Combating leaf blight in wheat through resistance breeding

Abstract

Helminthosporium leaf blight (HLB) or spot blotch caused by Bipolaris sorokiniana is one of the most important diseases of wheat in hot and humid regions, resulting significant yield losses ranging 20- 50% percent especially under rice-wheat cropping system [1]. The disease severity of HLB has increased due to crop intensification, growing wheat in non-traditional areas. It has been considered a major production constraint affecting nearly 12 million ha area under wheat in South Asia's intensive cropping systems. Most of the wheat varieties released for commercial cultivation posses only moderate to low levels of resistance thereby pressing the immediate need to identify cultivars with high genetic resistance that could be utilized as potential donors in the future breeding programmes. It has also been emphasized that the identification of parental stocks possessing adequate level of resistance to B. sorokiniana is urgently required [2]. An effective control of HLB can be achieved by introducing resistant cultivars as a major component of integrated disease management. Therefore, the present investigation was aimed at screening and identification of the HLB resistant lines in wheat through field and poly house testing and their sharing for effective and strategic utilization in the breeding programmes.