Research On The Effect Of Water-Fertilizer-Air-Heat Coupling On Growth,Photosynthetic,Yield And Quality Of Watermelon In Greenhouse

In this paper,the practical problems of severe sand leakage in the soil,high local groundwater salinity,the comprehensive control of no water,fertilizer,air and heat is not implemented in Ningxia helan county non-arable solar greenhouse.This experiment is based on drip irrigation under greenhouse,four-factor three-level orthogonal experimental design and four-factor five-level secondary general rotation combination design.Systematic study was conducted on the effects of water,fertilizer and gas heat coupling on the growth mechanism,photosynthesis,yield and quality of watermelon under drip irrigation in the greenhouse.It provides a theoretical basis and technical support for improving the quality,yield and efficiency of watermelon in the greenhouse.The main research results are as follows:(1)Using the four-factor and three-level orthogonal design method,the effects of different water,fertilizer,air and heat coupling treatment on the morphological,photosynthetic characteristics,fruit morphology,yield and quality of watermelon were studied.The experiment determined the primary and secondary factors affecting the growth index,photosynthetic index,yield and quality of watermelon,the law of single factor change,and the optimal combination of water,fertilizer,air and heat.Extremely poor analysis and analysis of variance of yields of various processed watermelons,The primary and secondary order of the four factors affecting watermelon yield were as follows:irrigation quota A>fertilizer amount B>dissolved oxygen C>geothermal heat pipe water temperature D.Among them,the irrigation quota and the fertilizing amount have a very significant effect on the yield,and the dissolved oxygen and geothermal heat pipe water temperature have no significant effect on the yield.Comprehensive analysis of various indicators to determine the optimal combination of factors for the A3B2C1D3,namely irrigation quota 6026 m3/hm2,fertilization amount of 75 kg/hm2,dissolved oxygen 6.5 mg/L,the water temperature of the geothermal pipe at 36 0C watermelon yield,The largest is 73842.42 kg/hm2.(2)Using four-factor five-level secondary general rotation combination design method,The effect of different coupling treatments of water,fertilizer,air and heat on the morphology,photosynthetic characteristics,fruit morphology,yield and quality of watermelon were studied.A regression mathematical model was established for the four parameters of watermelon morphology,photosynthetic characteristics,fruit morphology,yield,quality,and water,fertilizer,air and heat.Based on the analysis,the primary and secondary factors affecting the growth index,photosynthetic index,yield and quality of watermelon,the variation law of single factor,the interaction law,and the optimal combination of water,fertilizer,air and heat are discussed.The effect of each factor on watermelon yield was as follows:irrigation quota X1>fertilization amount X2>dissolved oxygen X3>water temperature of the geothermal pipe X4.Irrigation quota had a significant effect on watermelon yield,and other factors had no significant effect.Based on the analysis of water,fertilizer,air and heat coupled regression models established for the output indicators,It is concluded that the optimal combination of water,fertilizer,air and heat under the condition of yield greater than 60807.27 kg/hm2 is the irrigation quota 5352.02-5499.18 m3/hm2,fertilizer amount 61.84-66.49 m3/hm2,dissolved oxygen 7.42-7.58 mg/L and water temperature of the geothermal pipe 29.17-30.83℃.