Divulging the variability of rice blast pathogen (Magnaporthe oryzae) population, in Telangana, India

The blast disease of rice is caused by a well-known pathogen Magnaporthe oryzae infecting the rice crop in all growth stages and results in devastating yield losses. Due to the complex polyphyletic lineage of the pathogen population and the existence of numerous transposable elements, understanding its genetic diversity is essential for effective disease management. The present study aims to minimize the rapid breakdown of disease resistance and in a way that limit the emergence of new races. Virulence screening on a set of rice differentials revealed the presence of 18 International races collected from various cultivars across three agroclimatic zones of Telangana, India. Further, 40 single spore isolates of M. oryzae were characterized using PCR-based genetic techniques such as RAPD, SSR, and Pot2-TIR. Notably, Lineage - I identified through Pot2 - TIR analysis contained the largest number of isolates, while other lineages represent smaller numbers of isolates. In broader terms, each lineage included isolates with different geographic origins, cultivars and diseased plant parts and there was no discernible relationship between pathotypes and DNA fingerprinting. Having been contemplated, these findings demonstrated that the M. oryzae population collected from various rice cultivars grown in Telangana had greater individual diversity than population diversity. Hence, for efficient disease management, use of certified seed and removal of collateral hosts are recommended.

The online version contains supplementary material available at 10.1007/s13205-025-04610-0.