Response Of Solar Greenhouse Tomato To Drip Line Lay-outs And Irrigation Levels

People are giving more concerns on vegetable quality with the market prospering and living levels increasing recent years.Nowadays,abusing of irrigation water is extensive in greenhouse crop production,which leads to more plant diseases and insect pests,declining in vegetable quality and wasting of water and fertilizer.To investigate reasonable irrigation strategies and set up scientific irrigation management are very useful and meaningful for improving water and fertilizer use efficiency,guaranteeing vegetable quality and protecting environment.The experiments were carried out in a solar greenhouse of Yangling District,Shaanxi Province from 2015 to 2016.The tomato was chosen as experimental material.Two drip line layout were set up,i.e.one drip line provided irrigation for one plant row(G1)and one drip line provided irrigation for twin plant rows(G2).Under each of two drip line layouts,four irrigation levels were contained,i.e.K1(60% accumulative evaporation of 20 cm pan)、K2(80% accumulative evaporation of 20 cm pan)、K3(100% accumulative evaporation of 20 cm pan)、K4(120% accumulative evaporation of 20 cm pan).Through plot record,laboratory test and theoretical analysis,the response of tomato yield,quality and growth to the drip line lay-outs and irrigation levels was evaluated.The main conclusions follows:1.The height of tomato plant increased with the irrigation water;however,stem diameter and leaves area of tomato plant showed the same pattern that increased to the summit then followed decline with the increase of irrigation water.One drip line for single plant row treatmentsobtained higher plant height;however,one drip line for two plant rows showed more advantage to increase stem diameter and leaves area.2.For the plant dry matter accumulation,the spring-summer tomato plants were more heavier than winter-spring.The plant dry matter accumulation increased to the summit then followed decline with the increase of irrigation water.There were not significant difference between two drip line lay-out for plant dry matter accumulation.3.The yield of spring-summer tomato was much more than the yield of winter-spring,and the highest yield were responded to the moderate irrigation level.The yield increased with the irrigation to some extent then followed a decline when irrigation volume were too more.The lower tomato yield were attributable to less fruit number per plant and lower mean fruit weight.4.The irrigation water use efficiency of tomato plant decreased with the increasing of irrigation water;the irrigation water use efficiency of one drip line for two plant rows were higher than that of one drip line for one single plant row.5.The quality of tomato fruit of one drip line for two plant rows were higher than that of one drip line for one single plant row.Except for lycopene,the content of soluble solid,soluble sugar,organic acid and vitamin C were much higher in spring-summer.6.Taking all of yield,quality and irrigation water use efficiency into account,one drip line for two plant rows and moderate irrigation levels were recommended for tomato production in solar greenhouse in northwest China.