Vol. 12, Issue 2 (2023)

Author(s):
Meghashri S Patil and JP Jaiswal

Abstract:
Wheat is third most important cereal crop grown worldwide and is staple source of diet for millions of people all over world. According to the sixth assessment report of the IPCC (2021), the temperature reaches the 1.5 °C warming limit, at least for some period of time in the middle of the 21st century. As a consequence of this, worldwide, wheat will be exposed to considerable variation in environmental conditions majorly heat stress which restricts wheat production and productivity during both germination as well as grain filling period. In the present investigation, the RILs population derived from crossing the two contrasting parents PBN51 and Raj 4014 were evaluated under late sown conditions (heat stress) at Pantnagar (2020-21) and were characterized for various morpho-physiological traits namely, days to 50% heading, Grain Filling Duration, relative chlorophyll content, Canopy Temperature Depression, plant height, days to maturity, TGW (Thousand Grain Weight) and grain yield per plot. The combined analysis of variance showed that the RILs differed significantly for the above recorded traits. The lines showed continuous variation with normal distribution and had negligible skewness and kurtosis. Broad sense heritability was found to be high for different morpho-physiological traits hence selection will be effective among these lines. Under heat stress, the lines 26, 32, 138, 189 and 15 were found to be top performing with higher grain yields. These lines can be used in further breeding programs for developing heat stress tolerance varieties in wheat.