Response of upland cotton (Gossypium hirsutum L.) leaf chlorophyll content to high heat and low-soil water in the Arizona low desert

Abstract

The sustainable production of upland cotton, an economically important fiber crop, is threatened by changing environmental factors including high temperatures and low-soil water content. Both high heat and low-soil water can reduce net photosynthesis resulting in low fiber yields or poor fiber quality. Leaf chlorophyll content has a direct relationship with photosynthetic rate. Understanding how high heat and low-soil water affect chlorophyll content can identify opportunities for breeding improvement that will lead to sustainable fiber yields. A two-year field trial located in Maricopa Arizona measured leaf chlorophyll content, available soil water, ambient air temperatures, and cotton growth measurements collected by a high-clearance tractor equipped with proximal sensors. The results showed that low-soil water significantly increased leaf chlorophyll content, while high temperatures significantly reduced content. Structured equation modeling revealed that cotton may divert available resources to leaf area and chlorophyll content for the production of photosynthates during periods of high temperatures. Highlights• High heat and low-soil water have opposing effects on cotton leaf chlorophyll content • Structural equation modeling informs source/sink relationships in yield components • Irrigation management strategies can mitigate leaf chlorophyll degradation

Genetic Characterization and Performance Evaluation of Elite Cotton Strains for Morphological and Physio-Chemical Traits Under Heat Stress Conditions

“…The highest positive correlation was observed between net photosynthetic rate and total chlorophyll contents (r = 0.997**), while the highest negative correlation was seen between net photosynthetic rate and superoxide dismutase (r = -0.983**) (Table 4). Similar findings were reported by Majeed et al, 2024, Thompson et al, 2022and Lopez et al, 2003 who showed a significantly stronger association of morphological, physiological and biochemical traits with seed cotton yield and its quality under heat stress conditions. Therefore, these characters must be considered while selecting the parental material and subsequent generations to develop heat-tolerant, climatesmart cotton genotypes.…”

Straw Returning Measures Enhance Soil Moisture and Nutrients and Promote Cotton Growth

“…Insufficient chlorophyll content leads to reduced photosynthetic rates, hampering the generation of organic matter and energy output, ultimately negatively impacting crop yields. Moreover, dynamic changes in chlorophyll content also serve as an indicator of plant age, as crops with strong yields tend to possess long-lasting green leaves [51,52]. Previous studies have indicated that the application of appropriate straw mulch to wheat can significantly enhance its chlorophyll content and photosynthetic rate [53].…”

Unravelling Abiotic Stress Physiology in Cotton (Gossypium hirsutum L.): Biotechnological Interventions in Mitigating Abiotic Stress

“…The amalgamation of these findings offers a comprehensive perspective on how cotton plants effectively manage physiological disruptions triggered by salinity stress. Drawing on current research, it intricately outlines the response of plants to water scarcity, elucidating the adaptive mechanism of reduced stomatal conductance as a strategic effort to conserve water [87,88]. A noteworthy contribution of the chapter lies in its exploration of altered water potential under drought conditions.…”