EFFECT OF DAY/NIGHT TEMPERATURE CONDITIONS ON CO2 EXCHANGE RATE AND CO2 BALANCE OF DENDROBIUM EKAPOL PANDA NO.1.
Effects of the combinations of day/night temperature on CO2 exchange of Dendrobium ekapol Panda No. 1 were investigated under day leaf temperature (DLT) from 20 to 30°C, night leaf temperature (NLT) from 15 to 35°C, photosynthetic active radiation of 420 μ mol/m2/s, and day length of 10 hours. CO2 exchange of D. ekapol leaf showed the typical diurnal patterns of CAM type photosynthesis. The diurnal CO2 exchange rates and CO2 balances were affected by the combinations of DLT and NLT. Maximum CO2 balance of a whole day was observed in the following conditions: 25 and 30°C DLT and 25°C NLT. Under low NLT and DLT conditions the amount of nocturnal CO2 influx was remarkably decreased. When NLT was higher than DLT, the CO2 efflux was observed at the beginning of the dark period, and the CO2 balance of the dark period decreased drastically. The results indicate that the combinations of day and night temperature played important roles in the growth of D. ekapol.
Sekizuka, F., Nose, A., Kawamitu, Y., Akinaga, T., Taira, C. and Onaha, A. (1992). EFFECT OF DAY/NIGHT TEMPERATURE CONDITIONS ON CO2 EXCHANGE RATE AND CO2 BALANCE OF DENDROBIUM EKAPOL PANDA NO.1.. Acta Hortic. 292, 187-194