کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5744180 | 1618111 | 2017 | 8 صفحه PDF | دانلود رایگان |

- We report two populations of Aporrectodea trapezoides with co-occurrence of sexual and parthenogenetic individuals.
- We studied their population structure with the aim of understanding the origins of parthenogenesis in earthworms.
- In all cases sexual and parthenogenetic earthworms from each locality shared mitochondrial and nuclear sequence types.
- All the analyses supported the existence of strong genetic structure at the level of locality but not due to reproductive mode providing evidence of multiple recent origins of parthenogenesis in this species.
Little is known about the origin and spatial pattern of the common phenomenon of parthenogenesis in earthworms. Aporrectodea trapezoides is unique in having a global distribution, where asexual forms are broadly known. Here we report two populations in Plasencia (Spain) and Karkra (Algeria) with multiple instances of co-occurrence of sexual and parthenogenetic individuals. We thus studied these populations where the two stages coexist with the aim of understanding the origins of parthenogenesis in earthworms. Two mitochondrial (COII and 16S rRNA) and three nuclear (ITS2, histone H3 and 28S rRNA) genes where evaluated to shed light on the mode, timing and frequency of origin of parthenogenetic forms. A population genetic study showed that in all cases sexual and parthenogenetic earthworms shared mitochondrial and nuclear sequence types, and that there is a strong genetic structure at the geographic level. Genetic divergence in both mitochondrial genes was high (up to 9.61% in COII and 6.12% in 16S rRNA), and ITS2 sequences were identical in individuals from closely related localities within a population. The haplotype networks, AMOVAs, Mantel tests and FST values all support the existence of strong genetic structure at the level of locality, but not due to reproductive mode, therefore providing evidence of multiple recent origins of parthenogenesis in this species.
Journal: European Journal of Soil Biology - Volume 81, JulyâAugust 2017, Pages 31-38