Genetic analysis of stomatal conductance in upland cotton (Gossypium hirsutum L.) under contrasting temperature regimes

Abstract

Stomatal conductance plays an important role in the heat avoidance mechanism of crop plants. Stomatal conductance in cotton is genetically determined and has been shown to be associated with heat resistance and higher yields. Experiments were carried out with six generations (parental, F1, F2 and back crosses) of three upland cotton crosses under heat-stressed and non-stressed greenhouse and field regimes, to understand the inheritance pattern of stomatal conductance as affected by contrasting temperature regimes. The results revealed significant variation for stomatal conductance due to generations and generation×temperature regime interaction in the three crosses. In general, heat stress reduced stomatal conductance and available genetic variability. Temperature regimes exerted a significant effect on the expression of the genes responsible for stomatal conductance. High temperature or heat stress favoured the expression of genes having additive effects, while absence of heat stress favoured those having dominant effects in two of the three crosses evaluated. The third cross showed the opposite reaction. The results suggest that genes controlling stomatal conductance in the parents of the first two crosses (MNH-552, HR109-RT, CIM-448, CRIS-19) were different from those controlling stomatal conductance in FH-900 and N-Karishma, the parents of the third cross. The selection efficiency of stomatal conductance in segregating populations was likely to be affected by the complexity of its inheritance, environmental dependency, and presence of substantial non-allelic and genotype×temperature regime interactions.

Effect of different physiological traits on grain yield in barley grown under irrigated and terminal water deficit conditions

“…5). This high sensitivity of g s has also been reported in wheat (Ritchie et al 1990; Morgan & LeCain 1991) and cotton (Rahman 2005). Stomatal closure is the first response of plants to a lack of water, and the main limitation to photosynthesis provoked by such stress (Flexas & Medrano 2002).…”

Identification of heat-tolerant rice genotypes and their molecular characterisation using SSR markers

“…The genotypes Ptb-7, Ajay and Rajalakshmi have significantly reduced stomatal conductance under stress conditions indicating their susceptibility. Stomatal conductance has been reported to be genetically determined in cotton and has been strongly correlated to thermotolerance or heat avoidance mechanism (27).…”

Effects of Temperature and Light on Photosynthetic Heterosis of an Upland Cotton Hybrid Cultivar

“…The effects of the opening and closing of the stomata on the leaf temperature may be more important than those on the intracellular concentration of carbon dioxide at high temperatures. Stomatal conductance of cotton (Pima cotton and upland cotton) have been genetically determined and demonstrated to be associated with heat resistance and increased yields (Percy et al, 1996; Lu et al, 1994a, 1998; Lu and Zeiger, 1994b; Cornish et al, 1991; Rahman, 2005). The yields of the modern high‐yielding varieties of Pima cotton from the U.S. southwest desert areas have all benefited from leaf cooling, which was a direct result of the increased stomata control (Radin et al, 1994; Lu et al, 1997).…”