Genotypic Variations in Tomato (Lycopersicon Esculentum Mill.) for Acquired Thermotolerance to Temperature Induction Response

摘要

Thirty genotypes of tomato (Lycopersicon esculentum Mill.) were evaluated for acquired thermotolerance in seedlings based on temperature induction response (TIR) technique. The study showed that all the genotypes exhibited better growth and survival after temperature induction treatment. Out of thirty on exposure to direct challenging temperature nineteen genotypes were found to be susceptible, five moderately tolerant, three tolerant and four dead whereas after induction five were found to be susceptible, eight were found to be moderately tolerant and seventeen genotypes found to be tolerant with better seedling survival percentages. Growth during recovery was also found to be increased in maximum number of genotypes under induction treatment. Genotype GT showed 25.3% of survival when exposed directly to challenging temperature whereas it showed 100% of survival after induction treatment. The GDR of genotype EC-520061 was found to be maximum (4.15 cm) but with lower survival percentage (27.6%) afterchallenging treatment. SDS-PAGE leaf protein profiling confirmed the presence of additional protein bands as a result of induction. Hence, TIR serves to be a better tool to identify tolerant and susceptible genotypes for acquired thermotolerance even atseedling stage.