Center for Medical, Agricultural and Veterinary Entomology, United States Department of Agriculture-Agricultural Research Service, Gainesville, Florida, United States of America.
PLoS One. 2022 Nov 11;17(11):e0277510. doi: 10.1371/journal.pone.0277510. eCollection 2022.
The threat of invasive species is increasing with the expansion of global trade and habitat disruption. A recent example is the establishment of fall armyworm (FAW), a noctuid moth native to the Americas, into most of the Eastern Hemisphere with projections of significant economic losses on a global scale. The species has traditionally been subdivided into two populations that differ in their propensity to use different plant hosts, a phenotype with clear relevance for identifying crops at risk. However, inconsistencies in the genetic and phenotypic descriptions of these "host strains" has led to controversy about their composition and even existence. In this study, the locus for the Triosephosphate isomerase gene (Tpi) is used both as a host strain marker and for phylogenetic analysis. Association of the host choice phenotype with the Tpi-derived phylogenetic tree uncovered genetic differentiation between populations that supports the existence of the host strains and provided evidence that they are subject to different selection pressures. This correspondence of differential host use with Tpi was demonstrated for populations from a broad geographical range and supports the involvement of one or more Z-chromosome functions controlling the phenotype. Comparisons of collections from multiple locations identified significant differences in the efficacy of different molecular markers that implicate regional variations in host strain behavior.
随着全球贸易的扩大和生境的破坏，入侵物种的威胁日益增加。最近的一个例子是秋黏虫（FAW）的建立，秋黏虫是一种原产于美洲的夜蛾，现已进入东半球的大部分地区，预计会在全球范围内造成重大经济损失。该物种传统上被分为两个种群，它们在利用不同植物宿主的倾向方面存在差异，这种表型对于识别处于风险中的作物具有明显的相关性。然而，这些“宿主株系”的遗传和表型描述的不一致性导致了关于它们的组成甚至存在的争议。在这项研究中，三磷酸甘油醛异构酶基因（Tpi）的基因座既被用作宿主株系标记，也被用于系统发育分析。宿主选择表型与 Tpi 衍生的系统发育树的关联揭示了种群之间的遗传分化，支持宿主株系的存在，并提供了证据表明它们受到不同选择压力的影响。这种与 Tpi 相关的不同宿主利用的相关性在广泛地理范围内的种群中得到了证明，并支持一个或多个 Z 染色体功能控制表型的参与。对来自多个地点的收集物的比较确定了不同分子标记的有效性存在显著差异，这表明宿主株系行为存在区域性差异。
