树木气孔浸润级与SO2伤害及ABA的防护作用

以常见绿化树种为材料,通过实地测定和熏烟实验,探讨了气孔浸润级与树木SO₂伤害的关系及ABA的防护效应.结果表明,在特定环境下,相同树种的气孔浸润级较为稳定,不同树种的气孔浸润级差异较大;浸润级与叶绿素结合度呈负相关变化,但不明显;与K⁺渗出量呈正相关(r=0.92,α＜0.01),并按95%的置信度绘制了伤害预测图.不同SO₂浓度条件下,对同一树种的气孔浸润级的影响甚小,不超过一个等级,K⁺渗出量则依大气SO₂浓度和树木吸S量的增加而增多.气孔浸润级依ABA溶液处理浓度增大而降低,K⁺渗出量也相应减少,经2.5mol·L^-1×4h剂量的SO₂熏烟,预涂30mol·L^-1ABA者,降低了1.5～3个浸润级,K⁺渗出量减少36.5%～54.8%,其测定值与自然对照值相近,防护作用显著.

Tree stomatal infiltration and SO2 injury and protection effect of ABA

This paper deals with relation between tree stomatal infiltration and SO₂ injury and the protection effect of ABA. Experiments of SO₂ smoking to the selected trees were carried out and the data were collected in the field. The results show that stomatal infiltration was a comparably constant index for certain tree species. The infiltration of trees is negatively correlated with the combine extent of chlorophy, but not obviously. The index is also positively correlated with K⁺ efflux in leaf(r=0.92, α<0.01). In the experiment of SO₂ smoking, the effect on infiltration of same species under different SO₂ concentration was little, less than one grade, while K⁺ efflux increased with the increment of SO₂ amount absorbed by the leaves. When the leaves were sprayed with ABA solution, the higher the ABA solution concentration was, the lower the K⁺ efflux was. When leaves sprayed with ABA solution were smoked with 2.5 mol·L^-1 for four hours, the infiltration of leaves with 30 mol·L^-1 ABA solution dropped 1.5～3 and K⁺ concentration decreased 36.5%～54.8% on leaves. It indicates that the ABA solution on leaves has remarkable effect of protection of SO₂ injury.