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Growth of tomato seedlings: an approach with the logistic model as a function of the product of thermal efficiency and photosynthetically active radiation

ABSTRACT

This study aimed to evaluate the use of the product of thermal efficiency and photosynthetically active radiation (TEP) to model the growth of tomato seedlings across different growing seasons. The work was conducted in a completely randomized design with four replicates in two seasons (summer/autumn and winter/spring). Height, diameter, the Dickson’s Quality Index (DQI), and total plant mass (TPM) were measured at 15, 20, 25, 30, 35 and 40 days after sowing (DAS). The logistic model was fitted for each measured variable as a function of TEP, and the partial derivatives of the fitted function estimated the critical points. The results demonstrated that the logistic function effectively explained the nonlinear relationships of seedling growth. The fit quality parameters showed high fitted coefficients of determination and low values for the standard error of fit, residual standard deviation, and intrinsic and parametric nonlinearity. It was possible to characterize the growth process of tomato seedlings in both growth periods investigated. The logistic model fitted for the studied variables as a function of TEP becomes an accurate model capable of describing growth aspects of tomato seedlings, such as growth estimation, growth speed, and growth rate, essential parameters for decision-making in tomato cultivation.

nonlinear; precocity; production; solar radiation; temperature

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