Evaluation of some Drought Adaptation Traits in Hordeum spontaneum L. Ecotypes from Different Climatic Conditions of Iran

Wild barley (Hordeum spontaneum) is a valuable source of genetic diversity for adaptation to biotic and abiotic stresses which can be used for transferation of new genes to cultivated barley. To evaluate wild barley ecotypes for drought adaptation، nineteen ecotypes and a barley cultivar (Nosrat) were evaluated in experimental field of Seed and Plant Improvement Institute in Karaj. The experiment was carried out in a randomized complete block design with three replications in non-stressed and water deficit stress conditions. Agronomical، phenological and morphological traits were measured in ecotypes. Results indicated that phonological traits such as days to spike emergence، days to flowering and days to maturity were decreased under water deficit stress condition. Agronomic traits including spike length، plant height and biological yield were also significantly decreased. Under normal condition، grain yield، biological yield and harvest index showed a significant correlation with stress tolerance index (STI). Principle component analysis in normal condition indicated that even in non-stresses condition، agronomic traits had correlation with stress tolerance. Cluster analysis grouped the ecotypes in three different clusters including susceptible، semi-tolerant and tolerant ecotypes. Based on the results، ecotypes no. 7، 8 and Nosrat cultivar had the highest yield components and stress tolerance index، however relative water loss (RWL) and days to maturity (DM) were less in these ecotypes (164 days and 74. 27%، respectively). The results of stepwise regression analysis indicated that the relative water loss is a physiological trait which shows a close relation with stress tolerance potential of the ecotypes and is an important factor for adaptations to water deficit conditions.