SALINE WATER APPLICATION AT VARIOUS GROWTH STAGES OF WHEAT: EFFECT ON IONS CONTENT

Abstract

Adverse effect of saline water on crops growth and yield may be associated to surplus amount of particular ion(s) and nutrient imbalances. Therefore, this pot study was carried out to quantify the effect of saline irrigation waters on ions concentration in sap and tissues of bread wheat (Triticum aestivum L. cv. Sarsabz). The crop was irrigated with saline waters (EC 2.0, 3.0, 4.0 and 5.0 dS m-1; prepared from NaCl and CaCl2 salts) at three growth stages, i.e. early growth stage (emergence and tillering), later growth stage (booting and grain formation) and all growth stages (emergence, tillering, booting and grain formation). Saline waters were applied at these growth stages either alone and/or in cycles with tap water (EC 0.6 dS m-1). Ions (Na+, K+ and Cl-) concentration was determined in the flag leaf sap, straw and grains of wheat. Results showed that the Na+ concentration in flag leaf sap, straw and grains was significantly increased as a function of saline waters (P < 0.05). There was a low concentration of K+ in flag leaf sap and wheat grains, and low K+/Na+ ratio in flag leaf sap, straw and grains. Saline water having EC 5.0 dS m-1 had more effect on Na+, K+ and K+/Na+ ratio than other treatments. Among various growth stages, the plants irrigated with saline water at later stages of growth had less Na+, more K+ and K+/Na+ ratio in sap, straw and grains of wheat, when compared with plants irrigated at all growth stages with saline water treatments. The findings of this study specify that the saline water having EC ? 5.0 dS m-1 may be applied at later growth stages (booting and grain formation) of wheat cultivar Sarsabz with a minimum risk of Na+ buildup in plant tissues.

Keywords

• ions content
• saline irrigation water
• wheat
• growth stages