Abstract
The irrigation water quality is not suitable for crop production in most regions of Iran. It is estimated that almost six BCM/year of saline water enter to the rivers, in Iran. The saline water can potentially use for growing of tolerant crops with a specific management on the agriculture practice. One of the management methods is the conjunction use of fresh and saline water. In this study, four conjunctive use of saline and fresh water is evaluated on yield and yield components of two sunflower cultivars. A split plot design was employed in completely randomize block form with eight treatments and four replication. The main level has two sunflower cultivars (Alestar and Haisan33) and in the sub main level, four irrigation regimes was exist (1- Irrigation with half saline water and then one half with fresh water, 2-Irrigation with half fresh water and then one more half with saline water, 3- Alternate irrigation with fresh and saline water 4-Conjunction irrigation). To prevent salt, the plots were irrigated with fresh water for the first three irrigation events. The treatments were applied up to the harvesting. The result shows that the saline- fresh irrigation regime had the highest yield index concerning oil, 100 seed's weight, seed yield, seed yield per capital, stem diameter, flower height, capital diameter, leaf area and leaf minerals. For Haisan33 cultivar the alternate regime and for the Alestar cultivar the conjunction regime was in the second grade.

Keywords: Saline water, Irrigation Management, Sunflower, Yield index