Variations of Light Interception and Biomass Prediction Model of Red Spinach (Amaranthus gangeticus) in Plant-Factory System

摘要

Artificial lighting given in plant-factory planting system is inseparable from uniformity problem. Spatial variation in the catch of light (radiation) will occur due to the position of the plant against the lamp. The purpose of this research was; a) to determine the relationship between biomass growth and the intensity of artificial irradiation in plant-factory systems, and b) to apply the mechanical model of plant growth basedon radiation interception and temperature. Six boxes containing red spinach plants were placed on plant factory system in the form of two racks (each rack is placed 3 boxes). In each box, intercepted light was measured and then converted to radiation value. The air temperature in plant-factory space was measured during growth to harvest. Observations showed that there was a difference in light interception in plantfactory growing spaces that caused variations in plant biomass growth. Mathematical models were used to predict the relationship between light interception and biomass growth. This research concludes that the variation of light occurring in plant-factory planting cannot be ignored, as this leads to markedly differentplant-end biomass differences. Modeling can be applied to design optimal lighting to improve plant biomass.