Research Of Complete Mitochondrial Genome Of 3 Ips And Risk Analysis Of Invasive Species Of Ips

Ips spp.are a group of important global pest,which can infest bark and spread over a long distance by imported timber.Since the reform and open policy,the economic of China developed very fast,and a large amout of timber was needed expecially after implementing of natural forest protection project.Ips spp.were captured frequently in the imported timber,and their were important pests of port quarantine,which were listed as quarantine pest in the file of harmful organisms list for the plant importing quarantine of the People’s Republic of China,that was issued by China’s Ministry of Agriculture on May 28,2007.As an important kind of quarantine pest,their were necessary to carry out the research of phylogeny and risk analysis.In this study,the phylogeny of Ips spp.based on mitochondrial genome and mensurable risk analysis were carried out,the main research conclusions were as follows:1)The analysis of the incomplete mitochondrial genome of I,grandicollis,I.typographus and I.sexdentatus indicated that:The mt genomes of the three Ips species are 11,553 bp,13,135 bp and 13,502 bp,respectively;and contain 28 genes,30 genes and 30 genes,respectively.Their gene arrangements and directions are consistent with that of Drosophila yakuba.The three Ips species have the conservative sequences(ATGATAG)for Scolytinae between ATP8 and ATP6 genes;use the TTG as start codon for ND1 genes;use ATG as stop codon for ATP8 genes.All tRNAs genes could apparently fold into a typical cloverleaf structure except the tRNASer1.Three tRNASer1 genes lack the DHU arm and then form the D-loop.2)The phylogeny of Curculionidae based on 28 mitogenomes indicated that Scolytinae is not monophyly and belongs to Curculionidae.This result also shows that the phylogeny of Scolytids by using the mitochondrial genome was relatively reliable.(I.grandicollis of North America and I.typographus of Eurasia)and I.sexdentatus of Eurasia are sister groups,which indicates the Phylogenetic relationship of Ips species is not related with the geographical location.3)The phylogeny of Ips based on COI genes indicated that Ips is not monophyly and the classification and determination boundaries between Ips and Orthotomicsus need to be further explored.Moreover,the clustering structure of(Ips mexicanus + Ips concinnus)+ Pityogenes trepanatus + Ips calligraphus +(Ips + Orthotomicus)indicated that it is not possible to exclude the possibility of the relationship between Ips and Pityogenes trepanatus were similar to Orthotomicus and the phylogenetic relationship need to be further explored.4)The results of the analysis of intercepted pests in imported timber,2005～2015 years of China’s ports accumulated in the country from 145 countries and regions of the 580 million m3 timber intercepted pests in the 4266 species,780481batches;form 64 countries or regions intercepted invade Ips was 21 species,26237 batches.Among those 21 species,the frequency of intercepted non distributed species was from high to low:Ips grandicollis、Ips pini、Ips concinnus、Ips latidens、Ips calligraphus、Ips perturbatus、Ips paraconfusus、Ips confusus、Ips tridens、Ips borealis、Ips mexicanus、Ips amitinus、Ips montanus、Ips plasfographus;the frequency of intercepted distributed species was from high to low:Ips typographus、Ips subelongatus、Ips sexdentatus、Ips acuminatus、Ips duplicatus、Ips nitidus、Ips mannsfeldi.5)According to the results of SOM analysis,their primary invasion risk values range from 0.00018 to 0.81474,in which,that have been distributed in China with the highest primary risk values,the order was like this:Ips sexdentatus,I.typographus,I.duplicatus,I.subelongatus,I.acuminatus,I.nitidus,I.mannsfeldi;that have not been distributed in China,the order was like this:I.amitinus,I.concinnus,I.tridens,I.grandicollis,I.calligraphus,I.mexicanus,I.montanus,I.latidens,I.pini,I.confuses,I.perturbatus,I.paraconfusus,I.borealis,I.plasfographus.6)Potential suitable distribution in China of five main forgine Ips was predicted by using BIOCLIM ecological niche modeling of DIVA-GIS,they were I.typographus,I.grandicollis,I.pini,I.concinnus,I.calligraphus.The results show that areas suitable for the living of Ips wildely distributed in northeastern,central and southern of China.7)Based on invasive risk analysis of @Risk,we got these conclusions:the colonization and reproduction probability of five Ips spp.were obviously different.For I.typographus,the possibility of further spread was very high,which was 77.754%;for I.grandicollis,I.pini,I.concinnus and I.calligraphus,the colonization and reproduction possibility were 2.07%,0.305%,0.017%and 0.011%,respectively.The sensitivity analysis show that infection rate of timber and insect numberof unit volume were key factor of influence.8)The prediction results of the economic loss assessment models indicate that:the total value of potential economic losses for five insects were high.The total value of potential economic loss caused by I.typographus,I.grandicollis,I.pini,I.concinnus,I.calligraphus will be 1.8571～37.8203 billion Yuan,0.7294～23.5179 billion Yuan,0.05306～9.6222 billion Yuan and 0.4319～38.9277 billion Yuan,respectively.According to results of risk analysis,we put forward the corresponding risk management measures.