Comparative salt responses at cell and whole-plant levels of cultivated and wild tomato species and their hybrid

SUMMARY

Response to increased salinity was compared in whole plants and calli from leaf, stem and root of Lycopersicon esculentum Mill. cv. P-73, Lycopersicon pennellii (Correll) D'Arcy ac PE-47 and their interspecific hybrid. Three NaCl treatments were applied (0, 70 and 140 raM) for 28 d. In both calli and whole plants, L. pennellii was more salt-tolerant than the cultivated species and the hybrid according to the growth responses, although different degrees of salt tolerance were generally found between plants and calli. The Na⁺ and CI" accumulations with salinity were higher in L. pennellii than in L. esculentum at both levels oforganization. The interspecific hybrid showed an accumulation ability for Na⁺ and CI^" intermediate to its parents in the shoot of the whole plants and similar to L. pennellii in the callus tissues. Either no decrease or a small decrease of K⁺ concentrations with salinity were found in both whole plants and callus tissues of L. esculentum. However, K⁺ concentrations decreased in the organs and calli of L. pennellii and the hybrid with increasing salinity. Only at the whole plant level did L. pennellii have a Na7K⁺ ratio higher than L. esculentum, showing the hybrid to have values between those of its parents in the shoot.