Effect of Salinity of Irrigation Water on Quality and Yield of Watermelon under Gravel Mulch
Brackish water irrigation is an effective measure to solve the shortage of water resources in arid areas.Appropriate salinity is an important index for the safe utilization of brackish water.Aiming at the effect of brackish water irrigation salinity on the growth,quality and yield of watermelon in the arid zone of central Ningxia,a field experiment with different salinity gradients was carried out.In order to explore the response mechanism of photosynthesis,yield and quality of watermelon to the salinity of brackish water,a comparative experiment of irrigation water salinity at 0.98,1.80,2.48,3.27,4.04,0.41,0.32 g/L was set up.The results showed that:(1)2.48 g/L salinity was the threshold of soil electrical conductivity change.The electrical conductivity of 20 cm soil depth under each treatment increased,and the soil conductivity under 4.04 g/L salinity brackish water irrigation increased the most,which was 78.7%higher than that of the Yellow River water(0.32 g/L)irrigation;(2)The daily water consumption of watermelon was inhibited to varying degrees when the salinity of irrigation water was>2.48 g/L from flowering and fruit setting stage to maturity stage.Compared with the Yellow River water irrigation,the daily water consumption of 4.04 g/L treatment decreased by 45.2%.(3)Brackish water irrigation can cause stomatal limitation,thereby affecting watermelon transpiration and inhibiting photosynthesis;(4)The yield of watermelon decreased significantly under brackish water irrigation.Compared with the Yellow River water irrigation,the yield of watermelon decreased by 20.5%under 4.04 g/L brackish water irrigation.(5)Brackish water irrigation can improve fruit quality.Under 2.48 g/L brackish water irrigation,the watermelon soluble solids content was the highest(13.05%);under 4.04 g/L brackish water irrigation,the watermelon vitamin C content was 8.3%higher than the Yellow River water irrigation.2.48 g/L brackish water is the threshold of brackish water irrigation in Xiangshan area.The research results can provide support and reference for the safe utilization of brackish water in the arid zone of central Ningxia.
国家科技期刊平台
NSTL
万方数据
