The effects of La3 + on the growth and the ATPases activities of plasma membrane (PM) vesicles isolated from
Casuarina equisetifolia seedlings under artificial acid rain (pH 4. 5) stress were studied. The results show that the height ,
length of roots , fresh weight and PM H+2ATPase activites of Casuarina equisetifolia seedlings increase by the treatments of
soaking seeds in LaCl3 solutions with lower concentrations , and those can reach their peak values by treating with 200 mg
·L - 1 La3 + . However , in comparison with the CK, those are inhibited by the higher La3 + concentrations ; PM Ca2 +2AT2
Pase activity is inhibited with the treatments of La3 + . The results also reveal that the H+2ATPase activity and the growth
of cell enlarge have a remarkable positive correlation , and La3 + activating H+2ATPase can facilitate plant growth. La3 + al2
so can alleviate cytosolic acidification of plant under acid rain stress and indirectly maintain the stability of intracellular
environment . In order to resistant to acid rain and accelerate the growth of Casuarina equisetifolia , the suitable range of
La3 + concentrations to soak seeds for 8 h is 50～200 mg·L - 1
