Journal ID : AMA-16-11-2022-11816
[This article belongs to Volume - 53, Issue - 11]
Total View : 435

Title : Molecular identification of blast resistant genes in rice germplasm from the North-eastern region of India

Abstract :

Rice blast disease caused by the fungus Magnaporthe oryzae is one of the most devastating diseases causing huge losses worldwide. In the present study, 14 major blast resistance genes were investigated in rice genotypes originating from northeastern region of India. Based on phenotypic evaluation, 60 genotypes were classified into five distinct groups: resistant (1), moderately resistant (10), moderately susceptible (15), susceptible (21), and highly susceptible (13). The genetic frequencies of the 14 major blast resistance genes were between 11.66% and 100.00%, with only two genotypes possessing a maximum of 14 blast resistance genes. The cluster and population structure analysis grouped the landraces into three groups. Through principal coordinate analysis, the scatter plots partitioned the resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible genotypes into different groups. According to the PCoA analysis, the first two axes explained 19.12% and 16.18% of the total genetic variation, respectively, contributing a total of 35.31% of genetic variation. Similarly, model-based population structure analysis differentiated the landraces into three subpopulations, SP1, SP2, and SP3. Interestingly, the cluster analysis and population structures were associated respectively, such that The SG1 consisted of 28 genotypes, of which eleven (13.33%) were medium resistant. The SG2 comprised 18 genotypes, of which seven (37.55%) were medium susceptible. Similarly, SG3 included 14 genotypes with a high number of susceptible genotypes. The present study represents a valuable blast resistance genetic resource that could be used for identification of new R genes, and genomic studies donors for blast resistance.

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