摘要
The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellaeand N. melleni are obtained by polymerase chain reaction (PCR) amplified using a couple of special primers andthen sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varying in 337bp accounting for 0.3% genetic difference, from the relative species N. girellae and N. melleni parasitized on thedifferent fishes in different farms displays that they possess a very high genetic similarity of 99.7%, higher thanthat of 99.41% for the single species N. melleni sampled in different areas, and the intraspecific divergence of N.melleni is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e., B. lutjani, B. rohdei and B. seriolae) range from 2.08% to11.73%. In addition, UPGMA and MP molecularphylogenetic trees are constructed and proved to be consistent with each other. Though the morphologicalcharacteristics and the results of genetic diversity for the two Neobenedenia show a high similarity, whether theybelong to a single species or not are still undefined, and the more genes of them should be further investigated, incombination with the systematical and detailed morphological study.
The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellaeand N. melleni are obtained by polymerase chain reaction (PCR) amplified using a couple of special primers andthen sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varying in 337bp accounting for 0.3% genetic difference, from the relative species N. girellae and N. melleni parasitized on thedifferent fishes in different farms displays that they possess a very high genetic similarity of 99.7%, higher thanthat of 99.41% for the single species N. melleni sampled in different areas, and the intraspecific divergence of N.melleni is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e., B. lutjani, B. rohdei and B. seriolae) range from 2.08% to11.73%. In addition, UPGMA and MP molecularphylogenetic trees are constructed and proved to be consistent with each other. Though the morphologicalcharacteristics and the results of genetic diversity for the two Neobenedenia show a high similarity, whether theybelong to a single species or not are still undefined, and the more genes of them should be further investigated, incombination with the systematical and detailed morphological study.
基金
This study was supported by both grants from the National“863"Development Project of China under contract No.2002AA603021
the Science and Technology Depatment of Fujian Province.
