Determination of the best indirect selection criteria in Iranian durum wheat (Triticum aestivum L.) genotypes under irrigated and drought stress conditions

In order to evaluate and classify morphological and morpho-physiological traits of durum wheat genotypes in drought and irrigated conditions 200 durum wheat genotypes were sown in modify augmented design with four replications during 2013- 2014 farming season. Two replications were considered as drought condition and two as irrigated. Factor analysis based on principal component analysis method and varimax rotation indicated that four important factors accounted for about 87 and 92 percent of the total variation among traits in drought and irrigated conditions, respectively. In drought stress condition, the first factor assigned 37 percent of total variation between traits and was significantly related with spike yield and it’s components. Therefore, this factor was regarded as spike seed yield factor. Other factors in drought stress condition accounted for 22, 16 and 12 percent of variation between traits and were entitled as plant seed yield, spike density and assimilate transmission factors, respectively. In irrigated condition, the first factor assigned 36 percent of total variation between traits and was significantly related with traits plant and spike seed yield, plant and spike harvest index, No. seed/spike and plant height. This factor was regarded as plant seed yield factor. Other factors in irrigated condition accounted for 24, 18 and 14 percent of variation between traits and were entitled as production, assimilate transmission and spike density factors, respectively. Overall, results revealed effect of different environments on extracted factors, percent of variation accounted for by factors and traits related with each factor.