Preliminary Study On Phylogeny Of Dacnusini Of China(Hymenoptera:Braconidae) Based On The 28S RDNA D2 Sequence And Morphological Characters

Dacnusini was the genus in Alysiinae(Hymenoptera Braconidae)sand the major part was parasitic wasp for Agromyzidae insects.Dacnusini were widely distributed,playing an important role in pest bio-control.However,the research on the classification of Dacnusini is limited to classify by traditional morphological character.Based on the principles and methods of cladistics,the article made an analysis of Dacnusini’s 64 species in 8 genera,including morphological characteristics,molecular identification and phylogenic study,aimed to make clear the relations between genera and species of Dacnusini.Based on the morphological characteristics of Dacnusini,81 characteristics are adopted to build a morphological matrix to make a cladistic analysis.Opius caricivorae of Opiinae Cresson as an outgroup,using the method of lossless extraction of DNA,according to the fragment and morphological characteristics of 28Sr DNA D2 and the data collection of morphological matrix from 28Sr DNA D2,ML,MP,NJ were used to construct a phylogenetic tree and analyze the phylogeny.The results are as follows:The cladistic analysis based on the 81 morphological characteristics of Dacnusini showed that the relation among the 8 genera of Dacnusini is:Amyras+((Polemochartus+(Cheanusa+(Trachionus+Coelinidea)))+((Da cnusa+Exotela)+Chorebus))).The D2 fragment of 28 S rDNA is applied to the phylogenic study of Dacnusini’s 64 species under 8 genera.The article designs specific primers of the D2 fragment of 28 S rDNA of Dacnusini because some individuals are not available in the enlargement of general primers.In the 28SrDNA D2 sequence was 218 conserved sites,which was 60.1%of the total number of sequence;142variable sites,accounting for 39.1%of the total locus;68 parsimony informativesites,18.7%Of the whole sequence,74 singleton sites,accounting for 20.4%of the total sequence.27 transitionsal pairs,17 transversional pairs.GC content is 45.2%.The conversion of the base occurs mainly between the TCs.the D2 fragment of 28S rDNA of Dacnusini is highly conserved.The phylogenetic tree of 3 method was a slight difference.The phylogenetic analysis shows that Chorebus is a monophyletic group,Phaenolexis is the sister to Chorebus;Coelinidea,Polemochartus and Cheanusa form a moniphyletic group;but Dacnusa is a paraphyletic group.the relationship of Trachionus is far from other generas.The comprehensive analysis showed that there are some differences among Dacnusini’s morphological tree,molecule tree and the mixed data tree of morphology and molecule.The 28 S rDNA D2 sequence should be used carefully to discuss the relations of Dacnusini’s species.All three trees indicate that Dacnusa is not a monophyletic group,but is a paraphyletic group.Dacnusa(Dacnusa)is better to be a new genus;Coelinidea and Chorebus were monophyletic group,and Coelinidea and Polemochartus are two sister groups.The experiment is based on the morphological characteristics and molecular data and provides some evidence for the research on the phylogeny of Dacnusini,having an important effect on the selection,protection and using of resources of Dacnusini.