马尾松萎蔫病树一种线虫分离物的鉴定

Identification of a nematode isolate from wilt Pinus massoniana

2002年从贵阳市南明区采集到濒临死亡的马尾松标样,用改进的浅盘分离法对其进行了病原物的分离、纯化、形态学及分子生物学鉴定。结果表明,萎蔫死亡松树分离出的线虫形态特征与Mamiya报道的拟松材线虫形态特征相符。用伞滑刃线虫ITS区(internal transcribed spacer)通用引物VRF1(5′CGTAACAAGGTAGCTGTAG 3′)和VRF2(5′TC-CTCCGCTAAATGATATG 3′)对其基因组DNA进行PCR扩增,并对其PCR产物进行回收、克隆和测序。测序结果显示,此ITS序列与南京松材线虫的同源性为77.6％,与基因库已报道拟松材线虫序列U93554的同源性为93.5％,而与云南拟松材线虫江川种群、峨山种群和西畴种群的同源性为97.9％。通过以上形态学和分子生物学的研究,将贵阳市南明区采集到的马尾松萎蔫病树线虫分离物鉴定为拟松材线虫(Bursaphelenchus mucronatus)。

Wilt pine samples were collected from Guiyang in 2002. Morphological and molecular identification of the nematode which isolated and purified from the sample were carried out. The morphological identification showed that characteristics of the nematode was similar to what Mamiya reported. Poly-merase Chain Reaction ( PCR) amplification of the internal transcribed spacer (ITS) of the ribosomal DNA of the samples was done with universal primers VRFK5'CGTAACAAGGTAGCTGTAG 3') and VRF2 (5' TCCTCCGCTAAATGATATG 3'), and the PCR products were cloned into pGEM-T vector. Sequencing results showed that the homology between the samples and Bursaphelenchus xylophilus (Nanjing) was 77. 6%, and shared 93. 5% and 97. 9% homology with U93554 (B. mucronatus sequence in GenBank) and 3 populations of B. mucronatus isolated from Yunnan, respectively. The results revealed that the nematode isolate from Guiyang was B. mucronatus.