翅荚木解剖构造特征及DNA条形码识别研究

Sudy on the Anatomical Structural Characteristics and DNA Barcode Identification of Zenia insignis

以翅荚木标本为研究材料,利用显微技术对其宏观构造及微观构造进行观察和分析;并以翅荚木9年生新鲜材作为对照组,对两者的DNA序列进行比对分析,分别对2个木材样品的trnL、rbcL和psbA-trnH 3段DNA序列进行PCR扩增,并对PCR产物进行测序和序列比对。结果表明:翅荚木为散孔材,生长轮明显;单管孔或少数径列复管孔(2~4个),穿孔板为单穿孔,具多角形互列管间纹孔式,导管-射线间纹孔式同管间纹孔式;射线组织主为异Ⅲ型,稀异Ⅱ型。CTAB试剂盒法,能够成功提取满足PCR扩增需求的翅荚木新鲜组织及标本的DNA。2个木材样品的3段DNA序列均能与NCBI系统中翅荚木100%匹配,其中psbA-trnH序列能与其他树种区分开,有较高的分辨率,可作为翅荚木分子鉴定的备选条形码,从3段序列构建的系统发育树来看,几个树种可以被正确聚类。

The specimen of Zenia insignis were taken as the research material,the macrostructure and microstructure were observed and analyzed by microtechnology;the 9 years fresh wood of Z.insignis was used as the control group to compare and analyze their DNA sequences,3 DNA section of trnL,rbcL and psbA-trnH DNA sequences of 2 wood samples were amplified by PCR,and the PCR products were sequenced and aligned.The results show that the wood of Z.insignis was diffuse-porous,the growth ring boundary was evident;the combination of pore was mainly solitary pores and radial multiple pores(2-4 cells),the perforation plates was simple perforation,the intervessel pitting was shape of alternate pits polygonal,vessel-ray pits are the same as the intervessel pitting;the ray types were heteromorphosis III and rare heteromorphosis II.The CTAB kit method could successfully extract DNA from fresh tissues and specimens of Z.insignis that met the requirements of PCR amplification.The 3 DNA sequences of the 2 wood samples could match 100%with Z.insignis of the NCBI system,and the psbA-trnH sequence could be distinguished from other tree species with high resolution,which could be used as an alternative barcode for molecular identification of Z.insignis.From the phylogenetic tree obtained by the NJ method based on 3 DNA sequences,several species could be clustered correctly.