Geographically Based Diversity in Mitochondrial DNA of North American Lygus lineolaris (Hemiptera: Miridae)

Abstract

The tarnished plant bug, Lygus lineolaris (Palisot de Beauvois), is a highly polyphagous insect pest. It is the most widely distributed Lygus species in North America, and it is the most prevalent member of the genus Lygus in the eastern half of the continent. We sampled multiple populations of L. lineolaris from three disparate regions of North America, and used parts of the mitochondrial genes cytochrome oxidase 1 and cytochrome oxidase 2 as markers to assess intraspecific diversity of this species. Results indicated that there is an association between genetic population structure and geography. Neighbor-joining, maximum parsimony, Bayesian inference analysis, and maximum likelihood trees suggested that most L. lineolaris individuals belong to two closely related clades showing sympatric distribution. Mitochondrial DNA haplotypes common to widely dispersed populations were observed. Morphological identities of five L. lineolaris samples that formed an outlier clade indicated incongruence between morphological identity and genetic data. Individuals from the two major clades and one disparate clade did not exhibit recognizable morphological differences. No strong host plant associations were observed among clades, thus, genetic structuring in this species appears to mostly be geographically based. This study represents the first attempt to survey cytochrome oxidase 1 and cytochrome oxidase 2 variation within L. lineolaris and to use those genes to construct a molecular phylogeny for this species.

Habitat or temporal isolation: Unraveling herbivore–parasitoid speciation patterns using double digest RADseq

“…These results show that Lygus species are truly generalists as we found no genetic divergence based on host. This lack of HAD is consistent with studies of other Lygus species such as L. lineolaris (Burange et al., ) and L. hesperus (Zhou et al., ) despite the detection of population‐level differences, indicating that factors other than HAD likely drove their evolution.…”

“…The herbivores in this system are plant bugs in the genus Lygus Hahn (Hemiptera: Miridae), which include many species of generalist agricultural pests (such as Lygus lineolaris Palisot de Beauvois) that feed on a variety of economically important crops. Although HAD has been recorded from other Miridae (Hereward, Walter, Debarro, Lowe, & Riginos, 2013), no evidence of HAD has been shown in Lygus species despite the detection of population-level differences based on geography (Burange, Roehrdanz, & Boetel, 2012;Zhou, Kandemir, Walsh, Zalom, & Lavine, 2012). Lygus have one to three generations per year depending on the temperature, where southern populations in warmer climates are multivoltine and northern populations in cooler climates tend to be univoltine (Cárcamo et al, 2002;Haye et al, 2013).…”

Building-Up of a DNA Barcode Library for True Bugs (Insecta: Hemiptera: Heteroptera) of Germany Reveals Taxonomic Uncertainties and Surprises

“…Distinct lineages of mitochondrial DNA can be caused by various effects. These include population separation by phylogeographic events [116] – [119] , incomplete lineage sorting [120] – [123] , the presence of maternally inherited endosymbionts (e.g. Wolbachia [124] , [125] ), and simply the existence of cryptic species [26] , [126] , [127] .…”