昆蟲取食對楊樹富集Cd、Cu、Zn能力的影響1)

宋蕾　王月月　高璐璐　姜礅　侯超　嚴善春

(東北林業大學，哈爾濱，150040)

?

昆蟲取食對楊樹富集Cd、Cu、Zn能力的影響1)

宋蕾王月月高璐璐姜礅侯超嚴善春

(東北林業大學，哈爾濱，150040)

摘要為探討昆蟲取食對楊樹富集Cd、Cu、Zn能力的影響，對1年生小黑楊(Populus simonii×P. nigra)扦插盆栽苗，分別人工施加一定量的Cd、Cu、Zn，待苗木生長30 d后，接種舞毒蛾(Lymantria dispar)幼蟲，取食14 d取出，7 d后取樣，分析小黑楊根、莖、葉的干質量、重金屬質量分數、富集系數、轉運系數、貯存量。結果發現：各處理間根(8.0%～19.7%)、莖(61.0%～69.7%)、葉(17.3%～26.1%)干質量占植株的比例較為一致，不受重金屬脅迫或重金屬+昆蟲取食脅迫影響。在Cd脅迫或Cd+昆蟲取食脅迫下，小黑楊各部位對Cd的富集量及貯存量未產生顯著響應。在Cu、Zn脅迫下，小黑楊根莖葉對Cu、Zn的富集量極顯著增加(P<0.01)、貯存量顯著增加(P<0.05)；在Cu、Zn脅迫疊加昆蟲取食脅迫后，對Cu、Zn的富集量及貯存量顯著降低(P<0.05)，但其在小黑楊各部位的分布狀況不變。Cd在小黑楊各部位的富集量比較相近，Cu主要在莖部，Zn主要在葉部。Cd、Cu在莖部貯存量最高，達總貯存量的50%以上，而Zn量主要貯存在莖、葉部，達總貯存量的80%以上。各處理組的轉運系數(TF)由大到小為Zn、Cd、Cu，Zn脅迫降低了小黑楊的TF，Cd、Cu脅迫增加了小黑楊的TF；昆蟲脅迫增加了小黑楊對Cd和Zn的TF，降低了對Cu的TF。說明昆蟲取食能顯著影響楊樹對重金屬的富集能力。

關鍵詞小黑楊；重金屬脅迫；昆蟲取食

分類號X792.11；X503.235

Effects of Insect Herbivory on Cd,Cu and Zn Accumulation inPopulussimonii×P.nigra

Song Lei, Wang Yueyue, Gao Lulu, Jiang Dun, Hou Chao, Yan Shanchun

(Northeast Forestry University, Harbin 150040, P. R. China)//Journal of Northeast Forestry University，2016,44(3)：52-55.

For exploring the effects of insect herbivory on Cd, Cu and Zn accumulation in the poplar (Populussimonii×P.nigra) trees, we tested the one-year-old poplar potted cutting seedlings with various concentrations of heavy metal exposures. After 30-d heavy metal treatments, the gypsy moth (Lymantriadispa) larvae were added to the seedlings, and allowed to feed on the foliages for consecutive 14 d before removal from the tested seedlings. The dry weights, heavy metal concentraions, bio-concentration factors (BCF), translocation factors (TF) and storage capacities of the potted cutting seedlings were sampled and analyzed for 7 d after the larval removal. The dry weight percentages of roots (8%-19.7%)，stems (61.0%-69.6%) and leaves (17.3%-26.1%) were relatively consistent among the treatments, and they were not affected by heavy metal stress or by insect herbivory. Cd stress alone, or Cd plus insect herbivory did not show significant effects on the bio-concentration factors (BCF) and Cd storage capacities of the seedlings. Under the stress of Cu and Zn, accumulations of Cu and Zn in the seedling roots, stems and leaves were increased significantly (P<0.01), so did their storage capacities (P<0.05). However, insect herbivory by the gypsy moth larvae on the Cu or Zn stressed seedlings significantly decreased the accumulation and storage capacity of Cu and Zn (P<0.05) in all seedling parts. The amounts of Cd accumulation was similar among roots, stems and leaves of the popar seedlings. Cu was mainly concentrated in the stems, while Zn was mostly accumulated in the leaves. The storage capacities of Cu and Cd in the stems were the highest, exceeding 50% of the total storage capacity. The storage capacity of Zn was highest in the stems and leaves, accouting for above 80% of the total storage. The descending order of transfer factor (TF) in metal treatment groups was Zn, Cd and Cu. The Zn stress reduced the TF of the potted cutting seedlings, whereas, the stress of Cd or Cu increased the TF. Insect herbivory by the gypsy moth larvae increased the TF of Cd and Zn, but reduced the TF of Cu. Thus, the accumulation of heavy metal by the poplar seedlings was significantly affected by insect herbivory.

KeywordsPopulus simonii× P. nigra; Heavy metal stress; Insect herbivory

隨著經濟的飛速發展，人類活動引起的土壤金屬污染日益嚴重[1]，過量累積的重金屬降低了土壤質量，繼而影響作物產品的產量與質量，甚至通過植物的富集作用進入到食物鏈中，毒害動植物，危害人類健康[2-3]。相較于物理的、化學的重金屬污染治理方法，植物修復作為一種生物方法，更為經濟、環保、可持續[4]。Chaney et al.[5]提出利用超富集植物修復土壤重金屬污染，目前的研究已取得了一定成果，但大多數內容是針對草本植物的富集能力與修復能力的研究與探索[6-9]。一些木本植物由于生物量大、生長周期長、根系發達，可富集的重金屬量更大，并且不易造成二次污染，更適于作為修復植物改善土壤質量[10]?！?br>