The Research On The Water Physiological And Drought Tolerance Of A Few Hardwood Specific In Sunny Slope Mountain Of Daqing

The net photosynthetic rate,transpiration rate,water potential and saturation defic It and their correlation of branch of ten kinds trees such as Liaotungensis,tec werestuied in different dehydration by Plant photosynthesis meter and pressure chamber.physiological indicators of water such as at the initial loss point of the tugor .Physiological indicators of water such as at the initial loss point of the turgor(πp),etc were mensurated by PV technology to compare the drought tolerance of those being tested trees.The results showed as follow:(1)According toπp, the drought tolerance of being tested trees were evaluated. Those trees can be sorted four groups.The order was Tiliamongolica Maxim, Populus davidiana,Weigela Florida'Foliia purpureis', Acer negundo'Variegatum',Spiraea salicifolia,Acer negundo'Aureo-marginatum', Acer ginnala Maxim , Quercus liaotu ngensis Koidz,Acer negundo'Kellys Gold', Ostryopsis davidiana (from weak to strong ).(2)The result of correlation among photosynthetic rate, Transpiration rate, stomat al conductance and Saturation deficit showed that photosynthetic rate, Transpiration r ate and Stomatal conductance all declined with Saturation deficit increasing.the result can be showed by y=a+b(1-EXP(-kx)) and y=k/(1+aEXP(-bx)).The value of the flow of water that Net photosynthetic is 0 is called Potential compensation poin t of Net photosynthetic rate (ψnpc). The moreψnpc was large,the more adatability of t he plant to Drought stress was strong. The order of the adaptability of the being tested trees to Drought stress was T.mongolica Maxim.Populus davidiana, Weigela flrida'Foliia purpureis'.Acer negundo'Variegatum',Spiraea salicflia,Acer negundo'Aureo- marginatum',Acer ginnala Maxim, Quercus liaotungensis Koidz, Acer negundo'Ke llys Gold',Ostryopsis davidiana.(3)The parameters of tree species got from the PV curve, different water status of the relationship between photosynthetic rate and transpiration rate.indicators of charac teristics ofπp, ROWπp, Turgor and leaf water potential in the linear equation b value, the cell elastic modulus (εmax), absolute water potential that net photosynthetic is equ al to zero (water potential compensation pointψnpc) and relative maximum rate of c hange of transpiration rate (Xf) were selected as the main indexes to analysis of subor dinate function by analyzing characteristic of every parameters the stronger average d egree of membership subordinate function and the greater drought tolerance.the order of the adaptability of the being tested trees to drought stress was T.mongolica Maxim( 0.439),Populusdavi(0.4851),Weigela Florida'Foliia Purpureis'(0.5057) Acer regun do'Variegatum'(0.5080),SpiraeaSalicifolia(0.5655),Acernegundo'Aureo-marginatu m'(0.5186) Acer ginnala Maxim(0.5620),Quercus liaotungensis Koidz(0.5878),Ace rnegundo'KellysGold'(0.6310),Ostryopsisdavidiana(0.70567)from weak to strong.