High day and night temperatures impact on cotton yield and quality—current status and future research direction

Abstract Heat waves, and an increased number of warm days and nights, have become more prevalent in major agricultural regions of the world. Although well adapted to semi-arid regions, cotton is vulnerable to high temperatures, particularly during flowering and boll development. To maintain lint yield potential without compromising its quality under high-temperature stress, it is essential to understand the effects of heat stress on various stages of plant growth and development, and associated tolerance mechanisms. Despite ongoing efforts to gather data on the effects of heat stress on cotton growth and development, there remains a critical gap in understanding the distinct influence of high temperatures during the day and night on cotton yield and quality. Also, identifying mechanisms and target traits that induce greater high day and night temperature tolerance is essential for breeding climate-resilient cotton for future uncertain climates. To bridge these knowledge gaps, we embarked on a rigorous and comprehensive review of published literature, delving into the impact of heat stress on cotton yields and the consequential losses in fiber quality. This review encompasses information on the effects of heat stress on growth, physiological, and biochemical responses, fertilization, cotton yield, and quality. Additionally, we discuss management options for minimizing heat stress-induced damage, and the benefits of integrating conventional and genomics-assisted breeding for developing heat-tolerant cotton cultivars. Finally, future research areas that need to be addressed to develop heat-resilient cotton are proposed.