Rapid Screening of Tomato Varieties for Heavy Metal Stress Resistance Using Aseptic Seed Culture

Tomato (Solanum lycopersicum) considered an important vegetable throughout the world. It is also used as heavy metal tolerant crop. Local tomato varieties can perform better for Cr stress and remediate. Based on this hypothesis, the study was carried out to determine the tolerance and resistance of Cr. In vitro culture experiment was carried out on five Cr treatment 0, 0.25, 0.50, 0.75, and 1.00 mM/L along with three replications. Seed germination, mean germination time, shoot length, Fresh and Dry Shoot and root length, shoot and root tolerant index were examined. Results showed that, significant decreased was observed in seed germination percentage in response of Cr treatment compare with control. Whereas, the mean germination time of all cultivars increase as the treatment increases. Shoot height of all tomato cultivars significantly increases as Cr and the inhibition rate at the highest Cr concentration (1 mM) was more than 70%. However, the reducing in root length of all tomato cultivars were recorded. The sterile cultivation experiments exhibited a significant decrease in shoot and root fresh weight in response to Cr treatment quantities compared to the control, in which the highest Cr concentration (1 mM) having a significant impact on shoot and fresh weight. Similarly, the Shoot tolerant index (STI) was observed higher (87.0) at Purple Beauty, followed by Milky Yellow (85.1) a similar trend was also observed in Root tolerant index (RTI) of all the tomato cultivars at different Cr concentrations. It is concluded that as the Cr concentration increases some tomato cultivars performed better for the tolerant of and resistance.