SALINITY INDUCED DIFFERENCES IN GROWTH AND NUTRIENT ACCUMULATION IN FIVE BARLEY CULTIVARS

Abstract

Salinity-induced changes in growth, photosynthetic performance and nutrient accumulation were determined in five barley (Hordeum vulgare L.) cultivars, subjected to different NaCl concentrations (120 and 240 mM) under controlled conditions. According to germination test data, two of these cultivars (Suleyman Bey and Vamik Hoca) were evaluated as more tolerant while Anadolu 98, Efes 3 and Gem cultivars were assessed as less tolerant. In the early growth stage (one-week-old seedlings) salinity caused an increase of the root/coleoptile length ratio in the less tolerant cultivars while it was not changed in the more tolerant ones. In 4-week-old plants, PSII activity, chlorophyll a and chlorophyll b were not affected negatively by NaCl stress, the carotenoids being even increased. Na+ and Cl- accumulation in all genotypes were raised by NaCl salinity and the shoots accumulated ions at least 4-fold more than the roots. The K+ /Na+ and Ca2+/Na+ ratio and Mg accumulation in the shoots of more tolerant Suleyman Bey and Vamik Hoca cultivars remained almost constant with control level. The study established that evolved salt tolerance strategy among the barley cultivars was based on maintenance of more cationic nutrients in shoots (K, Ca and Mg) and protection of photosynthetic apparatus in saline conditions.