ISSRs profiles and protein patterns related to yield and yield compositions in several bread wheat genotypes growing under thermal stress

Six wheat cultivars (Triticum aestivum L.) from the Sudan collection were studied for their capacity to withstand thermal stress, depending on protein and ISSR markers profiling. Yield and yield components were determined under different sowing dates applied through a field experiment for season 14/2015. Both the DNA and protein patterns were profiled using inter-simple sequence repeats (ISSRs) and sodium dodecyl sulphate (SDS-PAGE) markers, respectively. The cultivars showed the same protein profile under the three treatments, indicating no association between the detected protein patterns (144 bands) and responses to different sowing dates. 415 fragments of DNA were generated by the six ISSR primers, of which 64.5 % were polymorphic. Values for polymorphism information content (PIC) were determined and ranged from 0.11 to 0.73. Three of the alleles that were detected for the Argine cultivar at late sowing may be considered candidates for heat stress tolerance. According to the findings of this study, cultivar Argine is the most heat-tolerant of the six cultivars studied and may be useful for wheat breeding strategies, whereas cultivar Condor may be grown in regions where the winter season is shorter or the sowing date is delayed. ISSR markers were found to be more efficient in estimating the variability within wheat cultivars compared with SDS-PAGE protein profiles.