Use of Callus Cultures to Detect NaCl Tolerance in Cultivars of Three Species of Pasture Legumes

Abstract

The effect was examined of NaCl on the growth of callus from Medicago sativa L. cvv. Hunter River, Cuf 101, and Hasawi and line W75RS, and Trifolium repens L. cv. Ladino, all of which are regarded as salt-sensitive pasture legumes, and T. fragiferum L. cv. Palestine which is considered a moderately salt-tolerant pasture legume. Only M. sativa line W75RS showed some tolerance to NaCI, as callus growth was comparable at 0.1 and 62.5 mM NaCI. Whole plants in nutrient solution culture were grown from the same seed stocks and exposed to the same levels of NaCl as the callus. The responses were very similar to those shown by the callus cultures, with line W75RS showing some tolerance at 62.5 mM NaCI, which indicates the validity of using callus cultures to screen for tolerance to NaCl. However, on a yield basis, W75RS grew less than the other cultivars of M. sativa.