Genetic differentiation among various populations of the diamondback moth, Plutella xylostella Lepidoptera Yponomeutidae

Abstract

Genetic variation among 14 populations of Plutella xylostella (Linnaeus) from USA (Geneva, New York), Brazil (Brasilia), Japan (Okayama), The Philippines (Caragan de Oyo), Uzbekistan (Tashkent), France (Montpellier), Benin (Cotonou), South Africa (Johannesburg), Réunion Island (Montvert), and five localities in Australia (Adelaide, Brisbane, Mareeba, Melbourne, Sydney) were assessed by analysis of allozyme frequencies at seven polymorphic loci. Most of the populations were not in Hardy-Weinberg equilibrium and had a deficit in heterozygotes. The global differentiation among populations was estimated by the fixation index (Fst) at 0.103 for the 14 populations and at 0.047 when populations from Australia and Japan, which differed most and had a strong genetic structure, were excluded from the analysis. By contrast, the populations from Benin (West Africa) and Brazil (South America) were very similar to each other. Genetic differentiation among the populations was not correlated with geographical distance.

Genetic Diversity in Apple Fruit Moth Indicate Different Clusters in the Two Most Important Apple Growing Regions of Norway

“…AFLP data analysis of individual male and female did not reveal any marker specific for sex determination, and clustering analyses of males and females did not show any particular pattern. This result is similar to the one obtained in the Lepidoptera species "Plutella xylostella" [51]. For the same species, in Cameroon and China substantial genetic variation and high gene flow among regions have been reported [52,53].…”

Plutella australiana (Lepidoptera, Plutellidae), an overlooked diamondback moth revealed by DNA barcodes

“…The past oversight of the presence of two Plutella species in Australia likely explains the regional allozyme variation previously detected in Australian populations of Plutella xylostella (Pichon et al 2006). For example, the congruence between populations near Sydney and those in other nations could be explained if Plutella xylostella dominated collections from this locality, while those at the other sites were dominated by Plutella australiana .…”

“…These genetic results suggest substantial gene flow among widely separated populations, supporting expectations from observational studies which have indicated that Plutella xylostella is highly migratory with populations in cool temperate regions annually reestablished from southerly locales (Harcourt 1986, Chapman et al 2002). However, another allozyme study on Plutella xylostella from five continents (Africa, Asia, Australia, Europe, North America) provided a slightly different perspective (Pichon et al 2006). Populations from most sites had similar allele frequencies, but the population from Japan showed considerable differentiation from those at the other sites, while the Australian populations showed variability.…”

“…Specimens collected near Sydney possessed allele frequencies similar to populations in other nations (except Japan), but those from four other sites were distinctive. Based on these results, Pichon et al (2006) concluded that gene flow was sometimes insufficient to prevent regional genetic divergence.…”

Genetic diversity in European pollen beetle, Meligethes aeneus (Coleoptera: Nitidulidae), populations assessed using AFLP analysis

“…In two studies of another important Brassica pest, the moth Plutella xylostella, there was no relationship between genetic and geographical distances at large geographical scales (Endersby et al, 2006;Pichon et al, 2006). One interpretation was that insects can be spread with plant material or that a recent rapid expansion of Brassica cultivation with small numbers founding local populations.…”