Growth Model of Common Ice Plant (Mesembryanthemum crystallinum L.) Using Expolinear Functions in a Closed-type Plant Production System

The objective of this study was to make growth and yield models for common ice plant (Mesembryanthemum crystallinum L.) using expolinear functional equations in a closed-type plant production system. Three-band radiation type fluorescent lamps with a 12-hours photoperiod were used, and the light intensity was 200 mu mol.m(-2).s(-1). Nutrient film systems with three layers were used for plant growth. Environmental conditions, such as air temperature, relative humidity and CO2 concentration were controlled by an ON/OFF operation. Leaf area, shoot fresh and dry weights, light use efficiency of common ice plant as function of days after transplanting, accumulative temperature and accumulative radiation were analyzed. Leaf area, shoot fresh and thy weights per area were described using an expolinear equation. A linear relationship between shoot dry and fresh weights was observed. Light use efficiency of common ice plant was 3.3 g.MJ(-1) at 30 days after transplanting. It is concluded that the expolinear growth model can be a useful tool for quantifying the growth and yield of common ice plant in a closed plant production system.