Who's your mama? Riverine hybridisation of threatened freshwater Trout Cod and Murray Cod
Who's your mama? Riverine hybridisation of threatened freshwater Trout Cod and Murray Cod
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DOI：
10.7717/peerj.2593
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发表时间：
2016-10-27
期刊：
影响因子：
2.7
通讯作者：
Lintermans, Mark
中科院分区：
文献类型：
--
作者：
Couch, Alan J.;Unmack, Peter J.;Lintermans, Mark
由于易位、生物的重新放养和生境的改变，杂交和渐渗的速率在世界范围内急剧增加;因此，确定在重新引入灭绝的同类物种后是否发生杂交对于保护至关重要。放养计划有时受到批评，因为孵化场繁殖的鱼类与野生种群繁殖的遗传后果。这些问题对保护恢复计划很重要，包括来自澳大利亚淡水鱼科的鱼。澳大利亚的Percichthyidae中有两种比较有名的是Murray Cod，Maccullochella peelii和Trout Cod，Maccullochella macquariensis，它们以前广泛分布在墨累达令盆地（Murray Darling Basin）。在Mtirrrumbidgee河的大部分地区，鳟鱼鳕鱼和默里鳕鱼都是本地的，直到20世纪70年代末鳟鱼鳕鱼被灭绝。在这里，我们使用遗传单核苷酸多态性（SNP）的数据与线粒体序列一起检查杂交和渗入之间的墨累鳕鱼和鳟鱼鳕鱼在上Murrumbidgee河，并考虑对放养计划的影响。我们已经确认重新放养的河鳟鱼鳕鱼繁殖，但只作为种间交配，在野外。我们发现杂交鳟鱼鳕鱼默里鳕鱼上Murrumbidgee，记录在野外的第一个杂交幼虫。虽然杂交幼虫，青少年和成人已记录在孵化场和蓄水池，并混合成人已记录在河流中以前，这是第一次肥沃的F1已记录在野生河流人口。F1与墨累鳕鱼的回交也被发现是可育的。所有回交注意到纯穆雷鳕鱼。这种基因渗入以前没有记录在这两个物种，杂交方向的不平衡可能有重要的意义，为放养计划。
Rates of hybridization and introgression are increasing dramatically worldwide because of translocations, restocking of organisms and habitat modifications; thus, determining whether hybridization is occuring after reintroducing extirpated congeneric species is commensurately important for conservation. Restocking programs are sometimes criticized because of the genetic consequences of hatchery-bred fish breeding with wild populations. These concerns are important to conservation restocking programs, including those from the Australian freshwater fish family, Percichthyidae. Two of the better known Australian Percichthyidae are the Murray Cod, Maccullochella peelii and Trout Cod, Maccullochella macquariensis which were formerly widespread over the Murray Darling Basin. In much of the Mtirrumbidgee River, Trout Cod and Murray Cod were syrnpatric until the late 1970s when Trout Cod were extirpated. Here we use genetic single nucleotide polymorphism (SNP) data together with mitochondrial sequences to examine hybridization and introgression between Murray Cod and Trout Cod in the upper Murrumbidgee River and consider implications for restocking programs. We have confirmed restocked riverine Trout Cod reproducing, but only as inter-specific matings, in the wild. We detected hybrid Trout Cod Murray Cod in the Upper Murrumbidgee, recording the first hybrid larvae in the wild. Although hybrid larvae, juveniles and adults have been recorded in hatcheries and impoundments, and hybrid adults have been recorded in rivers previously, this is the first time fertile F1 have been recorded in a wild riverine population. The F1 backcrosses with Murray cod have also been found to be fertile. All backcrosses noted were with pure Murray Cod. Such introgression has not been recorded previously in these two species, and the imbalance in hybridization direction may have important implications for restocking programs.