Effects of Salinity and Boron Content of Irrigation Water on Growth and Micronutrient Concentrations of Purslane Plant

The effects of salinity and boron content of irrigation water on growth and micronutrient concentrations of purslane plant were studied. The growing population of the world and increasing demand for food has led to the unavoidable utilization of saline soils for crop production. Purslane is an annual herbaceous plant that grows well in saline soils. Boron (B) is an essential element for plants and may exist in toxic concentrations in saline soils, but the plants require it in small amount. To evaluate the effects of salinity and B levels of irrigation water on the yield and micronutrient concentrations of purslane plant, a factorial experiment with a completely randomized design in three replications and 35 treatments was conducted in greenhouse condition. The irrigation water had the salinity levels of 0.5, 2.5, 5.0, 10.0, 15.0, 20.0 and 25.0 dS/m and boron contents were 0, 0.5, 0, 1, 2, and 4 mg/liter. The results showed that the highest dry weight for aerial parts (1.29 gr) and root (0.24 gr) and the highest plant height (31.16 cm) and concentration of copper (29.1 mg. kg-1) in aerial parts were measured for the treatments irrigated by water with the salinity level of 0.5 dS/m and boron level of 0 mg/L. The highest concentration of iron (93.65 mg. kg-1) in aerial parts was measured for the plants irrigated by water with the salinity level of 10 dS/m and boron concentration of 0.5 mg/L. The highest concentration of zinc (64.26 mg. kg-1) in aerial parts was measured for the treatments irrigated by water with the salinity level of 2.5 dS/m and boron level of 2 mg/L. The highest concentration of manganese (98.26 mg. kg-1) in aerial parts was obtained from the treatments irrigated by water with the salinity level of 0.5 dS/m and boron level of 2 mg/L. In general, the results of this study indicate that for obtaining high yields of purslane plant, the salinity level of irrigation water should not be higher than 2.5 dS/m and the boron level should be less than 0.5 mg/L.