Oxygation Gives Yield And Soil Environment In Root-zoon Benefits To Tomato

Aerated irrigation is by means of subsurface drip irrigation(SDI) system with Venturi injectors. In this way, air and oxygen can continuously be supplied, in solution and as micro-bubbles, to root zone through the drip tape. Oxygation of the crop rhizosphere effected with SDI improves the performance and efficiency of the SDI system, making it potentially more attractive to growers. This should lead to an increase in adoption, and, therefore, contribute toward water saving for agriculture in the face of declining water allocation to the industry.Field experiment in greenhouse was conducted to investigate the potential of oxygation to enhance soil environment in rhizophere(soil respiration, soil oxygen content, soil water content), plant growth, yield and biomassof tomato. The experiments, comprised of O1(rhizosphere ventilation at seeding stage) 、O2(rhizosphere ventilation at flowing and fruit-setting stage)、O3(rhizosphere ventilation at fruit expansion stage) 、O4(rhizosphere ventilation at fruit mature stage) 、 O5/W1(rhizosphere ventilation at total stages or Kcp=1.0)、W2(Kcp=0.75) 、W3(Kcp=1.25)and control treatments, were randomized and replicated three times. A "Mazzei" venturi air- injector(Model 287) was installed in- line immediately following the pump. Results showed that aeration teratments can enhance soil environment, improve tomato yield and enhance tomato quality.(1)Compared with control, oxygation under different irrigation levels improved markedly soil respiration rate. Under W3、W1 and W2 treatments, soil respiration rates respectively increased 37.73%, 29.93%, 21.85%(2013) and 43.23%, 34.1%, 27.15%(2014). Aeration under different tomato growth stages, especially O2 and O5, also increased rate of soil respiration. Under oxygation soil oxygen content in root zone and soil temperature also increased and soil water content also decreased, because of oxygation, number of soil bacterial,fungi and actinomycetes incresed markedly.(2)Soil moisture is markedly related with soil temperature, soil temperature and soil moisture has evident correlation with soil respiration. From the correlativity of these factors of soil environment, we can know that the changes of soil moisture influence soil temperature and the changes of soil temperature and soil moisture influence soil respiration.(3)Due to oxygation, yield of per plant、weight of per fruit, aboveground biomass、harvest index and irrigation water use efficiency all sufficiently increased. Results also show that the quality of tomato were significantly increased, compared with control, in all oxygation treatments or especially aerated at late growth stages, lycopene, soluble suger, Vc and organic acids all markedly increased and nitrate content also significantly decreased.