Environmental interaction, additive and non-additive genetic variability is involved in the expression of tissue and whole-plant heat tolerance in upland cotton (Gossypium hirsutum. L)

Abstract

Heat tolerance is measured at tissue level by cellular membrane thermostability (CMT) and at the whole plant level by the heat tolerance index (HTI). Eight upland cotton cultivars and 15 crosses were used to determine the type and extent of genetic variability associated with the expression of these traits between and within environments. Heat stress and non-stress conditions were used as the CMT environments and years for HTI. The wide variation in heterotic expression and combining ability effects observed for CMT and HTI suggest multigenic inheritance of these traits. Significant genetic variability across environments was evident but the traits were not highly heritable because of substantial environmental interaction. The available genetic variability included both additive and non-additive components, but the proportion of additive genetic variability was high for HTI. The parental cultivars CRIS-19 and CIM-448 were good donor parents for high CMT under heat-stressed conditions, and MNH-552 and N-Karishma under non-stressed conditions. Cultivar FH-634 was a good donor parent for HTI. The results show two types of general combining ability (GCA) inheritance among high CMT parents: positive GCA inheritance expressed by CRIS-19 in the presence of heat stress and MNH-552 and N-Karishma in the absence of heat stress; and negative GCA inheritance expressed by FH-900 in the presence of heat stress. It was also evident that genes controlling high CMT in cultivar CRIS-19 were different from those present in the MNH-552, N-Karishma and FH-900 cultivars. Similarly, among high HTI parents, FH-634 showed positive and CIM-443 negative GCA inheritance. No significant relationship due to genetic causes existed between tissue and whole plant heat tolerance, diminishing the likelihood of simultaneous improvement and selection of the two traits.

Identification of Heat Tolerant Cotton Lines Showing Genetic Variation in Cell Membrane Thermostability, Stomata, and Trichome Size and Its Effect on Yield and Fiber Quality Traits

“…Results indicated the values of HSI < 1 for heat-tolerant genotypes. Previously, Hafeez-ur-Rahman (2006) measures the heat tolerance in cotton at the whole-plant level using the heat-tolerant index. The SEM study of heat-tolerant genotypes along with susceptible check revealed a wide range of stomata and trichome size present on leaves of these genotypes.…”

Interactive Effects of Salinity, Drought, and Heat Stresses on Physiological Process and Selection Criteria for Breeding Stress-Resistant Cotton

“…In quantitative genetic studies about heritability and gene action for different selection criteria of heat stress, multigenic inheritance and both additive and nonadditive gene action in controlling cellular membrane thermostability was found to be higher under heat stress conditions [140]. The results of the scaling test, which is an important biometrical analysis method, indicated the significant dominance, additive x dominance, and dominance x dominance referred to as non-additive gene action for relative cell injury under heat stress [141].…”