influence of Partial Root-zone Drying management with a combination of sea water on water productivity and sunflower yield

Application of saline water sources combined with reducing water consumption during crops growing seasons will have an important role in adjustment with water crisis. In this regard, applying a suitable water management aimed at sustaining crops under osmotic stress and water deficit can cause food security. Thus, in this research, the influence of partial root zone drying with a combination of sea water on quantitative properties and water productivity of sunflower was investigated in Agricultural Sciences and Natural Resources University of Sari. Treatments were arranged on factorial based on randomized complete block design with three replications. Six treatments included full irrigation with fresh water (FI), full irrigation with saline water (SI), full irrigation with periodic use of saline water and fresh water (FSI), partial root zone drying irrigation with fresh water (PRD1), partial root zone drying irrigation with saline water (PRD2) and partial root zone drying irrigation with periodic use of saline water and fresh water (PRD3). The results showed that significant difference was not found between the treatments of PRD1, PRD3 and FSI compared with FI in yield, harvest index and water productivity. The highest yield with the value of 4706 (kg/ha) in the control treatment and the maximum values of harvest index (%50.63) and water productivity (1.12 kg m3 ha-1) in PRD1 treatment was found. SI and PRD2 treatments had the lowest level of yield with values of 3983 and 3636 (kg/ha), respectively. It could be concluded that in addition to 25 % water saving under applying a suitable irrigation management in PRD3 treatment, it is possible to supply a part of crop water demand with saline water during treatment period which results in higher fresh water saving for sunflower cultivation.