Effects of Water and Fertilizers Supply on Soluble Sugar Content in Tomato Fruits

The effects of irrigation amount and fertilizer amount of nitrogen(N),phosphorus(P) and potassium(K) fertilizers on the soluble sugar content in tomato fruits are investigated in this paper.Through pot experiment,quadratic orthogonal regressive rotation design with four factors is used to establish a regression model for the relation between water and fertilizer amount and soluble sugar content in tomato.Meanwhile,single and coupling effects are analyzed too.The results show that if other factors are mean level,the soluble sugar content in tomato decreases firstly but then increases with the increase of the amount of irrigation,P fertilizer or K fertilizer.However,it is not affected by N fertilizer amount.The effects of P and K fertilizer amount on the soluble sugar content in tomato are larger than that of N fertilizer and irrigation amount.The interaction effects are displayed that the negative interaction effect between irrigation and N fertilizer amount and that between P and K fertilizer amount have significant influence on the soluble sugar content in tomato.