小粒材小蠹伴生真菌的分离鉴定及其致病性研究

Isolation,Identification and Pathogenicity of Fungi Associated with Xyleborus saxeseni

为明确树状月季害虫小粒材小蠹伴生真菌的种类及其致病性,采用组织分离法分别对小粒材小蠹的成虫、幼虫、坑道、寄主变色边材和维管束进行真菌分离培养,结合形态学和分子生物学对所得菌株进行分类鉴定,通过柯赫氏法则进一步验证伴生菌的致病性。结果表明,5种分离材料共分离出伴生真菌10株,其中腐皮镰刀菌在不同分离材料中的分离率均为最高,是小粒材小蠹伴生菌的优势种群;腐皮镰刀菌、层出镰刀菌、藤仓镰刀菌对月季均有致病性,接种后的月季叶片和茎干出现病斑,叶片发病率分别为89.73%、34.15%、63.24%,发病面积分别为1.62、0.20、0.28 cm2;茎干发病率分别为55.56%、27.78%、30.00%,变色反应区长度分别为4.74、2.98、4.33 cm。该结果为进一步揭示伴生真菌与小粒材小蠹的相互作用关系提供了基础,为小粒材小蠹的综合防治提供科学的理论依据。

The aim of this study was to identify species and pathogenicity of fungi associated with Xyleborus saxeseni,a pest of tree rose.The fungi were isolated and cultured from adults,larvae,tunnels,discolored sapwood and vascular bundles.The obtained strains were classified and identified based on morphological and molecular biological features.The pathogenicity was tested by Koch's rule.Ten 10 fungi were isolated in total,and Fusarium solani had the highest incidence and was dominant among all the isolated materials.The inoculation to rose plants revealed that F.solani,F.proliferatum and F.fujikuroi were all pathogenic.Disease spots appeared in the leaves and stems of rose after inoculation,and leaf incidences were 89.73%,34.15%and 63.24%,respectively,and disease areas were 1.62,0.20,and 0.28 cm 2,respectively.Incidences of stem were 55.56%,27.78%and 30.0%,respectively,and lesion length of discoloration were 4.74,2.98,and 4.33 cm,respectively.The results further reveal the interaction between associated fungi and X.saxeseni,and provide a theoretical basis for integrated control of this beetle.In addition,it is also the first time to report X.saxeseni as a pest on rose.