Abstract— The Temperature Induction Response (TIR) technique was standardized and employed to identify thermotolerant finger millet (Eleusine coracana L.) genotypes at the seedling stage. The technique involves exposing seedlings to a gradual sub-lethal temperature induction followed by a lethal temperature treatment, and subsequently assessing seedling recovery. Optimization of induction and lethal temperature regimes was based on percent seedling survival and percent reduction in root and shoot growth after a 72-h recovery period. An induction treatment ranging from 37°C to 52°C over five hours, followed by exposure to a lethal temperature of 58°C for two hours, was identified as optimal for screening. Fifteen finger millet genotypes were evaluated under induced and non-induced conditions. Genotypes were classified based on seedling survival percentage and growth reduction parameters. Cultivar Tirumala and genotype VR-1099 exhibited the least reduction in root and shoot growth along with higher survival rates, indicating superior thermotolerance. The study demonstrates that the TIR technique is an effective and rapid phenotyping tool for identifying thermotolerant finger millet genotypes at the seedling stage, facilitating the efficient selection of parental lines for breeding heat-resilient varieties.
Ramya et al. (2026) studied this question.