biologia plantarum

Biologia plantarum 49:301-304, 2005 | DOI: 10.1007/s10535-005-1304-y

The effects of NaCl on growth, water relations, osmolytes and ion content in Kochia prostrata

G. Karimi^2,*, M. Ghorbanli¹, H. Heidari², R. A. Khavari Nejad¹, M. H. Assareh²

¹ Department of Biology, Tarbiat Moalem University, Tehran, Iran

² Department of Genetic and Physiology, Research Institute of Forest and Rangelands, Tehran, Iran

The effects of NaCl (0, 50, 100, 150 and 200 mM) on growth, water relations, glycinebetaine, free proline, ion contents, stomata number and size of Kochia prostrata (L.) Schard were determined. Shoot and root fresh and dry matter, root and shoot length, relative growth rate, net assimilation rate, relative water content, water use efficiency, soluble sugars and glycinebetaine contents were not changed at low NaCl concentrations, but they were significantly decreased at 200 mM NaCl. The K⁺, Mg²⁺ and Ca²⁺ contents, water potential, chlorophyll a+b and carotenoides contents, and stomata number and size were reduced already at low concentrations of NaCl. In contrast, the Na⁺, Cl^- and proline contents increased several times with increasing NaCl concentration. Kochia prostrata is a salt tolerant species, the optimal growth of this plant occurred up to 150 mM NaCl. The mechanisms of salt tolerance in the plant may be balance among ion accumulation and production of glycinebetaine, proline, soluble sugars for maintenance of pressure potential.

Keywords: glycinebetaine; halophyte; proline; stomata number and size; salt stress; salt tolerance; water use efficiency

Subjects: antioxidants, enzymes; carotenoids, antioxidant enzymes, salt stress; carotenoids, salt stress; chlorophylls, salt stress; glycinebetaine; growth analysis, plant development, biomass and yield enhancement; halophytes; Kochia prostrata; osmolytes; osmotic potential; oxidative stress, antioxidants; pressure potential; proline, salt stress; relative water content; salt stress, antioxidant enzymes; salt stress, osmolytes, ion contents; salt tolerance, osmolytes; stomata number and size, salt stress; sugars, soluble, salt stress; water potential; water relations; water use efficiency

Received: May 17, 2004; Accepted: September 24, 2004; Published: June 1, 2005Show citation