Diurnal changes of stomatal conductance, transpiration rate, and photosynthetic rate in Pinus densiflora Sieb. et Zucc. saplings on different soil water conditions

Abstract

To elucidate differences of physiological characteristics in Pinus densiflora Sieb. et Zucc. saplings under different soil water conditions, diurnal changes of the stomatal conductance, the transpiration rate, and the net photosynthetic rate for saplings under pF 1.8- and pF 4.2-soil water condition were measured. pF 4.2-treatment saplings tended to close the stomata and reduce the water loss constantly. However, no distinct differences in the net photosynthetic rates were observed between soil water conditions. These results suggested that pF 4.2-treatment saplings under long-term water stress maintained the high net photosynthetic rates with reducing water loss.