with 9789 kgha-1), 11(Wc-46031, a Japanese variety with 9927 kgha-1), 10 (Wc-46043, a Japanese variety with 10066 kgha-1), and 55 (P.S.No22, with 10273 kgha-1) which were considered as the best and selected for further evaluations.