Design and Test of a Simulation Model of Tomato Growth and Yield in a Greenhouse

Abstract

A deterministic model of the growth of greenhouse tomatoes (Lycopersicon escu-lentum Mill), written in Pascal computer language, was developed based on a leaf assimilation model, a respiration theory, and a theory that the photosynthesis rate is controlled by both environmental conditions and leaf carbohydrate level. The model was applied to estimate the effect of carbon dioxide enrichment on tomato fruit yield, and tested with data obtained from two experiments conducted in Col-lege Station, Texas, U. S. A. in 1983 through 1984. Tomatoes were grown at 340, 700, and 1000 ppm (on a volume basis) of carbon dioxide (C02) in three 2 x 2 x 10 m translucent chambers inside a double-layered, polyethylene greenhouse. The measured values of the C02 assimilation rate and the dry mass accumulation rate of tomatoes were consistently higher than the calculated ones, but the predic-tion of the fruit growth and yield were rather accurate.