P-V 曲線法에 의한 잣나무葉에 水分 特性에 關한 硏究

Characteristics of water relations paramenters obtained from pressure-volume curves in pinus koraiensis needles

This study is to investigate the change of the seasonal patterns of relative water relations parameters by the pressure-volume curves in pinus koraiensis needles. The osmotic potentials at full water saturated(Ψ0, sat) and at incipient plasmolysis(Ψ0, tlp) increased in growing season, while decreased in non-growing season. The maximum bulk modulus of elasticity(Emax), relative water content(RWCTLP), and relativefree water content(FWCtlp) at incipient plasmolysis in non-growing season were higher than these of growing season. The maximum pressure potential(Ψp, max) varied from 1.16 to 2.18MPa, torgor index(TI) varied from 3.1 to 4.7. The osmole number(Ns/dw) and symplastic water (Vo/DW) were variable seasonally. The maximum water content(Vt/DW) and apoplastic water(AW) were relatively high in early growing stage, and then decreased to needle aging. The pressure potential(Ψp) and water potential(Ψ) in winter needles were rapidly decreased with decreasing of relative water content. The matric potential occupied over 10 percent of water potential with less than-2.0 MPa.