A Study of Physiological Characterization of Wheat (Triticum Aestivum L) Varieties

Physiological Characterization of wheat (Triticumaestivum L.) genotypes were characterized with respect to heat stress and spot blotch diseaseunder four environmental conditions viz. no stress (E1), stress due to spot blotch (E2), heat stress (E3) and combined stress (E4) alongwith molecular characterization using 28 SSR markers(associated with tolerance against heat stress and resistance against spot blotch disease). The experimental materials were evaluated in randomized block design (RBD) factorial. Observation on 1000-grain weight, grain filling duration (GFD), plant height, peduncle length, spike length, disease severity and area under disease progress curve (AUDPC) were recorded. Significant differences were observed among the genotypes for all the traits under consideration. Genotype × environment were found non-significant. The lowest performance of the genotypes under combined stress condition (E4) was recorded. The individual impact of heat stress with respect to performance of the genotype was found significantly higher than that caused by spot blotch disease. Raj 3765 for 1000-grain weight, WH 760 for GFD, Yangmai-6 for plant height, PBW 343 for peduncle length and HD 2733 for spike length, showed stable performance across the environment. On the basis of stress susceptibility index (SSI) the genotypes WH 760, DBW 14 and Raj 3765 were found better for the characters, 1000-grain weight and GFD. The overall disease severity was found maximum under heat stress condition. Similarly genotypes were having relatively more AUDPC under heat stress condition.