Physiological Analysis of Tomato Genotype Under Peg Induced Drought Stress

Twenty genotypes of tomato were analyzed in an experiment to describe their resistant and susceptible capacity against drought stress. Artificial drought was created using different concentrations of PEG 6000. Physiological parameters such as germination percentage, shoot length, root length and dry weight of seedling biomass were taken two weeks after germination at seedling stage. Germination percentages are extremely affected by different PEG concentrations. Genotype EC-529083 showed higher level (39%) while VR-20 lower rate (14%) of germination percentage at 15% PEG concentration as compared to other genotypes. Root length was stimulated during initial impact of drought stress (5% PEG). Higher root length recorded in the three tomato genotypes H-86, SUPER BUG and NDT-3 (7.20, 7.13 and 6.8 cm respectively) at 15% PEG concentration. Seedling biomass decreased with increase in drought stress level in each variety with some variation. SUPERBUG, DWRT-2 and H-86 showed higher biomass (0.046, 0.039 and 0.037 g, respectively) under drought stress at 15% PEG concentration than other genotypes. EC-529083 showed higher tolerance level against drought stress by germinating with highest rate during extreme condition, and VR-20 showed highest susceptible level according to lower rate of germination percentage.