Weinert Lucy A, Tinsley Matthew C, Temperley Matilda, Jiggins Francis M
Institute of Evolutionary Biology, University of Edinburgh, Edinburgh EH9 3JT, UK.
Biol Lett. 2007 Dec 22;3(6):678-81. doi: 10.1098/rsbl.2007.0373.
Vertically transmitted bacterial symbionts are common in arthropods. However, estimates of their incidence and diversity are based on studies that test for a single bacterial genus and often only include small samples of each host species. Focussing on ladybird beetles, we collected large samples from 21 species and tested them for four different bacterial symbionts. Over half the species were infected, and there were often multiple symbionts in the same population. In most cases, more females than males were infected, suggesting that the symbionts may be sex ratio distorters. Many of these infections would have been missed in previous studies as they only infect a small proportion of the population. Furthermore, 11 out of the 17 symbionts discovered by us were either in the genus Rickettsia or Spiroplasma, which are rarely sampled. Our results suggest that the true incidence and diversity of bacterial symbionts in insects may be far greater than previously thought.
垂直传播的细菌共生体在节肢动物中很常见。然而，对它们的发生率和多样性的估计是基于检测单一细菌属的研究，而且通常只包括每个宿主物种的小样本。以瓢虫为例，我们从21个物种中收集了大量样本，并对它们进行了四种不同细菌共生体的检测。超过一半的物种受到感染，并且在同一群体中通常存在多种共生体。在大多数情况下，感染的雌性比雄性多，这表明共生体可能是性别比例扭曲者。在以前的研究中，许多这些感染可能会被遗漏，因为它们只感染了一小部分群体。此外，我们发现的17种共生体中有11种要么属于立克次氏体属，要么属于螺旋体属，而这两种属很少被采样。我们的结果表明，昆虫中细菌共生体的真实发生率和多样性可能比以前认为的要高得多。
