Abstract:

Using water parameters which includes the osmotic potential while turgor was zero(φ_s^tlp)、the osmotic potential while turgor was maximum(φ_s ^sat)、the relative water content while turgor was zero(RWC^tlp)、relative osmotic water content while turgor was zero(ROWC^tlp)、the maximum cell flexibility module(ε^max) and the ratio of descendent of turgor with the leaf water potential(b),appraised the ability of maintaining turgor of Pinus massoniana seedlings from different families comprehensively.φ_s^tlp、φ_s ^sat、RWC^tlp、ROWC^tlp、ε^max and b of each family were relatively low,which showed the strong ability of maintaining turgor.Synthetically appraised,the ability of maintaining turgor of families No.456,83 and 20 and Taijiang provenance was strongest,then families No.75,38 and 127, and that of families No.23,464 and 186 was relatively weak.It meant the drought tolerance of P.massoniana seedlings had variation at intraspecies.With intensifying of drought stress,comparing family No.83 with 464,within certain water potential,b would be low,φ_s^tlpwould decrease while ε^maxwould increase.All these showed that osmoregulation of P. massoniana seedlings was enhanced within a limit drought stress.

Key words: Pinus massoniana, Family, Seedling, Drought stress, Water parameter