落叶松八齿小蠹伴生真菌富士长喙壳的致病性研究

Pathogenicity of Ceratocystis fujiensis Strains Associated with Ips subelongatus

研究人工接种条件下落叶松八齿小蠹伴生真菌富士长喙壳(Ceratocystis fujiensis)的3个菌株对长白落叶松样树和木段的致病性,结果表明,致病力最强的菌株为CF3,CF1、CF2致病力差异不大。固体接种韧皮部坏死反应区域稍大于液体接种,说明菌丝体容易在木质部与韧皮部间定殖,树体内营养条件适合伴生真菌生长。3个菌株对木段造成的伤害显著高于对样树造成的伤害,说明在伴生真菌入侵的同时样树产生了积极的防御反应。在接种样树和木段产生的坏死反应及蓝变区域内均可以分离到接种真菌。

This research investigated the pathogenicity of 3 associated fungal strains of Ceratocystis fujiensis which were isolated from Ips subelongatus on Larix olgensis.The results showed that CF3 strain had the strongest virulence,and CF1 and CF2 had moderate.The phloem necrotic reaction zone by solid inoculums was larger than that by liquid inoculums,which showed that the mycelium of C.fujiensis could colonize easily between the xylem and phloem.The nutrition condition in the wood fitted the growth need of associated fungi.The three strains did more damage to logs than to living sample trees.The invasion of associated fungus could induce positive defense response of living sample trees.The associated fungi could be isolated from the phloem necrotic reaction zones and the blue stain sections.