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

This dissertation is based on the solar greenhouse of non-cultivated land in Helan County of Ningxia,in view of the serious leakage of water and fertilizer in sandy soil in this area,the water and fertilizer have not been regulated reasonably,and long-term drip irrigation under mulch leads to lower oxygen content in the soil of crop root zone,lower soil temperature in winter and spring nights inhibits crop growth and other practical problems.Four factors,three levels orthogonal design and four factors,five levels quadratic general rotary combination design method are adopted in this experiment.The effects of water,fertilizer,gas and heat coupling on the growth,photosynthesis,quality and yield of pepper were systematically studied,and the influencing regularity and mechanism were revealed,and the optimal combination scheme was determined,provide theoretical basis and technical support for high quality,high yield and precise water-saving irrigation of greenhouse fruits and vegetables.The main conclusions are as follows:(1)The effects of different treatment with water,fertilizer,gas and heat on growth,photosynthesis,quality and yield of pepper were studied by four-factor and three-level orthogonal design method.Through range analysis and variance analysis,the order of primary and secondary effects of water,fertilizer,gas and heat on growth index,photosynthetic index,quality and yield of pepper was obtained,and the optimal combination formula was determined,Determine the optimal combination scheme.According to the analysis of pepper yield under different treatments,the order of four factors affecting pepper yield is irrigation quota A>fertilier quota B>dissolved oxygen C>geothermal pipe water temperature D.Irrigation quota has a very significant impact on yield,fertilization quota has a significant impact on yield,but dissolved oxygen and water temperature of geothermal pipe have no significant impact on it.Reference combination A3B2C1D3,considering cost and other factors,and dissolved oxygen C is the secondary factor,the optimal combination is A3B2C1D3:irrigation quota is 14 m3/667 m2,fertilizer quotat is 5 kg/667 m2,dissolved oxygen content is 7.5 mg/L,water temperature of geothermal pipe is 37 C,the highest yield of pepper is 58597.40 kg/hm2.(2)The effects of different irrigation quota,fertilizer quota,dissolved oxygen and water temperature of geothermal pipe coupling treatments on growth index,photosynthesis,quality and yield of pepper were studied by using four-factor,five-level,quadratic general rotary combination design method.By establishing the regression model of each index and four factors of pepper,the main and secondary factors affecting the various indicators of pepper,the law of single factor change,the law of interaction of four factors and the optimal combination were obtained.The effect of irrigation quota X1>fertilization amount X2>dissolved oxygen X3>geothermal pipe water temperature X4 on pepper yield index was in turn large and small.Among them,only irrigation quota and fertilization amount had a significant effect on pepper yield.The established water-fertilizer-air-thermal coupling regression model was analyzed.When the yield of pepper was more than 40029.22 kg/hm2,325 combination schemes were put forward.The water-fertilizer-air-thermal coupling schemes under the experimental conditions were irrigation quota 12.29-12.62 m3/667 m2,fertilization rate 5.09-5.40 kg/667 m2,dissolved oxygen 8.42-8.58 mg/L and water temperature of geothermal pipe 32.44-33.56 C.