Extremely divergent host plant acceptance with gene flow between sympatric host races of the phytophagous ladybird beetle Henosepilachna diekei
Extremely divergent host plant acceptance with gene flow between sympatric host races of the phytophagous ladybird beetle Henosepilachna diekei
复制标题
植食性瓢虫 Henosepilachna diekei 的同域宿主种族之间基因流的宿主植物接受度存在极大差异
DOI：
10.1111/ens.12382
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发表时间：
2019
影响因子：
0.9
通讯作者：
Katakura Haruo
中科院分区：
文献类型：
--
作者：
Matsubayashi Kei W.;Kahono Sih;Hartini Sri;Katakura Haruo
在没有其他形式的生殖隔离的情况下，仅生态分歧就可以阻止大多数基因流动。虽然生态分化在促进生殖隔离方面的重要性已被广泛认识到，但其对物种形成的净影响在野外很少被估计。植食性瓢虫Henosepallachna diekei Jadwitzczak&Wegrzynowicz包括两个共域寄主小种，它们仅通过对寄主植物薇甘菊(菊科)或Leucas lavandulifoliaSm的极端专化而被分离繁殖。(拉米科)产于印度尼西亚西爪哇。为了研究不同寄主作为隔离屏障的影响，我们利用13个寄主小种的野生种群，包括4个共面种群对，进行了基于线粒体ND2和核ITS2基因序列的成虫接受测试和分子种群遗传分析。这些寄主小种的几乎所有个体都坚持只接受原始寄主植物。我们检测到了这些寄主种族之间有限但一定程度的基因流动。与它们的分化时间相比，迁徙事件发生的时间很近，表明这些寄主小种在调查区域内最近发生了二次接触。这些结果揭示了寄主-植物转移对物种形成几乎整个过程的巨大影响，并说明即使在一定程度的基因流存在的情况下，生态差异仍然保持着。
Ecological divergence alone can prevent the majority of gene flow in the absence of other forms of reproductive isolation. Although the importance of ecological divergence in promoting reproductive isolation has been broadly recognized, its net impact on speciation has rarely been estimated in the wild. The phytophagous ladybird beetleHenosepilachna diekeiJadwiszczak & Wegrzynowicz includes two sympatric host races that are reproductively isolated solely by extreme specialization to either of the host plantsMikania micranthaKunth (Asteraceae) orLeucas lavandulifoliaSm. (Lamiaceae) in West Java, Indonesia. To investigate the impact of differential host use as an isolating barrier, we carried out adult host acceptance tests and molecular population genetic analyses based on mitochondrialND2and nucleicITS2gene sequences using 13 wild populations of the host races, including four sympatric population pairs. Almost all individuals of these host races persistently accepted only the original host plant. We detected restricted but a degree of gene flow between these host races. A migration event occurred only in very recent time compared to their divergence time, indicating recent secondary contact of these host races in the surveyed area. These results reveal the remarkably large impact of host‐plant shift over almost the entire process of speciation and illustrate that ecological divergence has been maintained even under the presence of a certain degree of gene flow.