Temperature Induction Response: A Rapid Screening Technique for Thermotolerance in Plants

Global warming is a never-ending disastrous threat to the world and the existence of life. For many years, researchers have been cautioning about the disastrous results on the climate if the world touches average temperatures of 1.5ºC above the pre-industrial levels. High-temperature stress affects the growth and development of crops, Reduced photosynthesis and transpiration lead to lower biomass and increased respiration, leading to faster depletion of stored carbohydrates and reduced growth. Altered mineral nutrition and enzyme activity leads to nutrient imbalance and oxidative stress and eventually lowers yields to significant levels. Thermotolerance is a complex trait, and along with agronomic practices, there is a need for the identification and characterization of genotypes for heat tolerance, which is a prerequisite for crop improvement. Temperature Induction Response (TIR) is a high-throughput means successfully employed for assessing, identifying, and screening crop plants for thermotolerance in different crop species. TIR is based on the principle of the LD50 concept and acquired thermotolerance, which is crop-specific in nature. Hence, this review focuses on the relevance, methodology, standardization, mechanism, utilisation and significance of the TIR technique for crop improvement in different crop species to combat heat stress.