To identify salinity stress response and evaluate 15 Egyptian barley cultivars, two years field screening was carried out. During consecutive seasons 2015/2016 and 2016/2017 under two environments at Sakha farm (normal soil) and EL-Hamrowy farm as (saline soil). There were significant differences among all cultivars under study with respect to all traits. Moreover, the results revealed that the seed germination and seedling traits were decreased under salinity stress. Relative water content (RWC) significantly reduced under salinity stress for all cultivars. High proline content was recorded by Giza 136 (0.87 and 2.87mg/g) under control and salt stress respectively. Cultivars Giza 131, Giza 123 and Giza 136 had the best performance for grain yield under normal and salt conditions, and exhibited highly significant differences for all the salt tolerance indices. The SDS–PAGE revealed that the soluble protein accumulation increased in cultivars under control more that under salinity stress. 24 polymorphic bands were detected in all cultivars based on their gene expression in seedling under salinity and control with molecular weight ranging from 10 to 250 KDa. Seven SRAP combination primers were used to assess the genetic diversity among all cultivars. The primers showed high average percentage of polymorphic loci was 87.4 %. Highest PIC was related to primer me5+em5 was (0.94) indicating that this primer is highly informative. The dendrogram of SRAP markers had clustered all the Egyptian cultivars into four groups each group include the most closed cultivars together with genetic similarity coefficients (GSC) ranging from (0.64) to (0.92). The results of the present study showed that there were high genetic differences among Egyptian barley cultivars for salt tolerance which provide new information about the relationships among Egyptian barley cultivars which are useful for cultivar identification and for their utilization in further barley salt breeding programs |
