Three-Dimensional Reconstruction Of The Galleries Of Several Wood Borer Species

Wood borers,numerous in species and distribution,Iead a covert life,damaging trunk and branches of many trees species.The adults and larvae could feed on both phloem and xylem of the trees,leaving the special damage traces-the gallery system.Those galleries vary following by the wood borer species.They are of significant impact on forestry,making the trees unhealthy or even to death.However,profound studies of the wood borer galleries have been rare currently.In this study,the galleries of the wood borers among several species were first studied.Combined with the biological characteristics,the complete galleries were chosen to quantitative shape analyze,explore the regularities and complete the three dimension reconstructions.In our research,the size and the shape of the galleries were analyzed using the geometric morphometries.The outline of the gallery was drawn,and the three dimension reconstructions of the galleries were completed.The main results were as follows(1)For the first time,the regulations of the parent galleries of several bark beetles were studied with the geometric morphometries methods:generally,the intraspecific parent galleries of the bark beetles had obvious regularity.The parent galleries of Scolytus jacobsoni Spessivtseff,Scolytus amurensis Eggers,Scolytus seulens!s Musayawa,Phloeosinus sinensis Schedle and Phloeosinus aubei Perris distributed vertically;whereas the parent galleries of Hylesinus laticollis Blandford and Tomicus minor Hartig distributed horizontally.The significant differences in shape were found in the parent galleries of P.sinensis and T.minor relating with the difference of the diameters of the woods.The difference of the interspecific parent galleries of the bark beetles was not significant(S.amurensis and S.seulensis)However,significant differences in other interspecific parent galleries of the bark beetles were found(P.s.inensis and S.amurensis,P.sinensis and S.seulensis)(2)Galleries of different wood borer species were divided into three types,the three-dimensional reconstruction and animation design of the galleries were completed:according to the damaged location of the xylem,the galleries of the wood borers were divided into surface damage type,internal damage type and damage from surface to interior type.Based on the analysis of the gallery,three dimension reconstructions of the galleries of seven species in Scolytidae only damaging the surface of the xylem,and the galleries that distributing on the surface of the xylem,damaging by eleven species in Cerambycidae,Buprestidae and Curculionidae,were completed.Based on the structures of the galleries,digital camera and software recognition,the three-dimensional reconstruction and animation design of the galleries distributed in the interior of the xylem were completed.We included the galleries of some species in Siricidae and Xyleborus only damaging the interior of the xylem,and the galleries distributing in the interior of the xylem which were damaged by some species in Cerambycidae.(3)Combined with biological characteristics,the morphological characteristics and the damage features of Agrilus subrobustus Saunders were observed detailed:The larvae of A.subrobustus were ivory colored and slender.Pupae were of the exarate type and adults were shiny and greenish.Features of adult morphology,including the shape(length versus width)of the pronotum,pronotum disk,prehumerus,metasternal projection,elytra pubescence distribution,and aedeagus,were described.The scientific name was clarified through detailed morphological comparisons and consultation of the literature.A.subrobustus damaged both the phloem and xylem of Albizia julibrislin Durazz,and was active on the sunny side of host trees.A.subrobustus bored galleries under the bark of its host,with round shaped entrance holes measuring less than 1 mm.Pupal chambers were oval shaped and mostly distributed in the xylem of the host with a minority in the phloem.Emergence holes were "D" shaped.Generally galleries could be divided into three types on the basis of morphological characters:a "Z"shaped or extende type,a vertically rounded type,and an ellipse or semicircular type.(4)Based on the three-dimensional reconstructions of the galleries,the relationships between the biological characteristics and the gallery systen of several species of wood borers were summarized:in our study,the family Scolytidae,Cerambycidae,Buprestidae,Siricidae Curculionidae and Bostrychidae were included.The similarities and differences of the wood borers in the same genus or family were summarized detailedly.The galleries of most species in Scolytidae distributed on the surface of the xylem,the galleries of some species in family Cerambycidae,Buprestidae and Curculionidae distributed on the surface and in the interior of the xylem.The galleries of some species in Siricidae and Xyleborus only damaged the interior of the xylem.The galleries of most species in Scolytidae had a very significant regularity and could reflect the biological and ecological characteristics.Compared with the galleries of some species in family Buprestidae and Siricidae,the galleries of Cerambycidae were coarser and longer.The galleries distributed on the surface of the xylem were flat,flaky and irregular The galleries distributed in the xylem were varied with species.The galleries of Curculionidae varied along with different species.The galleries of Bostrychidae distributed densely,the galleries of Sirex noctilio Fabricius had two types,the "L" and "U" shaped,the galleries of Sirex nitobei Matsumura had an "L" shaped.In this research,three dimension images of the gallery were reconstructed,which would promote the teaching informationalization.Besides,the explication of the relationship between the taxonomic category and the gallery system of the wood borers would help with the identification and the assessment of the damaging extent.According to the trend of the occurrence and development of the gallery system,the natural mortality rate of the larvae or the pupae could be estimated,and the guidance and suggestions for monitoring and preventing damage could be provided.