Assessment of wheat genotypes based on genotype-by-environment interaction for durable resistance to spot blotch disease in hot spot

Abstract

Spot blotch, an important foliar fungal disease caused by Bipolaris sorokiniana (Sacc.) Shoemaker [stat. anam.], is the influential production restraint over the global wheat-growing regions. A set of eight diverse wheat genotypes including a few breeding lines from Uttar Banga Krishi Viswavidyalaya and commonly accepted susceptible cultivars were screened for spot blotch disease and grain yield across five different locations in West Bengal, India, under environments for natural disease infestation in post-rainy seasons of 2018–2019 and 2019–2020. The present investigation revealed significant variation among the genotypes for spot blotch resistance in different environments as a result of genotype main effect and genotype environment interaction. This study also recorded two genotypes as resistant against spot blotch disease over the five locations. Identified resistant genotypes increased grain yield as a consequence of resistance offered against spot blotch disease suggesting the possibility of considering disease resistance as a must-have trait in all the wheat cultivars that could be identified for cultivation in the North-Eastern Plain Zone of India. Two genotypes resistant to spot blotch recorded 1.26–1.46 times higher grain yield over control under disease pressure that can be recommended for identification and exploited in a resistance breeding program for wheat spot blotch disease-prone region.