Population structure of a global agricultural invasive pest, Bactrocera dorsalis (Diptera: Tephritidae)

Abstract

Bactrocera dorsalis, the Oriental fruit fly, is one of the world's most destructive agricultural insect pests and a major impediment to international fresh commodity trade. The genetic structuring of the species across its entire geographic range has never been undertaken, because under a former taxonomy B. dorsalis was divided into four distinct taxonomic entities, each with their own, largely non‐overlapping, distributions. Based on the extensive sampling of six a priori groups from 63 locations, genetic and geometric morphometric datasets were generated to detect macrogeographic population structure, and to determine prior and current invasion pathways of this species. Weak population structure and high genetic diversity were detected among Asian populations. Invasive populations in Africa and Hawaii are inferred to be the result of separate, single invasions from South Asia, while South Asia is also the likely source of other Asian populations. The current northward invasion of B. dorsalis into Central China is the result of multiple, repeated dispersal events, most likely related to fruit trade. Results are discussed in the context of global quarantine, trade, and management of this pest. The recent expansion of the fly into temperate China, with very few associated genetic changes, clearly demonstrates the threat posed by this pest to ecologically similar areas in Europe and North America.

Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is not invasive through Asia: It's been there all along

“…The centre of origin of B. dorsalis has been argued by several workers to be southern China or South‐East Asia (Aketarawong et al, , ; Schutze et al, ; Shi et al, ; Wan et al, ), but these papers all focused their population sampling within South‐East Asia and China and several analysed and/or interpreted their results explicitly within a conceptual framework that Taiwan or mainland China was the original source of the fly. In contrast, Qin et al () with a global B. dorsalis population coverage identified South Asia (India + Bangladesh) as the likely centre of origin for the species. Under this scenario, B. dorsalis evolved on the Indian subcontinent and migrated from there into South‐East Asia during pre‐history: this alternative hypothesis that should be further tested given a more accurate understanding of the historical distribution records of the fly.…”

“…Through a combination of humanassisted carriage and adult fly movement, B. dorsalis is also highly invasive. Within the last 20 years, the fly has entered and spread throughout sub-Saharan Africa (Ekesi, Meyer, Mohamed, Virgilio, & Borgemeister, 2016;Ekesi, Mohamed, & DeMeyer, 2016), is routinely detected and kept under regulatory control in California and Florida (McInnis et al, 2017;Papadopoulos, Plant, & Carey, 2013;Vargas et al, 2014), has begun an northward migration into temperate China (Qin et al, 2018) and most recently has been detected in the field in Europe (Nugnes, Russo, Viggiani, & Bernardo, 2018). Zeng et al (2019) have recently published a review of the global distribution and invasion history of B. dorsalis.…”

Mutation of Bdpaired induces embryo lethality in the oriental fruit fly, Bactrocera dorsalis

“…The oriental fruit fly, Bactrocera dorsalis , is one of the most destructive invasive pests, attacking a wide range of commercial fruits and vegetables in most parts of the world . Its rapid invasive capacity represents a serious threat to the global economy and food security . Currently, the oriental fruit fly is mainly managed using pesticides, which raises concerns regarding the development of pest resistance, environmental pollution, and human health .…”

“…1,2 Its rapid invasive capacity represents a serious threat to the global economy and food security. [3][4][5] Currently, the oriental fruit fly is mainly managed using pesticides, which raises concerns regarding the development of pest resistance, 6 environmental pollution, and human health. 7 Although the male annihilation technique (MAT) and sterile insect technique (SIT) have been used to control this fruit fly, there is a loss of mating competitiveness in the irradiated males compared with that of the wild-types.…”

Temperature effects on “overwintering” phenology of a polyphagous, tropical fruit fly (Tephritidae) at the subtropical/temperate interface

“…While most tropical fruit flies remain restricted to the tropics, there are some notable exceptions. The highly destructive oriental fruit fly, B. dorsalis (Hendel), is currently extending its range northwards into temperate central China (Han et al, 2011;Qin et al, 2018), now occurring in provinces which have previously been considered climatically unsuitable for the fly (Stephens, Kriticos, & Leriche, 2007). Similarly, Mediterranean fruit fly, Ceratitis capitata (Weidemann), is currently expanding its range into temperate central Europe (Papadopoulos, 2014), again well north of where models predict climate will become limiting (Vera, Rodriguez, Segura, Cladera, & Sutherst, 2002).…”