Molecular marker-based validation of blast resistance gene Pi54 and identification of potential donors in temperate high altitude rice (Oryza sativa L.)

More than 100 genes have been reported to impart resistance against rice blast, however, not all are equally effective. Their effectiveness relies on factors such as the diversity in pathogen races prevailing in a certain area, rate of pathogen evolution, genetic background of a host and few others. Pi54 is a major gene showing resistance to Magnaporthe populations in North-west Himalayas. In search of novel temperate donors suitable to high altitudes, a set of germplasm was screened using gene based markers for Pi54. Eighty three exotic and indigenous germplasm lines were genotyped using gene based markers and also validated for disease reaction using Pi54 gene specific isolate namely, Mo-nwi-kash-32. Nine out of 83 germplasm lines amplified resistance specific alleles with both the markers Pi54 MAS and Pikh-STS. All these lines expressed resistance against the said diagnostic isolate, thereby validating the possible presence of gene in the lines. Further validation using more number of isolates and sequence analysis will help in mining useful alleles for this gene.