Selection for drought tolerant barley (Hordeum vulgareL.) genotypes under climatic conditions of Karaj, Iran

Abstract

Field experiment was carried out in 2010 to evaluate the response of different genotypes of barley (Hordeum vulgare) to drought stress at the Agricultural Faculty of Azad University of Karaj, Iran. The experimental design was a randomized complete block with a split-plot arrangement and four replications. Treatments were two levels of irrigation (normal and deficit irrigation) as main plots and barley varieties at 10 levels (Valfajr, Rayhan, Kavir, Zarjo, Goharjo, Karoon, Dasht, Turkmen, Nosrat and Yousef) as sub-plots. A correlation was found between grain yield with spike weight, harvest index, biomass, peduncle length and number of spikes per unit area (at the 0.01 level) under drought stress. Data analysis also revealed that there was a significant and positive correlation between grain yield with spike weight, harvest index, biomass, number of spikes per unit area and total dry weight (at the 0.01 level) under normal stress (at the 0.01 level). Five selection indices including mean productivity index (MP), geometric mean productivity (GMP), stress tolerance index (STI), stress susceptibility index (SSI) and tolerance (TOL) were determined based on grain yield under drought-stress and non-stress conditions. The results showed that MP, GMP and STI were the best indices in identifying high yielding cultivars in both drought-stressed and normal conditions. Genotypes Nosrat, Turkmen and Youseph were the most drought tolerant and Kavir, Karoon and Zarjo were the most sensitive genotypes to drought stress.