Screening and biochemical responses of tomato (Lycopersicum esculentum L.) genotypes for salt tolerance

Tomato ( Lycopersicum esculentum ), is an important nutrition rich vegetable crops generally displays sensitivity to different levels of salinity. In this work, twenty-one tomato accessions were hydroponically tested under controlled environmental condition for salt tolerance using 0, 8 and 12 dS/m salinity at seedling stage. All the plants were died after 6 days at 12 dS/m and data were collected for plants grown in control and 8 dS/m salinity condition. A significant difference was observed for genotypes, treatment and treatment-genotype interaction for both morphological and biochemical traits studied. Genotype T8 and BINA tomato 10 were performed relatively well under stress condition in terms of root/shoot length and weight, chlorophyll content, % live leaves and leaf area. TC0130-41-52-3-56-0-0 and Joint hybrid were considered as more vulnerable accessions. Average leaf injury score was also low in T8 and BINA tomato 10. Biochemical analyses using the selected genotypes shows, the tolerant accession has lower Na + content and also low Na + /K + ratio, higher ascorbate peroxidase (APX) and catalase (CAT) activity, high content of hydrogen peroxide (H 2 O 2 ), osmoprotectant; proline and ascorbic acid (AsA) compared to sensitive genotypes upon exposure to salinity stress, which might play a vital role in cellular protection during stress. Correlation study revealed the significant positive relationships among the studied biochemical traits and in principal component analysis, all the studied traits were subjected to one major component covering about 74.2% of total distinction. The results provide sources of potential genetic resources which can be further investigated to develop morphological and biochemical markers.