Worldwide population genetic structure of the oriental fruit moth (Grapholita molesta), a globally invasive pest

Abstract

BackgroundInvasive pest species have large impacts on agricultural crop yields, and understanding their population dynamics is important for ensuring food security. The oriental fruit moth Grapholita molesta is a cosmopolitan pest of stone and pome fruit species including peach and apple, and historical records indicate that it has invaded North and South America, Europe, Australia and Africa from its putative native range in Asia over the past century.ResultsWe used 13 microsatellite loci, including nine newly developed markers, to characterize global population structure of G. molesta. Approximately 15 individuals from each of 26 globally distributed populations were genotyped. A weak but significant global pattern of isolation-by-distance was found, and G. molesta populations were geographically structured on a continental scale. Evidence does not support that G. molesta was introduced to North America from Japan as previously proposed. However, G. molesta was probably introduced from North America to The Azores, South Africa, and Brazil, and from East Asia to Australia. Shared ancestry was inferred between populations from Western Europe and from Brazil, although it remains unresolved whether an introduction occurred from Europe to Brazil, or vice versa. Both genetic diversity and levels of inbreeding were surprisingly high across the range of G. molesta and were not higher or lower overall in introduced areas compared to native areas. There is little evidence for multiple introductions to each continent (except in the case of South America), or for admixture between populations from different origins.ConclusionsCross-continental introductions of G. molesta appear to be infrequent, which is surprising given its rapid worldwide expansion over the past century. We suggest that area-wide spread via transport of fruits and other plant materials is a major mechanism of ongoing invasion, and management efforts should therefore target local and regional farming communities and distribution networks.

Response of heat shock protein genes of the oriental fruit moth under diapause and thermal stress reveals multiple patterns dependent on the nature of stress exposure

“…The strong sequence conservation of large Hsps was not matched by functional conservation of expression patterns. These results as well as the different impact of acute and ramping stress on Hsps provides the basis for future functional studies in this important invasive pest which has developed a worldwide distribution from the early twentieth century and continues to cause significant economic damage on a global scale (Kirk et al 2013). Hsps may have played a role in the rapid establishment and/or spread of OFM in temperate and tropical areas to help counter both heat waves in summer and cold environments in winter.…”

“…The oriental fruit moth (OFM), Grapholita molesta, one of the world's most invasive orchard pest insect of stone and pome fruits, causes severe economic loss in the global fruit industry (Jones et al 2010;Kirk et al 2013;Russell 1986). OFM has gained recognition as a pest of peaches and other fruit crops since its introduction into the Americans in the last century (Jones 2010).…”

High Genetic Diversity and Structured Populations of the Oriental Fruit Moth in Its Range of Origin

“…The oriental fruit moth is not only a key pest of rosaceae fruit trees in its native range in Asia, requiring major pest management input [11], [12], [57], but has invaded all other fruit growing continents, posing major challenges to sustainable fruit tree protection [10], [51], [58]. The current study is the first to show that population genetic structure of this pest may be changing with the host switch from the primary host peach to the secondary hosts pear and apple in the late part of the season, and this finding might provide useful information for the design of future season-long pest management programs.…”

“…Its putative native range includes China, where it is thought to have co-evolved with its primary host peach [9], [10], but little is known yet about its population genetics in this area. This moth completes three to seven generations per year depending on latitude and elevation [11], [12].…”

Phenological responses and a comparative phylogenetic insight of Anarsia lineatella and Grapholita molesta between distinct geographical regions within the Mediterranean basin

“…The peach twig borer that is common in South Europe and the Mediterranean basin is found worldwide wherever stone fruits are grown, while the oriental fruit moth which originated from East Asia is currently one of the economically most destructive pest species of stone and pome fruits (Kirk et al. ). In most cases, both species are active and appear simultaneously during growth season while also sharing similarities in their infestation (Balachowsky ; Damos and Savopoulou‐Soultani , ).…”