Assessment of terminal heat tolerance ability of Indian mustard genotypes based on morpho-physiological traits

Abstract

Indian mustard (Brassica juncea) is a vital oilseed crop of the nation, contributing significantly to the agricultural 
economy. The growth of this crop, however, faces challenges due to changing climate conditions, particularly the 
increasing prevalence of heat stress during reproductive stages. This research was aimed to explore the impact of 
terminal heat stress on Indian mustard and to identify sources of terminal heat tolerance in Indian mustard germplasm for 
utilization in the breeding scheme. Therefore, a study on screening of Indian mustard genotypes against heat tolerance is 
conducted and total 200 Indian mustard genotypes were evaluated in augmented block design in two different sowing 
dates (14 November and 10 December 2021) at Rani Lakshmi Bai Central Agricultural University, Jhansi. Based on 
estimation of percent yield change, heat susceptibility index (HSI) and yield stability index (YSI) or heat tolerance index 
(HTI), nine genotypes viz. NDRE-4, EC-399300, DRMR-13, DRMR-9, DRMR-7, DRMR-357, DRMR-6, EC-766423 
and IM-76 were identified as promising accessions against heat tolerance. The study focuses on the agro-morphological 
traits influencing heat tolerance and proposes measures to ensure sustainable production under evolving climatic 
scenario.