Identification of slow rusting wheat genotypes against stripe rust pathotypes in India

Abstract

Stripe rust, caused by Puccinia striiformis f. sp. tritici poses a significant threat to wheat production globally. This study focused on evaluating the slow rusting resistance of wheat genotypes through various parameters, including Final Rust Severity (FRS), Coefficient of Disease Level (CDL), Area Under Disease Progress Curve (AUDPC), and the average infection rate (r). Field trials were conducted in India over two seasons, with susceptible checks, Agra Local, exhibiting 100% FRS, confirming effective inoculation. Several genotypes demonstrated varying levels of resistance, with eight lines. Moderately resistant and moderately susceptible responses were observed in other lines. AUDPC and CDL values were used to confirm slow rusting characteristics in certain genotypes, with lower values indicating better resistance. The study emphasizes the role of durable resistance genes, particularly those associated with MS or MR infection types, in developing slow-rusting varieties. These results highlight the importance of diverse germplasm and suggest potential strategies, such as gene pyramiding, to combat the emergence of new virulent pathotypes. This research contributes to the ongoing effort of identifying wheat lines with durable resistance, essential for the long-term management of stripe rust in wheat breeding programs.