中文摘要：

首次对采自额尔齐斯河北极茴鱼鳃部北方四钩虫（Tetraonchus borealis）的部分rDNA基因进行了PCR扩增、序列测定分析。结果显示,北方四钩虫28S和ITS1rDNA基因序列大小分别为332bp和513bp。利用MEGA 4.0程序的NJ法构建北方四钩虫28S及ITS1rDNA基因的系统进化树,结果显示北方四钩虫与同属的单肠四钩虫聚为一支,其支持率分别为83%和87%,为进一步研究四钩虫属虫种提供了分子生物学方面的资料。

英文摘要：

The 28 S and ITS1 ribosome ribonucleic acid（rDNA） of Tetraonchus borealis were amplified by PCR,sequenced and analyzed. The results showed that the 28 S and ITS1 rDNA were 332 bp and 513 bp in length, respectively. Phylogenetic trees constructed using MEGA version 4.0 （N J） indicated that T. bo- realis was genetically closer to T. rnonenteron,and the popularity rating were 83% and 87%,which will provide molecular biology information for Tetraonchus spp. studies.