Modeling and Prediction of Dry Matter Production by Tomato Plants in Year-round Production Based on Short-term, Low-truss Crop Management

Abstract

We investigated dry matter (DM) and fruit production of tomato plants, the effects of CO₂ levels on DM production, and light-use efficiency (LUE) in a tomato production system based on short-term, low-truss crop management during six consecutive periods over one year in a commercial greenhouse. The CO₂ concentration, total dry matter production (TDM), and LUE differed significantly among the periods. Since LUE was significantly correlated with the mean daytime CO₂ concentration, we modeled LUE empirically from that. We developed a model to predict LUE and DM production of tomato plants and validated the model using data from the six periods. We accurately predicted LUE and TDM within a range of ca. 400 to 650 µmol·mol⁻¹ daytime CO₂ concentration. However, when daytime CO₂ concentration was beyond this range, or when a management failure such as inadequate irrigation occurred, predicted values differed significantly from observed values.