铜对凤丹生长、生理及体内矿质元素吸收分配的影响

Effects of Cu on Paeonia ostii growth,physiology,and element absorption and allocation

通过盆栽试验,研究了凤丹(Paeonia ostii)在添加低(300mg.kg-1)、中(600mg.kg-1)、高(900mg.kg-1)铜浓度处理下的耐性。结果表明:凤丹的株高增长、地茎加粗、主根增粗及伸长、根系及地上部干重的积累等对铜具有较强的耐性。各添加铜处理下,地上及地下耐性指数均>0.5。各铜处理下根部SOD活性显著下降,但低铜浓度下叶片SOD活性升高;各铜处理下根部及叶部POD活性先升后降;低、中铜浓度下根部及叶部MDA含量均未有显著增加;根、叶内可溶性糖及可溶性蛋白含量均随铜浓度升高而逐渐上升;叶绿素a、叶绿素b、叶绿素总量及叶绿素a/b均在中浓度铜处理下上升至最高。根、茎部铜含量均随铜浓度增加而上升,叶部铜含量则先升后降。铜处理下根、茎、叶对铜的富集系数均<1。铜处理抑制凤丹根部对P、Ca的吸收,但促进P、K向上运输;低、中铜浓度下叶对Mg积累增加,高浓度降低。铜处理抑制根对Fe、Mn的吸收,低、中铜浓度促进叶对Fe、B的积累及Fe、Mn、Zn、B的向上运输,凤丹各部位对Zn的积累不受铜处理影响。

A pot experiment was conducted to study the tolerance of Paeonia ostii to different levels（low,300 mg·kg-1;medium,600 mg·kg-1;and high,900 mg·kg-1）of added Cu.P.ostii had strong tolerance to Cu.The plant height and root collar growth,taproot thickening and elongation,and biomass of roots and shoots were less affected.Under the Cu treatments,the tolerance index of roots and shoots was higher than 0.5.The superoxide dismutase（SOD）activity in roots decreased significantly under the Cu treatments,but that in leaves increased significantly under low Cu treatment.With increasing concentration of added Cu,the peroxidase（POD）activity in roots and leaves decreased after an initial increase.The MDA both in roots and in leaves did not have a significant increase under low and medium Cu treatments.The soluble sugar and soluble protein contents in roots and leaves increased with increasing concentration of added Cu,while the contents of chlorophyll a,b,and a＋b and the chlorophyll a/b ratio were peaked at medium Cu treatment.With increasing concentration of added Cu,the Cu content in roots and stems increased,while that in leaves decreased after an initial increase.The Cu enrichment coefficient in each part of the plant under the Cu treatments was less than 1.The Cu treatments led to a significant reduction in the P and Ca absorption,but promoted the upward translocation of absorbed P and K.Low and medium Cu treatments promoted the Mg accumulation in leaves,but high Cu treatment inhibited it.The Fe and Mn accumulation in roots was inhibited under the Cu treatments,while the Fe and B accumulation in leaves and the upward translocation of absorbed Fe,Mn,Zn,and B were promoted under low and medium Cu treatments.The accumulation of Zn in each part of P.ostii was less affected by the Cu treatments.