取食洋白蜡和旱柳光肩星天牛幼虫肠道中的细菌多样性差异及关键纤维素降解细菌筛选  

Differences in Bacterial Diversity and Key Cellulose-Degrading Bacteria in the Intestinal Tract of Anoplophora glabripennis(Coleoptera:Cerambycidae)Larvae Feeding on Fraxinus pennsylvanica and Salix matsudana

作　　者：贾若峰 谷奇 孙一鸣 陆鹏飞[1] 俱世博 乔海莉[2] Jia Ruofeng;Gu Qi;Sun Yiming;Lu Pengfei;Ju Shibo;Qiao Haili(Key Laboratory for Silviculture and Conservation of Ministry of Education,Beijing Forestry University,Beijing 100083;Institute of Medicinal Plant Development,Chinese Academy of Medical Sciences and Peking Union Medical College,Beijing 100193)

机构地区：[1]北京林业大学省部共建森林培育与保护教育部重点实验室,北京100083 [2]中国医学科学院、北京协和医学院药用植物研究所,北京100193

出　　处：《林业科学》2023年第4期117-131,共15页Scientia Silvae Sinicae

基　　金：国家重点研发计划课题(2017YFD0600103);国家自然科学基金面上项目(31570643);国家级大学生创新创业训练项目(G201910022008)。

摘　　要：【目的】从肠道细菌多样性角度探究光肩星天牛幼虫对传统抗性树种洋白蜡的适应性原因。【方法】基于16S rDNA高通量测序技术,分别对用洋白蜡、旱柳饲喂的光肩星天牛幼虫肠道细菌进行了分子鉴定及多样性分析;然后通过富集培养,从未经饲喂的幼虫中筛选出了31株纤维素降解细菌,以透明水解圈直径(D)/菌落直径(d)为标准初步测定了各菌株纤维素降解能力;对降解能力最强的4个菌株进行了滤纸复筛试验。【结果】使用洋白蜡饲喂后,厚壁菌门、芽孢杆菌纲、乳杆菌目、链球菌科、乳球菌属为优势类群;使用旱柳饲喂后,厚壁菌门、芽孢杆菌纲、乳杆菌目、肠球菌科、肠球菌属为优势类群;变形菌门、γ-变形菌纲、肠杆菌目、肠杆菌科、拉乌尔菌属在两者中都为优势类群。两者肠道细菌群落最显著的差异在于,取食洋白蜡幼虫链球菌科、乳球菌属相对丰度显著高于取食旱柳的幼虫,而肠球菌科、肠球菌属相对丰度显著低于取食旱柳的幼虫。直接取食洋白蜡枝干的幼虫肠道纤维素降解细菌种类丰富,隶属于4门、5纲、5目、7科、7属,15种;优势属包括微杆菌属、纤维单胞菌属、假单胞菌属;其中纤维素降解能力最强的4个菌株分别为2株假单胞菌和2株产黄纤维单胞菌;二者在滤纸复筛试验中显著地分解了滤纸,进一步验证了其良好的纤维素降解能力。【结论】在取食洋白蜡光肩星天牛幼虫肠道中,链球菌科、乳球菌属为优势类群,可能发挥重要功能但不直接降解纤维素;放线菌门下的微杆菌属、纤维单胞菌属和变形菌门下的假单胞菌属非优势类群但纤维素降解能力强,可能发挥降解纤维素的功能;上述菌群共存于光肩星天牛肠道,参与其适应洋白蜡的过程。【Objective】This study aims to explore the adaptive reasons of Anoplophora glabripennis larvae to Fraxinus pennsylvanica,a traditional resistant species,in terms of intestinal bacteria diversity.【Method】The A.glabripennis larvae were fed with F.pennsylvanica and Salix matsudana,respectively,and the high-throughput sequencing technology was used to sequence 16S rDNA of the larvae intestinal bacteria,with which the molecular identification and diversity analysis of intestinal bacteria were conducted.Subsequently,through accumulation culture,31 strains of cellulose-degrading bacteria were screened out from unfed larvae.The cellulose-degrading ability of each strain was determined by the transparent circle diameter(D)/colony diameter(D)as the standard,and the filter paper re-screening test was conducted on the four strains with the strongest cellulose-degrading ability.【Result】The results showed that Phylum Firmicutes,Class Bacilli,Order Lactobacillales,Family Streptococcaceae and the genus Lactococcus were predominant in the larvae intestinal tract after being fed with F.pennsylvanica.Whereas Phylum Firmicutes,Class Bacillus,Order Lactobacillales,Family Enterococcaceae and the genus Enterococcus were predominant in the larvae intestinal tract after being fed with S.matsudana.Phylum Proteobacteria,Class Gammaproteobacteria,Order Enterobacteriales,Family Enterobacteriaceae and the genus Raoultella were predominant in the both feedings.The most significant difference between the two groups was that the relative abundance of Family Streptococcaceae and genus Lactococcus in the larvae feeding on F.pennsylvanica was significantly higher than that in the larvae feeding on S.matsudana,while the relative abundance of Family Enterococcaceae and genus Enterococcus was significantly lower than that in the larvae feeding on S.matsudana.In the intestinal bacterial community of larvae feeding directly on the branch of F.pennsylvanica,there were abundant species of cellulose-degrading bacteria,belonging to 4 phyla,5 clas

关 键 词：16S rDNA 光肩星天牛 洋白蜡 旱柳 肠道细菌 纤维素降解细菌 

分 类 号：S763.38[农业科学—森林保护学]