杉木对粗鞘双条杉天牛抗性的初步研究

A Preliminory Study of the Resistance of Cunninghamia lanceolata to Semanotus sinoauster

研究表明杉木韧皮具树脂道，被天牛蛀伤后泌出的树脂对天牛有杀伤作用，杀伤力的大小与天牛幼虫虫龄有关。初期幼虫最易被树脂胶死，胶死率达４３．５１％，中、后期幼虫的胶死率为４．９２％，初期幼虫的胶死率与泌脂量正相关（ｒ＝０．９６０２）。杉木受害后有较强的愈伤修复能力，能显著减轻天牛危害造成的损失。合理施肥能促进树脂分泌，提高对初期幼虫的胶死率，抚育间伐能显著提高杉木愈伤修复能力。

The research revealed that the basts of Cunninghamia lanceolata (Lamb.)Hook with resin flue could secrete resin which would destroy larvae of Semanotus sinoauster (Gressitt) after they were damaged by the beetles.The destructive capacity was related to larval stage.Immature larvae were easiest to be adhered to death by resin and the mortality amounted to 43.51%,but the mortality of mature larvae was only 4.92%.The rate of immature larvae adhered to death was positively related with the amount of resin(r=0.9602).The trees had strong recovery capacity and were able to decrease obviously the loss caused by the beetles.Reasonable fertilization could improve the secretion of resin so that more immature larvae were adhered to death,and intermidiation could increase greatly the recovery capacity of the trees.