Diversity and resistance analysis in wheat (Triticum aestivum) genotypes against spot blotch (Bipolaris sorokiniana) disease

摘要

Twenty wheat and triticale genotypes including indigenous and exotic were evaluated for three years (2007-08, 2008-09 and 2009-10) against different isolates i.e., BS 25, BS 34 and BS 75 of spot blotch disease causing pathogen (B. sorokiniana). Seedlings of the wheat genotypes showed different degrees of per cent disease index (PDI) with a range of 16.04 to 59.99. Maximum spot blotch severity was recorded on Lok Bharti (PDI 59.99) followed by genotype Agra Local (PDI 56.7). Four wheat genotypes, Shisenzhary 86 (PD118.49), Synthetic-23 (PD116.04), Chuanmai-18 (PD119.02) and BVE x Atila (PDI 19.20) showed moderate resistance whereas, one genotype, Chirya-3 was found moderately susceptible with PDI 29.83. URP profiles showed high level of polymorphism/genetic variability (90%) among wheat genotypes. The URP dendrogram illustrated one major cluster of susceptible wheat genotypes and one minor cluster of four moderately resistant wheat genotypes (Shisenzhary 86, Synthetic 23, Chuanmai 18 and BVE x Atila). Principal component analysis performed on URP data explained 70.41% variation among the wheat genotypes.