Abstract
The light-use and water-use efficiencies of tomato plug sheets in the greenhouse were estimated continuously for 15d based on micrometeorological and weighing methods. The light-use efficiency, defined as chemical-energy transformation rate by photosynthesis per unit shortwave radiation flux density, increased with increases in leaf area index and then remained stable at about 2×10-2 - 4×10-2 J J-1 when leaf area index was higher than about 1.0. The light-use efficiency decreased with increases in shortwave radiation flux density. The water-use efficiency, defined as dry matter production rate per unit evapotranspiration rate, also increased with increases in leaf area index and then remained stable at about 3×10-3 - 4×10-3 g dry matter g-1 H2O when leaf area index was higher than about 0.5. The accumulated light-use and water-use efficiencies for 15d were 1.8×10-2 J J-1 and 2.7×10-3 g dry matter g-1 H2O, respectively.
