Abstract: | Uptake and translocation of sodium in two cultivars of Lolium perenne The uptake and translocation of Na was investigated in two Lolium perenne cultivars (Dolewi and NFG). With increasing Na+ concentration in the nutrient solution (0, 1, 2 and 4 mMNa) the Na+ uptake per pot increased from 1.4 to 11.9 me/1 Na+ for Dolewi and from 1.1 to 6.9 me/l Na+ for NFG. The higher Na uptake by Dolewi can only partly be explained by better growth, the higher Na+ selectivity playing also an important role. In another experiment plants of both types were grown in solution cultures for 41/2 weeks at 15°C and 25°C, respectively. Hereafter the plants were supplied with 1.25 mM 24NaCl for six hours under equal conditions. Again the higher Na uptake and also a higher Na translocation (of about 20%) was found in Dolewi, whereas only 10% of the 24Na uptake had been translocated by NFG. When plants were grown in a nutrient solution with a lower temperature (at 15°C) the root lipids showed a higher linolenic acid and oleic acid content than the plants grown in a medium at 25°C. At the same time the 24Na uptake was higher in the plants grown at the lower temperature, yet the relationship between root lipids and Na uptake still remains to be elucidated. |