A Comparative Study On Isoezyme Of 10 Kinds Of Bark Beetle

EST isoenzymes, POD isoenzymes, MDH isoenzymes in ten species of bark beetle, Phloeosinus aubei Perris, Cryphlus tabulaeformis chienzhuangensis Tsai et Li, Scolytus ratzeburgi Janson, Blatophagus piniperda Linnaeus, Ips sexdentatus Boerner, I. acuminatus Gyllenhal, I. duplicatus Sahalberg, I. mannsfeldi Wachtl, I. subelongatue Motschulsky, I. typographus Linnaeus, were studied by the vertical slab polycrylamide gel electrophoretic (PAGE).The result showed that EST isoenzymes bands were clear, variform and stable. There were enzyme bands with identical and distenct Rf which could be used to distinguish the bark beetle species excepting the larvae and adult of Cryphlus tabulaeformis chienzhuangensis Tsai et Li. It was showed that there was same characteristic band between larvae and adult within a species. The number of enzyme band of larvae was more than that of adult and EST isoenzymes in larvae stage was more active than that in adult stage. The difference of EST isoenzymes in the band number, relative mobility, staining intensity and band breadth among genera was greater than that among species within a genus. Six species of Ips had some enzyme bands with the similar Rf value and also there were some remarkable distinct bands among the species. Clustering analysis proved that six species in Ips genus had close relationship and the dendrogram implicated a phylogenetic relationship of the ten species.POD isoenzymes band was stable less, fewer numbers and less active compared with the bands of EST isoenzymes. The larvae of Ph. aubei Perris, I. acuminatus Gyllenhal and the adult of C. tabulaeformis chienzhuangensis Tsai et Li had no POD isoenzymes band. The other seven species had POD isoenzymes bands, but there were less similar bands between the larvae and adult in a species. The difference of POD isoenzymes in the band number, relative mobility, staining intensity and band breadth among genera was greater than that among species. POD isoenzymes band of I.duplicatus Sahalberg and I. mannsfeldi Wachtl was almost same, so it was difficult to be used to distinguish the species.The band of MDH isoenzymes was neither clear nor stable and the number was less than that of EST isoenzymes or POD isoenzymes. The difference among genera was significant, but not among species within a genus.