Inheritance of partial resistance to powdery mildew in spring wheat

Area of Science:

• Plant Breeding
• Genetics
• Agronomy

Background:

• Powdery mildew, caused by Erysiphe graminis f.sp. tritici, is a significant disease in spring wheat (Triticum aestivum L.).
• Understanding the genetic basis of resistance is crucial for developing resistant cultivars.

Purpose of the Study:

• To investigate the inheritance of partial resistance to powdery mildew in spring wheat.
• To estimate genetic parameters influencing resistance and evaluate selection strategies.

Main Methods:

• Generation means analyses were used to estimate genetic parameters from crosses between resistant and susceptible wheat cultivars.
• Selection effectiveness was assessed by evaluating F2-derived F4 progenies.

Main Results:

• Additive gene action was the primary genetic component for resistance across all crosses.
• Significant additive by additive and additive by dominance effects were observed in some crosses, while dominance effects were not significant.
• Selection in the F2 generation led to 21%–31% increases in resistance in subsequent generations.

Conclusions:

• Partial resistance to powdery mildew in these spring wheat cultivars is predominantly controlled by additive gene effects.
• Effective selection strategies can be employed in early generations to improve powdery mildew resistance in wheat breeding programs.