Transcriptional Evaluation of Wheat Cultivars Under Drought and Salinity Stress: Identifying Potential Candidates for Stress-Resilient Breeding Programs

Abiotic stresses such as drought and salinity significantly impact global wheat (Triticum aestivum) production, especially in arid and semi-arid regions. Understanding transcriptional responses to these stresses is vital for identifying resilient cultivars and enhancing crop performance through breeding programs. This study evaluated the expression of two key transcription factors, TaERF3 and TabZIP1, across fourteen Egyptian wheat cultivars under varying levels of drought (5%, 15%, and 25% PEG 6000) and salinity stress (50, 150, and 250 mM NaCl) using qPCR. Expression profiles were visualized using a correlation based heatmap, clustering cultivars by correlation without data transformation. The results revealed distinct transcriptional clusters, with Beni Suef 7 forming a unique single-sample cluster due to its high TaERF3 expression under salinity and drought conditions, making it a prime candidate for breeding programs. A second cluster grouped Gimmeza 12, Sakha 93, Misr 2, Misr 1, Sids 14, Sids 1, and Sohag 5, which showed balanced expression of both transcription factors, suggesting shared mechanisms of stress adaptation. Misr 3, Giza 186, and Sohag 4 formed a third cluster characterized by strong TabZIP1 expression under drought stress. Shandawel 1, Sakha 95, and Sids 12 clustered together, exhibiting the lowest transcriptional responses. This study highlights the diversity of transcriptional strategies among wheat cultivars, with Beni Suef 7 and Giza 186 emerging as key candidates for drought and salinity resilience. These findings provide valuable molecular insights for breeding programs targeting stress-tolerant wheat varieties, particularly for challenging environments such as Saudi Arabia.