Insight into the Migration Routes of Plutella xylostella in China Using mtCOI and ISSR Markers.

Jiaqiang Yang,Shaoli Wang,Youjun Zhang,Qingjun Wu,Xiangjing Wang,Wen Xie,Baoyun Xu,Lixia Tian,Chao-Dong Zhu

doi:10.1371/journal.pone.0130905

Abstract

The larvae of the diamondback moth, Plutella xylostella, cause major economic losses to cruciferous crops, including cabbage, which is an important vegetable crop in China. In this study, we used the mitochondrial COI gene and 11 ISSR markers to characterize the genetic structure and seasonal migration routes of 23 P. xylostella populations in China. Both the mitochondrial and nuclear markers revealed high haplotype diversity and gene flow among the populations, although some degree of genetic isolation was evident between the populations of Hainan Island and other sampling sites. The dominant haplotypes, LX1 and LX2, differed significantly from all other haplotypes both in terms of the number of individuals with those haplotypes and their distributions. Haplotypes that were shared among populations revealed that P. xylostella migrates from the lower reaches of the Yangtze River to northern China and then to northeastern China. Our results also revealed another potential migration route for P. xylostella, i.e., from southwestern China to both northwestern and southern China.

Highlights

The diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), which originated in the Mediterranean region or South Africa [1,2], is considered a globally distributed insect pest [3]
Neutrality tests showed that the Tajima’s D and Fu’s FS values of all P. xylostella populations were negative (Table 2), which does not support a neutral model of evolution and suggests that population expansion, genetic hitchhiking, and/or selection have occurred during the evolutionary history of P. xylostella
By analyzing mtCOI and Inter-simple sequence repeat (ISSR) data, we have determined that P. xylostella populations in China exhibit high genetic variability at the nucleotide level and high mitochondrial haplotype doi:10.1371/journal.pone.0130905.g004

Summary

Introduction

The diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae), which originated in the Mediterranean region or South Africa [1,2], is considered a globally distributed insect pest [3]. P. xylostella can cause crop losses of more than 90% [4]. The total annual cost of damage caused by P. xylostella was recently estimated to be US$4–5 billions [5]. In China, P. xylostella has been a major pest of cruciferous crops since the 1970s and is found in most cruciferous crop-growing areas. P. xylostella is considered a long-distance migratory species [3]. P. xylostella cannot survive in the cold winter conditions of regions such as western Canada, northern Japan, or northern China. Re-colonization from warmer regions where populations persist year round occurs annually [6,7,8,9]

Methods

Results

Conclusion