Phenotypic Screening of Heat-Tolerant Wheat (TriticumAestivum L.) Genotypes

Abstract

Ten Bread Wheat (Triticumaestivum L.) genotypes developed through different breeding techniques (BWM-3, MSH-36, MASR-03, MASR09, MASR07, NIA-10/8, NIA-28/4, DH-25) were evaluated for terminal high temperature stress for yield and yield associated traits. Sarsabz and T.D-1 were used as check varieties. The heat stress was imposed by planting on three different sowing dates. Early sowing (8th November) was used as control. Experiment was conducted in Randomized Complete Block Design (RCBD) with three replications. The results showed the inhibitory effect of high temperature on most of the yield and yield associated traits. Spike length, grain yield and biological yield were the severely affected traits. 10.3% reduction was found for mean spike length at late sowing (SD-3) and 11.0 % at Normal sowing (SD-2) as compared to early sowing (SD1). Mean spike yield reduced 3.05% at normal sowing to 2.17% at late sowing. 1000 grain weight decreased 40.63% at normal sowing to 37.3% at late sowing. Grains per plant declined 52.2% at normal sowing to 45.2% at late sowing. Grains per plot also reduced 798.3 at normal sowing to 641.3 at late sowing. Over all five genotypes Viz; BWM-3, MSH-36, MASR-09, NIA 10/8 and TD-1 performed better under late sown conditions for grain yield and yield associated traits. These genotypes may further be used in breeding program for developing heat tolerant varieties