A comparative study of salt tolerance in cultivated tomato and related wild species.

Salinity stress is a major abiotic stress for plants worldwide. This study was carried out to determine the variation in salt tolerance for 12 different genotypes belonging to three different tomato species: (L), (L) and (L). Shoot apices and callus cultures were exposed to different levels of salinity stress ranging from no salt (control) to 100, 200 and 300 mmol L NaCl. All growth and physiological parameters were significantly affected by salt stress. Most shoot apices of did not develop roots when exposed to low NaCl levels, whereas apices of and developed roots when exposed to all salt levels. This difference in salt tolerance was clearly shown on the basis of root fresh weights and root surface areas. Callus growth in response to increased salinity was much greater in and than in . The Cl and Na concentrations increased significantly with increasing salt in the three species, although the lines accumulated more ions compared with the others. As the salt concentration increased, less K accumulated in compared to the related wild species. The results obtained in this study suggest that line 0043-1 was the accession with the best salt tolerance. The most tolerant cultivated tomato () cultivar was 'Rutgers.' Both line 0043-1 and 'Rutgers' are good candidates for inclusion in tomato breeding programs for salt-tolerance.