Intraspecific Variation for Salt Tolerance in White Clover

Variation in the salt tolerance of 10 commercial cultivars of white clover (Trifolium repens L.) was evaluated in greenhouse and field· experiments over a range of NaCl concentrations. Cultivars differed significantly in terms of yield, shoot ion concentrations and parameters of growth such as leaf expansion and petiole elongation rates but not in the root concentrations of Cl or Na. The ability to control the entry and distribution of Cl and Na into the shoot (demonstrated by tolerant cultivars Haifa and irrigation compared with sensitive cultivars Ladino and Tamar) was related to the salt tolerance rankings observed in both the field and greenhouse experiments. It is shown that cultivars with superior salt tolerance can be selected to maximize pasture growth under saline conditions and that further studies on the physiological basis for salt tolerance in T. repens can be pursued ..