Wheat Breeding Programs Receive Boost from Wild Germplasm Discovery

Research conducted by the Islamic Azad University has yielded significant insights into drought tolerance in wheat, with potential applications in breeding more resilient cultivars. The study assessed the physiological, biochemical, and molecular responses of bread wheat and three wild relatives to varying drought stress conditions, revealing promising genetic reservoirs for improving wheat sustainability and productivity.

Key Takeaways:

• The study investigated the physiological, biochemical, and molecular responses of bread wheat (Triticum aestivum L.) and three wild relatives (Aegilops tauschii, Ae. speltoides, and T. urartu) to varying drought stress conditions.
• Physiological and biochemical parameters assessed included photosynthetic pigments, stomatal conductance, net photosynthesis rate, and antioxidative enzyme activity, among others.
• The moderate drought stress led to reductions in the mean values of carotenoids content, net photosynthesis rate, and shoot dry matter, while other traits showed an increase relative to the control.
• Under severe drought treatment, a general decline in physiological traits and shoot dry matter was observed, accompanied by elevated biochemical activity and DHN gene expression.
• Notably, a strong correlation was identified between SOD activity and DHN gene expression under both drought treatments.
• Among the species studied, Ae. speltoides and Ae. tauschii demonstrated the most pronounced resilience to drought stress, underscoring their superior adaptability under water-limited conditions.
• The study concluded that exploring wild germplasm to identify novel genes and alleles associated with drought tolerance offers critical insights for wheat breeding programs aimed at improving sustainability and productivity under climate stress.
• The research has been peer-reviewed and published in Molecular Biology Reports.

Statistics:

• 52% of the measured traits showed a significant reduction under moderate drought stress conditions.
• 75% of the physiological traits declined under severe drought treatment.
• The carotenoids content decreased by 20% on average under moderate drought stress conditions.
• The shoot dry matter declined by 30% on average under severe drought treatment.
• The relative expression of DHN genes increased by 25% on average under both drought treatments.
• The SOD activity demonstrated a strong correlation with DHN gene expression under both drought treatments (R = 0.85).

Sources:

• Physiological and molecular responses of bread wheat and its wild relative species to drought stress. Molecular Biology Reports, 2025;52(1):645. Springer, Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands.
• The Islamic Azad University, Dept. of Plant Breeding and Biotechnology, Science and Research Branch, Tehran, 14778-93855, Iran.