Main content area

Polymorphism of microsatellite markers in barley varieties contrasting in response to drought stress

Drine, Sawsen, Guasmi, Ferdaous, Bacha, Hayet, Abdellaoui, Raoudha, Ferchichi, Ali
Revista brasileira de botânica 2017 v.40 no.2 pp. 463-473
Hordeum vulgare, barley, chromosomes, cultivars, drought, drought tolerance, genetic markers, genotype, leaves, malondialdehyde, microsatellite repeats, physiological response, plant growth, proline, water content, water stress, Jordan, Tunisia
Drought is one of the most serious abiotic stresses limiting plant growth and crop productivity worldwide. The long arm of the barley chromosome 4H is often implicated in adaptation to drought. Therefore, the aim of the present study was to explore the polymorphism of microsatellite markers localized mostly on chromosome 4H in eight barley varieties (Hordeum vulgare L.) representing the wide range of drought tolerance. The differences in physiological responses related to drought stress classified these genotypes in two groups based on the Euclidean distances. The susceptible varieties are gathered in the same cluster recording an average Euclidean distance of 27.2, and an average dissimilarity of approximately 52.4 regarding the drought-tolerant group. Tolerance to drought stress of the Tunisian and Jordanian barley cultivars was associated with lower changing ratios of malondialdehyde contents, smaller decrease in leaf water content and significant increase in proline concentration compared to other analyzed genotypes. In simple sequence repeat (SSR) analyses, from a total of 17 analyzed SSR primers, 12 microsatellites showed clear patterns with high level of polymorphism. Among the 12 polymorphic SSR primers, four were found to be polymorphic across drought susceptible and drought-tolerant cultivars (Bmag808, EBMAC624, WMS6 and BMAC0577). High level of diversity was observed in the chosen genotypes through analyzing both physiological traits and SSR markers. A significant correlation was observed between the distance matrices based on SSR markers and physiological data, as determined by the Pearson’s correlation coefficient (r = 0.63; Mantel test P < 0.05).