Study On The Wood Identification Of Five Species Of Phoehe Spp. And Machilus Spp. Based On The DNA-barcodes Technology

The anatomical features of the Phoehe spp.and Machilus spp.wood are considerably similar,as well as the certain species of the same genus.The species of the two genera can be hardly identified by the traditional approaches of the wood anatomy.The DNA(Deoxyribonucleic acid)barcodes technology was used to identify the wood of the Phoehe spp.and Machilus spp.in this study.The wood of Phoehe boumei,Phoehe zhennan,Phoehe sheareri,Machilus oreophila andMachilus pauhoi were taken as.the research objects,of which the macro-structure and micro-structure were explored.Furthermore,the DNA was extracted from fresh leaves,fresh timbers and the timbers dried at the different temperature using the DNeasy(?)Plant Mini Kit,CTAB-NuClean PlantGen DNA Kit and SDS-CTAB-NuClean PlantGen DNA Kit,and then,the DNA barcode of matK,trnL-trnF,trnL-intro,ycf3,psbC-trnS,ITS,rpoB and rpoCl were amplified by PCR(Polymerase Chain Reaction).The results of this study are showed as follows:Firstly,the identification characteristics of the five species are as follows.Wood diffuse-porous,solitary vessel or vessels in radial multiples of two-to-four,simple perforation plates and few multiple perforation plates,intervessel pits alternate.Axial parenchyma mainly vasicentric,septate fibres present.Rays non-storied,Kribs heterogeneous Ⅱ and Ⅲ.Oil and mucilage cells abundant.The three species of Phoehe spp.and the two species of Machilus spp.have a quite similar wood structure.Secondly,the samples were dried at 30℃,70℃and 105℃,and the result indicated that a high temperature could cause a higher degradation degree.Consequently,the concentration of DNA concentration extracted from the timber was lower.Both the quantity and quality of DNA extracted from the dried timbers by the DNeasy(?)Plant Mini Kit,CTAB-NuClean PlantGen DNA Kit and SDS-CTAB-NuClean PlantGen DNA Kit could meet the need of the PCR amplification.Thirdly,the results from the analysis of the DNA sequences indicated that the wood of Phoehe spp.and Machilus spp.could be differentiated by the gene fragment of trnL-trnF,ITSand rpoB,Machilus oreophila and Machilus pauhoi could be differentiated by the gene fragment of matK and trnL-intro,and the wood of Phoehe zhennan,Machilus oreophila and Machilus pauhoi could be differentiated by the gene fragment of ycf3.The Phoehe sheareri wood could be identified solely by the gene fragment of psbC-trnS,and the gene fragment of rpoC1 showed no sequence variations among the five species.Thus,all the five species of wood samples could be identified in sequence combined withthe gene fragment of ycf3 and psbC-trnS.Finally,the wood of Phoehe boumei,Phoehe zhennan,Phoehe sheareri,Machilus oreophila andMachilus pauhoi are distinguished accurately by the DNA barcodes technology successfully,and the DNA barcodes that can distinguish the five species are found out,which provides scientific and accurate approaches for the wood identification of the Phoehe spp.and Machilus spp.wood.