Research Of Effects Of Water,fertilizer,gas And Heat Coupling On Growth Mechanism And Yield Of Tomato In Greenhouse

Against the actual problems such as low utilization efficiency of irrigation water and fertilizer of vegetable crops grown in greenhouses which are built in non-cultivated land located in Helan county,Ningxia,based on the greenhouse vegetable test demonstration base in Xinrong village of Helan,the paper adopts both the orthogonal test and the quadratic regression general rotation combination test method,researches coupling effects of water,fertilizer,air and temperature for tomato plants grown in non-arable greenhouses systematically,and provides a theoretic reference and support of technology popularizing of the water-fertilizer-air-temperature coupling irrigation for tomato plants in the greenhouses of Ningxia.The main results are as follows:1.Based on an orthogonal experiment of four factors and three levels,the article studies an optimal combination of irrigating water quota,fertilizer amount,dissolved oxygen concentration and water temperature in heat tubes in the 9 experimental treatments.Using range analysis and variance analysis,it is founded out that the heat pipe temperature,dissolved oxygen concentration,irrigating water quota and fertilizer amount in sequence have important influence on yield.Taking the yield as an index,single factor analysis showed that:yield with irrigation quota and fertilizer amount showed a convex parabola trend,but with dissolved oxygen content and the water temperature of the geothermal pipe showed basically increases linearly,The optimum parameter combination that affected the yield was A2B2C1D3,which means the irrigation quota,amount of fertilizer,dissolved oxygen,heat pipe temperature are 10 m3 per acre,12 kg per acre,6 mg/L and 35? respectively.Meanwhile,approximate analytic results about the order of primary and secondary factors,trends and the best combinations are obtained when tomato plant growth,photosynthesis and quality are considered as the primary index separately.2.An experimental study of water-fertilizer-air-temperature coupling model was conducted by adopting twice common rotation combined design and experiment scheme of four factors and five levels.A regression model for yields with irrigating water quota,fertilizer amount,oxygen concentration and heat pipe temperature is established,and passes the F test and t test which verify its significance and feasibility.Through analysis,the model showed that the yield is influenced largely by the irrigating water quota,fertilizer amount,heat pipe temperature and dissolved oxygen concentration in a sequence;the trends of yield with single factor show that the yield continuously increases with the four factors.And the optimum parameter combination is obtained when the yield is considered as an index.Meanwhile,regression models of indexes of plant growth,photosynthesis and quality are established;through analysis,optimal combination schemes of the four factors are obtained.