Hybridization of the marine seaweeds, Fucus serratus and Fucus evanescens (Heterokontophyta: Phaeophyceae) in a 100-year-old zone of secondary contact
Hybridization of the marine seaweeds, Fucus serratus and Fucus evanescens (Heterokontophyta: Phaeophyceae) in a 100-year-old zone of secondary contact
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DOI：
10.1098/rspb.2002.2093
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发表时间：
2002-09-07
影响因子：
4.7
通讯作者：
Olsen, JL
中科院分区：
文献类型：
--
作者：
Coyer, JA;Peters, AF;Olsen, JL
历史上，潮间带海藻墨角藻（Fs）和墨角藻evanescens（Fe）仅沿着挪威西海岸同域分布。在19世纪90年代中期，铁（雌雄同株）被意外引入奥斯陆峡湾。假定的杂交与特有的Fs（雌雄异株）观察到在奥斯陆峡湾1977年，在卡特加特海峡和波罗的海西部的1998年。在丹麦的Blushoj（卡特加特海），只有当Fe和Fs的密度分别超过14和2 m（-2）时，才存在推定的Fs x Fe混合物。1999年收集的所有58个假定的杂种都是雌雄异株的，在形态上是中间的。基本上所有的（57的58）是生殖成熟，但卵原细胞拥有更少和更多的卵比父母。检查每个亲本物种和假定的杂交细胞核，线粒体和叶绿体分子标记证实了杂交的发生。此外，所有的杂种都具有Fe型叶绿体和线粒体，表明只有Fe卵× Fs精子配对在田间是成功的。F卵X Fe精子的相互交叉是不存在的领域和显着不太成功的实验室杂交。不对称杂交也被报道用于几种植物和动物。
Historically, the intertidal seaweeds Fucus serratus (Fs) and Fucus evanescens (Fe) were sympatric only along the western coast of Norway. In the mid-1890s, Fe (monoecious) was accidentally introduced into the Oslofjord. Putative hybridization with the endemic Fs (dioecious) was observed in Oslofjord by 1977 and in the Kattegat and western Baltic Seas by 1998. At Blushoj, Denmark (Kattegat Sea) putative Fs x Fe hybrids were present only when densities of Fe and Fs exceeded 14 and 2 m(-2), respectively. All of the 58 putative hybrids that were collected in 1999 were dioecious and intermediate in morphology. Essentially all (57 out of 58) were reproductively mature, but the oogonia possessed fewer and more variably sized eggs than either parent. Examination of each parental species and putative hybrids with nuclear, mitochondrial and chloroplast molecular markers confirmed the occurrence of hybridization. Furthermore, all of the hybrids possessed Fe-type chloroplasts and mitochondria, indicating that only the Fe egg x Fs sperm pairing was successful in the field. The reciprocal cross of Fs egg x Fe sperm was absent in the field and significantly less successful in laboratory crossings. Asymmetrical hybridization has also been reported for several species of plants and animals.