Modelling Dry Matter Production and Partitioning in Sweet Pepper

摘要

Models predicting growth and yield have been developed for a large number of crops. This paper describes a dynamic, mechanistic model for sweet pepper, addressing issues such as leaf area expansion, dry matter partitioning and validation. Leaf area formation and organ initiation are simulated as a function of temperature sum. Light absorption and photosynthesis are calculated for a multi-layered uniform canopy. Leaf photosynthesis is calculated for the various leaf layers according to the biochemicalmodel of Farquhar, and integrated to canopy photosynthesis. Net assimilate production is calculated as the difference between canopy gross photosynthesis and maintenance respiration. The net assimilate production is used for growth of the different plant organs and for growth respiration. Fruit set is simulated as a function of source and sink strength and temperature. Assimilate partitioning between vegetative parts and individual fruits is simulated on the basis of the concept of sink strengths. Thesink strength of each individual fruit is calculated as a function of its temperature sum from anthesis. The sink strength of the vegetative parts is calculated as a function of temperature only. A wide range of experimental data show that leaf area is linearly related to the temperature sum from planting. The model was validated on the basis of six experiments in The Netherlands and France. Simulation of dry matter production and partitioning under a wide range of conditions showed that model results agreed well with measurements. Some directions for further improvements are discussed.