Study on the kinetics of tomato storage quality under water and fertilizer coupling

In order to make full use of the yellow sand resources in Xinjiang, China, under the mixed substrate cultivation mode with the volume ratio of yellow sand to slag of 5:3, in order to improve the yield and storage quality of tomato, provide optimized water and fertilizer management scheme, and explore the dynamic changes of water and fertilizer coupling on the quality of Tomato during storage, a dynamic model of tomato fruit quality under 4 ℃ storage was established.The tomato variety 'Qinshulingyue' was used as the experimental material. Irrigation amount, nitrogen application amount, phosphorus application amount, and potassium application amount were considered as factors, and a half of the four-element quadratic general rotary combination design (20 treatments) was employed. The tomato fruits were stored at 4°C for 28 days, with samples collected every 7 days to assess the quality of the fruits and analyze the effect of water and fertilizer coupling on tomato storage quality. Pearson correlation analysis and a combined evaluation method were used to comprehensively evaluate the indicators, and a response model was constructed to establish the relationship between the comprehensive score of tomatoes and the four factor levels.The results indicated that the reasonable ratio of water and fertilizer could enhance the quality of tomatoes, while excessive or inadequate water and fertilizer parameters could reduce the fruit quality. The changes in tomato hardness, soluble sugar, lycopene, and vitamin C content during storage were consistent with the first-order kinetic equation. Through a comprehensive analysis of tomato quality index (TQI), an irrigation amount of 602 mm/hm ² , nitrogen application rate of 570 kg/hm ² , phosphorus application rate of 70 kg/hm ² , and potassium application rate of 738 kg/hm ² under water and fertilizer coupling could effectively improve the fruit quality of stored tomatoes, and the equation fitting degree and storage resistance were also satisfactory.