Effect of drought stress on some morphological and physiological traits in Aegilops tauschii genotypes

Abstract

Aegilops tauschii is one of the ancestors of bread wheat and is the main source of genes for resistance to biotic and abiotic stresses. The present research was performed as a factorial experiment based on a completely randomized design to determine the effect of drought stress on some morphological traits in 23 A. tauschii genotypes. The some important morphological and physiological traits were evaluated in greenhouse conditions at Imam Khomeini International University. The results showed the root length, the number of leaves and tillers, chlorophyll concentration, shoot and root fresh weight, shoot and root dry weight, percentage of yellow and rolled leaves at seedling stage and shoot and root dry weight, flag leaf, peduncle and spike length and the number of spikes at maturity stage were increased in drought stress. In the seedling stage, the highest root length, number of leaves, root fresh and dry weight, percentage of yellow and rolled leaves were 44.67 cm, 24.00, 3.35 g/plant, 0.40 g/plant, 50.00% and 80.79% under drought condition, respectively. In the maturity stage, the highest amount of shoot and root dry weights were 26.58 and 41.77 g/plant obtained in genotypes 55 and 2122 under drought condition and the highest value of flag leaf length, peduncle length, spike length and the number of spike were 12.30 cm, 15.65 cm, 9.08 cm and 30.00 observed in genotypes 2123, 2225 and 621 at control, respectively. The results of this study showed genotypes 621, 1772 and 2225 can tolerate drought stress well and therefore recommended for use in wheat breeding programs