Effects of Salinity and Irrigation Water Management Strategies on Yield and Quality of Tomato in Subsurface Drip Irrigation

In this research, subsurface drip irrigation method by different salinities and its effects on soil, quality and yield parameters of tomato and also irrigation management methods including m1 and m2 have been compared. The m1 management strategy was alternative irrigation with fresh water and saline water, and m2 was saline water in first half of each irrigation event and fresh water in the second half. The experiment was conducted in 320 m2 area including 30 plots. Drippers were placed in 15 cm depth and in order to consider the interaction of salinity levels and management strategies a split plot design experiment with three replications was conducted in which management strategies (m1 and m2) were main plots and subplots were different levels of salinity including 0.68, 2, 4, 6, and 8 ds/m (s0, s1, s2, s3, s4, respectively). Results showed that tomato yield was decreased with increasing irrigation water salinity levels and the highest and lowest yields were in the m2S0 (52.44 ton/ha) and m1S4 (23.363 ton/ha) treatments, respectively. Also, average yield in m1 strategy was 17.77 % less than m2 strategy. In this research the other quantitative and qualitative parameters such as fruit density, fruit water content, texture strength, sodium, calcium and nitrogen concentrations and L , a and b colorimetric factors were measured. With increasing irrigation salinity, the sodium concentration in tomatoes was increased, but tomato water content and L factor were decreased. The variations of nitrogen, calcium, density, fruit number, fruit weight and “a” and “b” factors were nonsignificant. In general, m2 treatment was better than m1 treatment.