华山松大小蠹对华山松韧皮部营养和矿物元素的利用

Utilization of Nutritients and Mineral Elements in Pinus armandii by Chinese White Pine Beetle (Dendroctonus armandi)

对健康和蓝变真菌侵染的华山松韧皮部以及华山松大小蠹排泄物中粗蛋白、粗脂肪、粗纤维、淀粉、还原性糖、可溶性总糖、游离态氨基酸和Na,K,Ca,Mg,Fe,Cu,Mn,Zn等8种元素进行分析,结果表明:华山松大小蠹对寄主华山松营养物质的利用率依次为:还原性糖>粗脂肪>可溶性总糖>粗纤维>淀粉>粗蛋白。华山松韧皮部的17种游离态氨基酸中含有华山松大小蠹必需的9种氨基酸;华山松大小蠹对寄主华山松韧皮部组织内的Na,K,Ca,Mg,Fe,Cu,Mn,Zn等8种矿物元素需求量存在明显差异,其中对K元素的需求量最大,而对Cu,Mn,Zn3种元素的需求量较小。同时,华山松大小蠹共生真菌能够加速华山松木质部和韧皮部中营养的分解转化,为华山松大小蠹在被害华山松韧皮部和木质部间的生存和发育创造条件,并加速被害华山松树势的衰弱和死亡。

Crude protein,crude fat,crude fiber,starch,reducing sugar,total soluble sugar,free amino acids,four major inorganic elements（Na,K,Ca,Mg）and four trace elements（Fe,Cu,Mn,Zn）in the phloem of healthy and a blue stain fugus-infected Pinus armandii,and in the excrement of Chinese white pine beetle（Dendroctonus armandi）were measured.The results showed that the utilization efficency of nutrition by D.armandi was：reducing sugarcrude fat total soluble sugar crude fiber starch crude protein.There were 17 free amino acids in the phloem of P.armandii,among which nine are requaired by D.armandi.In D.armandi＇s excrement,K content was the highest among the major elements of Na,K,Ca,Mg,and Fe content was higher that of the other trace elements probably because it has great influence on the growth of blue stain fungus.Meanwhile,the blue stain fungus was able to decompose the nutrients from the phloem to the xylem,which provided more nutrients for the bark beetle,thus accelerating the weakness and death of the attacked host tree.