Identification of heat tolerant barley genotypes based on heat susceptibility index

Abstract

The present experiment was planned to understand the impact of
high temperature on grain yield and its component traits in order to
select heat tolerant genotypes for future breeding programmes. Fifty
barley genotypes were evaluated under two environments created
by different dates of sowing i.e. timely sown and late sown, during
Rabi 2016-17. The mean sum of squares due to genotypes based on
heat susceptibility index (HSI) revealed the presence of significant
variation for all the traits except plant height, spike length and
grains per spike. Correlation among HSI of different traits indicated
significant positive association of grain yield per plot with harvest
index, biological yield, 1000-grain weight, plant height and days to
maturity. Out of 50 genotypes studied, HUB 242 exhibited lowest HSI
and percent reduction in grain yield under heat stress conditions. The
genotypes namely HUB 242, DWRUB 52, RD 2904, BH 902 and IBYTHI-
13 were found most promising based on heat susceptibility index
(HSI) of grain yield. However, based on overall rank of HSI of all the
traits, IBON-HI-13, IBYT-HI-13, RD 2904, HUB 242 and IBON-HI-3
were identified heat tolerant genotypes. These genotypes could be
utilized as promising breeding material for the development of new
heat tolerant barley varieties.