Microsatellite‐based analysis of genetic structure and gene flow of Mythimna separata (Walker) (Lepidoptera: Noctuidae) in China

• Published in: Ecology and evolution Vol. 9; no. 23; pp. 13426 - 13437
• Main Authors: Li, Mei‐Mei, Li, Bo‐Liao, Jiang, Shi‐Xiong, Zhao, Yu‐Wan, Xu, Xiang‐Li, Wu, Jun‐Xiang
• Format: Journal Article
• Language: English
• Published: England John Wiley & Sons, Inc 01.12.2019; John Wiley and Sons Inc; Wiley
• Subjects: Bayesian analysis; Biological evolution; Cluster analysis; Clustering; Deoxyribonucleic acid; Differentiation; Discriminant analysis; DNA; Evolution; Gene flow; Genetic analysis; Genetic distance; Genetic diversity; Genetic markers; Genetic structure; Insect migration; Microsatellites; Mythimna separata; Natural populations; Original Research; Outbreaks; Pest outbreaks; Population; Population genetics; population structure; Populations; Provinces; China; gene flow; microsatellites; genetic diversity; population structure; Mythimna separata
• ISSN: 2045-7758; 2045-7758
• DOI: 10.1002/ece3.5799

The oriental armyworm, Mythimna separata, is a serious agricultural pest in China. Seasonal and roundtrip migration has recently led to sudden, localized outbreaks and crop losses. To evaluate genetic differentiation between populations in eastern and western China and elucidate gene flow, the genetic structure of 20 natural populations from nine provinces was examined using seven microsatellite markers. The results indicated high genetic diversity. However, little to moderate (0 < FST < 0.15) genetic differentiation was detected, and there was no correlation between genetic distance and geographical distance. Bayesian clustering analysis identified three groups whereas discriminant analysis of principal components identified ten clusters that were considered as two clear‐cut clusters and one admixed group. Gene flow occurred frequently in most population pairs, and an asymmetrical migration rate was detected in several pairwise population comparisons. The bottleneck test showed that few populations had experienced recent bottlenecks. Correspondingly, large‐scale and long‐distance migration of M. separata has caused low genetic differentiation and frequent gene exchange. Our findings are important for studying genetic evolution and help to improve predictions of M. separata outbreaks in China. Our study evaluated the population structure, genetic differentiation, and gene flow between geographically distant oriental armyworm populations in eastern and western China using seven microsatellite markers. The results showed that there was little genetic differentiation but high genetic variability and extensive gene flow among populations. We believe that our study makes a significant contribution to the literature because Mythimna separata is a serious agricultural pest, and our results will help to improve predictions of its outbreaks in China.