Table_1_Revisiting fall armyworm population movement in the United States and Canada.docx

IntroductionBiophysical approaches validated against haplotype and trap catch patterns have modeled the migratory trajectory of fall armyworms at a semi-continental scale, from their natal origins in Texas or Florida through much of the United States east of the Rocky Mountains. However, unexplained variation in the validation analysis was present, and misalignments between the simulated movement patterns of fall armyworm populations and the haplotype ratios at several locations, especially in the northeastern US and Canada, have been reported.
MethodsUsing an expanded dataset extending into Canada, we assess the consistency of haplotype patterns that relate overwintered origins of fall armyworm populations to hypothesized dispersal trajectories in North America and compare the geographic distribution of these patterns with previous model projections.
Results and discussionWe confirm the general accuracy of previous modeling efforts, except for late in the season where our data suggests a higher proportion of Texas populations invading the northeast, extending into eastern Canada. We delineate geographic limits to the range of both overwintering populations and show that substantial intermixing of the Texas and Florida migrants routinely occurs north of South Carolina. We discuss annual variation to these migratory trajectories and test the hypothesis that the Appalachian Mountains influence geographic patterns of haplotypes. We discuss how these results may limit gene flow between the Texas and Florida natal populations and limit the hereditary consequences of interbreeding between these populations.

引言：依托与单倍型（haplotype）及诱捕捕获模式相验证的生物物理模型方法，已有研究在半大陆尺度上模拟了草地贪夜蛾（fall armyworm）的迁飞轨迹，其起源地为得克萨斯州或佛罗里达州，迁飞范围覆盖落基山脉以东的美国大部分区域。然而，该验证分析中仍存在无法解释的变异，且已有研究报道草地贪夜蛾种群的模拟迁飞模式与多个点位（尤其是美国东北部及加拿大地区）的单倍型比例存在错配现象。
材料与方法：本研究利用纳入加拿大区域的扩充数据集，评估关联草地贪夜蛾种群越冬起源与北美地区推测扩散轨迹的单倍型模式的一致性，并将这些模式的地理分布与既往模型预测结果进行对比。
结果与讨论：本研究证实了既往模型构建工作的整体准确性，但在季末时段存在例外——本研究数据显示，此时入侵东北部并延伸至加拿大东部的种群中，得克萨斯州起源种群的占比更高。本研究明确了两类越冬种群分布范围的地理边界，并证实南卡罗来纳州以北区域常发生得克萨斯州与佛罗里达州起源迁飞种群的大规模混合。我们还探讨了这些迁飞轨迹的年际变异，并验证了阿巴拉契亚山脉（Appalachian Mountains）会影响单倍型地理分布模式这一假说。此外，本研究讨论了上述结果如何限制得克萨斯州与佛罗里达州起源种群间的基因交流，以及如何限制这两类种群杂交产生的遗传后果。