Growth, water relations and accumulation of organic and inorganic solutes in the halophyte Limonium latifolium cv. Avignon and its interspecific hybrid Limonium caspia X Limonium latifolium cv. Beltlaard during salt stress.

摘要

The effect of NaCl (140 mM for 20 days) on growth, water relations and nutrition in L. latifolium cv. Avignon and its interspecific hybrid L. caspia [L. caspium] X L. latifolium cv. Beltlaard, growing in hydroponics, was investigated. Shoot growth parameters of Beltlaard showed that plants were affected by salinity; salinity reduced shoot dry weight and leaf area compared with the control. Growth of Avignon was not influenced by salinity. Leaf water relations under saline stress were not differentbetween both genotypes, indicating that the osmotic effect was similar for both cultivars. At the end of the experiment the cultivars studied were able to achieve the same degree of osmotic adjustment. However, in Beltlaard the maintenance of turgor didnot permit the maintenance of growth rate. Reduced leaf growth in response to salinity was associated with higher tissue concentrations of Na+ and Cl-, and changes in the contribution of K+ and NO3- to leaf osmotic potential. The rates of NaCl absorptionby roots and the net transfer from roots to shoots were higher in Beltlaard than in Avignon, suggesting that radical exclusion mechanisms are more operative in Avignon.