A Study On Leaf Water Potential And Drought Resistance Of Dominant Shrubs In The Arid Valley Of The Upper Minjiang River

Leaf water potential is a very important physiological index reflecting the water condition of plants,and it is also an im portant index to determ ine the drought resistance ability of plants.This research used PSY PRO dewpoint water potential m eter to m easure the leaf water potential of several dom inant shrubs in the arid valley of the upper M injiang river in different tim e and slope direction.Through the analysis of these indicators: leaf water potential value of different plant,seasonal change of leaf water potential,the influence of slope direction to leaf water potential,the relationship between soil water potential and leaf water potential and chlorophyll,we can finally insure the drought resistance of each plant.This study selected 6 kinds of widespread shrubs,they are Cam pylotropis wilsonii Schindl,A jania achilloides,Rabdosia,Caryopteris glutinosa Rehd,A rtem isia gm elinii and Sophora davidii(Franch.).The com m on plants of Y in and Y ang slopes are Cam pylotropis wilsonii Schindl,A jania achilloides and Rabdosia am ong them.Caryopteris glutinosa Rehd only exist in sunny slope.Sophora davidii(Franch.)and A rtem isia gm elinii only exist in shady slope.The results are as follows:(1)The seasonal variation of leaf water potential of each plant is very obvious,which is the lowest in late A pril,the highest in late July and slightly lower in late O ctober than in late July.The ranks of seasonal variation significance level of each plants are those,shady slope: A jania achilloides> Sophora davidii(Franch.)> Rabdosia> A rtem isia gm elinii > Cam pylotropis wilsonii Schindl,sunny slope: Cam pylotropis wilsonii Schindl> Rabdosia> Caryopteris glutinosa Rehd> A jania achilloides.(2)The influence of slope direction to leaf water potential is significant.Leaf water potential in shady slope is obviously higher than that in sunny slope.The rank of slope direction influence to leaf water potential is that: A jania achilloides> Rabdosia> Cam pylotropis wilsonii Schindl.(3)The effects of slope direction and season are obvious to leaf water potential and soil water potential.In addition,there was a consistent pattern of change,and the leaf water potential of the six plants of yinyang slope was highly correlated with the soil water potential,The correlation between leaf water potential and soil water potential of shady slope plants is stronger than that of suuny slope plants.(4)There was a negative correlation between leaf water potential and chlorophyll in each plant,but it was not obvious.Leaf water potential is not related to chlorophyll a/b.(5)A fter synthesizing the results of leaf water potential and chlorophyll,the drought resistance ranks of each plant are those,Shady slope plants:Cam pylotropis wilsonii Schindl> A rtem isia gm elinii> Rabdosia> Sophora davidii(Franch.)> A jania achilloides,sunny slope plants: Rabdosia> Caryopteris glutinosa Rehd> Cam pylotropis wilsonii Schindl> A jania achilloides.