Investigation of Glycine Betaine Application on Some Osmolytes Accumulation in Leaf and Root of Pistachio under Salt Stress

To study the effect of glycine betaine applicaion on accumulation of some osmolyte compounds in leaf and root of Qazvini Pistachio (Pistacia vera cv. Qazvini) under different salt stress levels¡ a greenhouse experiment was conducted based on completely randomized design (CRD) as factorial with two factors of salt stress (NaCl) at four levels (0¡ 50¡ 100 and 150 mM) and glycine betaine at three levels (0¡ 50 and 100 mM). Glycine betaine was applied at three stages: 1) 14 days after seed sowing at 4-leaf stage 2) 35 days after seed sowing 3) 55 days after seed sowing (10 days after stress commencement). Results showed that salt stress caused a reduction in total dry weight¡ leaf chlorophyll and carotenoids content and the less reduction was observed in seedlings sprayed with glycine betaine. Osmolytes concentration (soluble carbohydrates¡ proline and glycine betaine) were increased with increasing of salt stress level. Use of glycine betaine resulted in raising of internal content of it (leaf and root) and this raising was maximized under the highest level of salt (150 Mm) and glycine betaine (100 mM). Results of this experiment indicated the highest level of proline content¡ total soluble carbohydrates¡ sucrose and glycine betaine were observed when seedlings were exposed to 150 mM NaCl. Use of glycine betaine (especially at 100 mM) resulted in a lower content of proline¡ total soluble carbohydrates and sucrose in treated seedlings in comparison with non-treated seedlings. Proline was the most responsive osmolyte in leaf and roots in comparison with the others under salt stress condition.