Screening diverse wheat (Triticum aestivum L.) genotypes for spot blotch resistance
摘要
South Asian countries like India face various challenges for wheat (Triticum aestivum L.) production including spot blotch caused by Bipolaris sorokiniana resulting in grain yield loss of 25–43% depending upon the stage of infection. Evaluation of 50 genotypes for nine quantitative characters and area under disease progress curve (AUDPC) was estimated for identifying superior spot blotch tolerant genotype. Regression modelling using multiple linear regressions (MLR) predicted the most perceptive character influencing grain yield per plant and AUDPC. Days to 50% flowering registered maximum influence towards both grain yield per plant and AUDPC. Other important characters based on MLR were days to maturity, test weight, spike length and plant height. The genotypes could be assemblage into 10 clusters following D2 statistics suggesting presence of ample amount of divergence among the genotypes. Low AUDPC score and good yield performance were recorded for genotypes 29882, 29610, 29473, 29940, 29748, 29477 and 30081. Molecular validation confirmed that the genotypes that exhibited disease resistance under field condition possessed major resistance locus of either or both the quantitative trait loci (QTL) Sb1 and Sb3. High yielding and less susceptible genotypes to foliar blight disease identified in the present investigation provides an opportunity for wheat improvement and enhancement of wheat genetic resource through selective breeding.