Cradle for the newborn Monochamus saltuarius:Microbial associates to ward off entomopathogens and disarm plant defense  

作　　者：Si-Xun Ge Jia-Xing Li Zhuo-Heng Jiang Shi-Xiang Zong Li-Li Ren 

机构地区：[1]Bejing Key Laboratory for Forest Pest Control,Bejing Forestry University,Beijing,China [2]School of Science,Westlake University,Hangzhou,China [3]Sino-French Joint Laboratory for Invasive Forest Pests in Eurasia,Bejing Forestry University-French National Research Institute for Agriculture,Food and Environment(INRAE),Bejing,China

出　　处：《Insect Science》2023年第4期1165-1182,共18页昆虫科学（英文版）

基　　金：supported jointly by the National Key R&D Program of China(2021YFD1400900);Beijing's Science and Technology Planning Project"Z201100008020001."。

摘　　要：The Japanese pine sawyer,Monochamus saltuarius,as a beetle vector of Bur-saphelenchus xylophilus(pine wood nematode),is an economically important forest pest in Eurasia.To feed on the phloem and xylem of conifers,M.saltuarius needs to overcome various stress factors,including coping with entomopathogenic bacteria and also various plant secondary compounds(PSCs).As an important adaptation strategy to colonize host trees,M.saltuarius deposit eggs in oviposition pits to shield their progeny.These pits har-bor bacterial communities that are involved in the host adaptation of M.saltuarius to the conifers.However,the composition,origin,and functions of these oviposition pit bacteria are rarely understood.In this study,we investigated the bacterial community associated with M.saltuarius oviposition pits and their ability to degrade PSCs.Results showed that the bacterial community structure of M.saltuarius oviposition pits significantly differed from that of uninfected phloem.Also,the oviposition pit bacteria were predicted to be enriched in PSC degradation pathways.The microbial community also harbored a lethal strain of Serratia,which was significantly inhibited.Meanwhile,metatranscriptome anal-ysis indicated that genes involved in PSCs degradation were expressed complementarily among the microbial communities of oviposition pits and secretions.In vitro degrada-tion showed that bacteria cultured from oviposition pits degraded more monoterpenes and flavonoids than bacteria cultured from uninfected phloem isolates.Disinfection of ovipo-sition pits increased the mortality of newly hatched larvae and resulted in a significant decrease in body weight in the early stages.Overall,our results reveal that M.saltuarius construct oviposition pits that harbor a diverse microbial community,with stronger PSCs degradation abilities and a low abundance of entomopathogenic bacteria,resulting in the increased fitness of newly hatched larvae.

关 键 词：community structure entomopathogenic bacteria host plant adaptation plant secondary metabolites symbiotic bacteria 

分 类 号：Q96[生物学—昆虫学]