Assessment of Climate-resilient Cotton Genotypes Exhibiting High-temperature Tolerance

Abstract

Cotton is an important natural fiber worldwide. Abiotic factors such as high temperature stress reduce seed cotton production and fibre quality. The current research aims to screen cotton germplasm for high temperature tolerance. For this, 60 cotton genotypes were tested for two years with varying sowing dates. Split plot design was used to plant these genotypes after RCBD. The main plot sowing dates and sub-plot cotton genotypes were considered for both years. We recorded boll weight (BW), chlorophyll content (CC), cell membrane thermal stability (CMT), canopy temperature (CT), node number to first fruiting branch (NNFFB), and seed cotton yield (SCY). Heat-stress-tolerant cotton germplasm can be created by analyzing genetic variation, genotype-environment interaction, and characteristics associated with SCY. Studying the Genotype × Environment Interaction (GEI) of cotton genotypes for specified agro-physiological parameters using GGE biplot analysis. The genotypes FH Lalazar, MNH-1016, PB-76, MNH-992, and FH-458 are either stable or show positive interaction with high temperature stress conditions for most traits under study, suggesting they can be used in future breeding programs to develop heat stress-tolerant varieties. The correlation coefficients also showed that all traits except node number to first fruiting branch and canopy temperature were positively and significantly correlated with seed cotton yield under heat stress, suggesting that using one or more of these traits as selection criteria could increase cotton yield under heat stress.