Comparison of Vegsyst and Hortsyt models: Two models of growth of greenhouse crops

Abstract

The HortSyst model is a new discrete-time model to describe the dynamics of photothermal time (PTT), dry matter production (DMP), N uptake (Nup), leaf area index (LAI) and rate of transpiration (ETc) of greenhouse crops, it has 13 parameters. The model assumes that crops do not have water and nutrient limitations. The input variables of the model are hourly measurements of air temperature, relative humidity, and the integral of solar radiation. Two experiments were carried out in a greenhouse, with hydroponic tomato cv. "CID F1" at a density of 3.5 plants m-2, autumn-winter and spring-summer cycle, in Chapingo, Mexico. The first experiment was transplanted on August 21, 2015 and the second experiment on April 24, 2016. A weather station was installed inside the greenhouses, temperature and relative humidity were measured with a model S-TMB-M006 sensor and radiation global sensor S-LIB-M003. The objective of this research is to compare two growth models for tomato in greenhouses. According to the adjustment of its predictions against the measurements it can be of help in the supply water and nitrogen.