水分胁迫对冷蒿和差不嘎蒿体内水分状况的影响

Water State of Artemisia Frigida and Artemisia Halodendron under Different Water Stress Conditions

在土壤正常水分条件下，冷蒿的ψｗ，ψπ和ψπ１００远远低于差不嘎蒿，ＲＷＤ、Ｖａ及Ｖａ·Ｖｓ－１远远大于差不嘎蒿，维系其生命活动的膨压只占差不嘎蒿的３０％。土壤极端干旱时，差不嘎蒿的上述参数发生大幅度变化，抗旱能力随之提高。极旱的午后，二种灌木均遭旱害威胁，其水分状况参数值（ψｗ，ψＯ、Ｖａ和ＲＷＤ）相差很小。旱后复灌的情况下，差不嘎蒿上述参数同样发生大幅度变化，各参数值可恢复到对照水平；冷蒿在干旱和复灌期间参数相对变化较小。多水环境使二种灌木束缚水含量明显提高，从外观生长状况看差不嘎蒿优于冷蒿。

The parameters of ψ w,ψ π,ψ π 100 are far lower and the RWD, Va ,Va/Vs are much higher of Artemisia frigida than that of Artemisia halodendron in the soil moisture 23%(soil volumn) condition. The cell pressure potential of A.frigida is only 30% of A. halodendron . In the morning, the above parameters of A. halodendron in extremly drough soil changed more than that of A.frigida, the drought resistance ability increased; in afternoon, the parameters ( ψ w, ψ o, Va and RWD )of both plants were almost the same. After re irrigation, the above parameters of both A.halodendron and A. frigida recovered to be the contrast level. Under the condition of soil water was 33%, the bound water percent of the both plants increased.