Genetics and Breeding of Heat Tolerance in Rice

Abstract

Extreme weather events, especially heat waves, have become more frequent with global warming. High temperature significantly affects world food security by decreasing crop yield. Rice is intensively planted in tropical and subtropical areas in Asia, where high temperature has become a major factor affecting rice production. Rice is sensitive to high temperature, especially at booting and flowering stages. Rice varieties tolerant of high temperature are rare, and only a few heat-tolerant rice varieties have been identified. High temperature at booting and flowering stages causes sterile pollen, decreased pollen shedding, and poor pollen germination, which finally lead to a yield decrease. Heat-tolerant QTLs have been identified in different studies, but new breeding lines with considerable heat tolerance have not been bred using identified heat-tolerance donors and QTLs. Research on heat-tolerant donor identification, QTL mapping, gene cloning, and large-scale phenotyping technology is important for developing heat-tolerant rice varieties.

Effectiveness of heat tolerance rice cultivars in preserving grain appearance quality under high temperatures - A meta-analysis

“…The proposed models may potentially assist expert judgment by providing quantitative tolerance levels from multiple field data sets, although further testing of the model is needed for this purpose. Heat tolerance is required for other characteristics, particularly heat-induced spikelet sterility, which can substantially affect cereal yield (Ye et al,2021). However, because the growth processes and temperature sensitivity for spikelet sterility are different from those for grain quality in threshold values and sensitive stages (Sanchez et al,2014), modelling and enhancing heat tolerance for high-temperature-induced spikelet sterility requires different strategies that should be addressed separately from the present study.…”

Genetic Improvement of Heat Stress Tolerance in Cereal Crops

“…The rice flowering stage is the most sensitive period to high day or night temperatures [65]. Daily temperatures above 30 • C with daily maximum temperatures above 35 • C reduce yield by inhibiting seedling growth and tillering [66]. When high day temperature coincides with the reproductive stage (booting to anthesis), it results in lower pollen production, poor pollen development, and reduced anther dehiscence (pollen shedding), limiting the release of mature pollen, and spikelet fertility.…”

Unlocking the Potential of Rice for Thermotolerance using SSR Marker- Based Assessment of Genetic Variability and Population Structure

“…Rice (Oryza sativa L.) serves as the primary staple food for a substantial segment of the global population, with extensive cultivation and consumption, making up over 20% of the worldwide calorie intake (Ye et al, 2021). Notably, Asia accounts for approximately 90% of the total rice production, with India alone contributing 23% of this production (FAO, 2022).…”