Effects Of Water Saving And Nitrogen Reduction On Tomato Growth And Water And Nitrogen Use Efficiency In Solar Greenhouse

Water and fertilizer are the most important material in vegetable production as well as an important factor affecting the agricultural environment.However,unreasonable irrigation and fertilization is common in the production of the park,which not only results in water waste.The nitrate content in vegetable also increases with the increase of nitrogenous fertilizer application rate.In vegetable production,it is urgent to reduce the amount of water and nitrogen,the nitrate content of vegetables,the nitrate pollution of vegetable soil,groundwater and surface water.As a result,we can better achieve the goal of environmental friendly and resource-saving vegetable production.Also we will improve economic and social benefits.The experiment was carried out from April 2015 to July 2015 and from September 2016 to February 2017 in Xinyuan Sunshine Agriculture Park,Yongqing County,Langfang City,Hebei Province.The experiment took greenhouse tomato as the research object and adopted the comprehensive test design method.In this paper,the drip irrigation technology and the submembrane furrow irrigation technology were studied,irrigation amount(irrigation amount was divided into 3 levels: W3: experiential irrigation amount,W2: 80% of experience irrigation in the park,W1: 60% of experience irrigation in the park)and nitrogen application(nitrogen application amount divided into 3 levels: N3: experience rate of nitrogen application in the park,N2:50% of experience nitrogen application in the park,N1: no nitrogen)to the growth of tomato,the effects of yield,leakage and efficiency of water and nitrogen use can provide theoretical guidance and practical basis for efficient and high quality vegetable production.The main results are as follow:The amount of irrigation,the amount of nitrogen and the technique of irrigation had certain influence on the growth index of tomato.The high irrigation quantity was beneficial to the growth of tomato plant height,and the chlorophyll content of tomato leaves increased first and then decreased with the increase of irrigation amount.In the later stage of tomato growth,the chlorophyll content of high nitrogen application treatment was slightly higher than that of middle and low nitrogen application treatment,and the leaf area index increased first and then decreased with the increase of nitrogen application rate.Compared with W3 treatment,the water consumption of W2 and W1 treatments decreased by 17% and 43%,and the water use efficiency increased by 9% and 59%.Compared with N3 treatment,the tomato yield increased by 9% and 17%,and the productivity of nitrogen fertilizer increased by 12% and 35% compared with that of N3 and N1 treatment.The yield of tomato increased with the increase of irrigation amount,and increased first and then decreased with the increase of nitrogen application rate,which could be reduced appropriately in actual production.The soil leakage and total water consumption of tomato decreased with the decrease of irrigation.Compared with high irrigation and high nitrogen application,low irrigation and low nitrogen application reduced the leakage and total water consumption of tomato during growth period.Water use efficiency and partial productivity of nitrogen fertilizer increased with the decrease of irrigation amount and nitrogen application rate.From the point of view of surface soil moisture content,irrigation is carried out in spring and summer test when moisture content is between 21.3% and 22.4%,irrigation is carried out in autumn and winter test when moisture content is between 13.4% and 18.1%.Compared with W1 treatment,water content of W2 and W3 treatments increased by 0 ~ 16.4%,N1 and N2 treatments increased by 0 ~ 11.5% than that of N3 treatments.Compared with W3 treatment,treatment W1 and W2 increased the content of NO3-N by 0 ~ 23.1%,and the treatment of N2 and N3 increased 0.3%~16.3% than the treatment N1.The pH value of treatment W3 increased by 0~3.4% than that of treatment W1 and W2.The pH value of treatment N3 increased by 0 ~ 3.3% than that of treatment N1 and N2.The effect of irrigation on the soil moisture content of tomato was mainly concentrated in the soil layer of 0-40 cm depth.The nitrate nitrogen content in the soil decreased with the increase of soil depth,the soil moisture content and pH value decreased with the decrease of irrigation amount,and the soil salinity and electrical conductivity decreased with the increase of soil depth.Nitrate content increased with the decrease of irrigation amount,soil moisture content increased with the decrease of nitrogen application rate,and soil salinity,electrical conductivity,nitrate nitrogen content and pH value decreased with the decrease of nitrogen application rate.From the point of view of water saving and reducing nitrogen,80% of the experience irrigation amount,50% of the experience nitrogen amount will not significantly reduce the yield,but water and nitrogen use efficiency can be significantly improved;it can also reduce the amount of leakage and water consumption;from the point of irrigation technology,drip irrigation techniques are suggested to be used,the water consumption and leakage of tomato under drip irrigation technology are relatively small.Under drip irrigation,and tomato yield is higher than submembrane furrow irrigation.