Pattern of accumulation of inorganic elements in sunflower (Helianthus annuus L.) plants subjected to salt stress and exogenous application of 5-aminolevulinic acid

Influence of a potential plant growth regulator,5-aminolevulinic acid (5-ala) on the pattern of accumulation of some key inorganic elements in salt-stressed sunflower plants was observed under greenhouse conditions. two cultivars of sunflower viz.,hysun-33 and s-278 were grown under non-saline and saline (150 mm nacl) regimes in sand culture. after two weeks of salt treatment,all plants were subjected to four (0 (no spray),20,50 and 80 mg l -1) levels of 5-ala as a foliar spray for 14 days. shoot fresh and dry matter of both sunflower cultivars was markedly reduced due to salt stress. of different inorganic ions,na + and cl - in leaf,stem and root tissues increased markedly while,k +,and ca 2+ in all these tissues reduced under the saline regime. however,salt stress did not alter the leaf,stem or root p as well as root k +/na + ratio. foliar-applied ala improved growth under normal (non-saline) and saline conditions,and 20 and 80 mg l -1 levels of 5-ala were relatively more effective than the other levels used in this study. of nutrient accumulation,5-ala altered only root na + and k + and root k +/na + ratio e.g.,root na + was lower at 50 mg l -1,while root k + and k +/na + ratio were higher at 80 mg l -1. in contrast,accumulation of all other ions in plant organs remained unaffected. overall,foliar-applied 5-ala did not alter the accumulation of different nutrients in different plant parts except root na +,k + and k +/na + ratio in both sunflower cultivars.