Effect Of The Ratio Of Nutrient Liquid Nitrogen,Phosphorus And Potassium On The Yield And Quality Of Tomato Cultivated In Protected Substrate

In this experiment,spring and autumn crops were cultivated in solar greenhouse,and "Jingcai No.8" was used as the test material.The orthogonal experimental design was adopted,and three levels of factors of N,P and K were set,which were N:2,4 and 8 respectively.P:0.67、1.33、2;K:8,12 and 16.By studying the ratio of nutrient liquid nitrogen,phosphorus and potassium in substrate culture,the changes of growth,photosynthesis,yield and quality of tomato in substrate culture under different nitrogen,phosphorus and potassium treatments were compared and analyzed,so as to clarify the reasonable ratio of nutrient liquid nitrogen,phosphorus and potassium in substrate culture and provide technical support for the production of high-quality taste fresh tomato products.The main results are as follows:1.The experiment of different ratios of N,P and K in nutrient solution facility substrate culture in spring showed that when N=4 mmol/L and P=0.67 mmol/L,the RubisCO activating enzyme RCA,fructose 1,6-diphosphatase FBPase,ribulose-1,5-diphosphate carboxylase Rubisco,fruit shape index,soluble solids and Vc of tomato all reached the maximum,while organic acids.When K=12 mmol/L,transpiration rate,stomatal conductance,Sedum-1,7-diphosphatase SBPase,ribulose-1,5-diphosphate carboxylase RubisCO,relative grwth rate of stem diameter,single fruit weight,yield per plant,soluble sugar,Vc and sugar-acid ratio all reached the maximum.The fruit with N:P:K=4:0.67:12(T4)contains 52 kinds of volatile aromatic substances,including 4 kinds of alkanes,12 kinds of alcohols,4 kinds of ketones,16 kinds of aldehydes,3 kinds of esters and 13 others,accounting for 83.41%of the total content of chromatographic components.The nutrient solution supply is N:P:K=4:0.67.2.The experiment of different ratios of N,P and K in nutrient solution facility substrate culture in autumn showed that when N=4 mmol/L,the soluble solids,organic acids,Vc and soluble sugar of tomato fruit reached the maximum value,while the relative growth rate of plant height,net photosynthetic rate,transpiration rate,single fruit weight,single plant yield and fruit shape index remained high and had no significant difference from the highest level.When P=1.33 mmol/L,the relative growth rate of stem diameter,transpiration rate,stomatal conductance,intercellular CO2,soluble solids,Vc and organic acids all reached the maximum,while the relative growth rate of plant height,net photosynthetic rate,single fruit weight,single plant yield and fruit shape index all remained at the maximum,and there was no significant difference between them.When K=16 mmol/L,transpiration rate,Vc,soluble solids and fruit shape index all reached the maximum value,while the relative growth rate of stem diameter,relative growth rate of plant height,net photosynthetic rate,stomatal conductance,single fruit weight,single plant yield and organic acid all remained at the maximum value without significant difference from the highest level.Combined with the actual production in terms of comprehensive yield and quality,it is considered that the nutrient solution formula of N:P:K=4:1.33:16 in autumn stubble substrate culture is the best scheme,which can produce fresh tomatoes with higher quality and better taste,and ensure a certain yield.