Abstract
Simple SummaryPolyphagous leaf-mining flies of the genus Liriomyza are pests that pose a serious threat to agricultural and horticultural industries. The endosymbiotic bacterium Wolbachia has been proposed as a useful biocontrol strategy for managing pests, but few studies have so far examined Wolbachia in leafminers. We find a high incidence of related Wolbachia in a survey of infections in 13 dipteran leafminer species collected from Australia and elsewhere which could potentially be useful for the incompatible insect technique (IIT) of pest suppression. We performed curing and crossing experiments on L. brassicae to demonstrate the presence of cytoplasmic incompatibility (CI) needed for IIT, providing a foundation for future transfection of CI Wolbachia from L. brassicae to other Liriomyza pests. Overall, these findings highlight a high incidence of Wolbachia in leaf-mining Diptera, potential horizontal transmission events and possible applications of Wolbachia-based biocontrol strategies for Liriomyza pests.The maternally inherited endosymbiont, Wolbachia pipientis, plays an important role in the ecology and evolution of many of its hosts by affecting host reproduction and fitness. Here, we investigated 13 dipteran leaf-mining species to characterize Wolbachia infections and the potential for this endosymbiont in biocontrol. Wolbachia infections were present in 12 species, including 10 species where the Wolbachia infection was at or near fixation. A comparison of Wolbachia relatedness based on the wsp/MLST gene set showed that unrelated leaf-mining species often shared similar Wolbachia, suggesting common horizontal transfer. We established a colony of Liriomyza brassicae and found adult Wolbachia density was stable; although Wolbachia density differed between the sexes, with females having a 20-fold higher density than males. Wolbachia density increased during L. brassicae development, with higher densities in pupae than larvae. We removed Wolbachia using tetracycline and performed reciprocal crosses between Wolbachia-infected and uninfected individuals. Cured females crossed with infected males failed to produce offspring, indicating that Wolbachia induced complete cytoplasmic incompatibility in L. brassicae. The results highlight the potential of Wolbachia to suppress Liriomyza pests based on approaches such as the incompatible insect technique, where infected males are released into populations lacking Wolbachia or with a different incompatible infection.
Highlights
The genus Liriomyza is one of the most widely studied and well-documented groups in the Agromyzidae
We found that all individuals of L. huidobrensis, L. chinensis, L. bryoniae, L. brassicae, L. chenopodii, P. plantaginis, P. syngenesiae, P. praecellens, S. australis and S. flava tested were positive for Wolbachia, while all C. milleri individuals tested negative
Wolbachia superinfections were detected in P. syngenesiae in one population (Flemington Bridge–Australia) based on sequencing data; we found 192 individuals were infected with wLsatA as determined from screens with primers specific to this infection, but three of these individuals were diagnosed as having two different wsp alleles based on universal primers
Summary
The genus Liriomyza is one of the most widely studied and well-documented groups in the Agromyzidae. Introduced leaf-mining pests are prone to outbreaks and rapidly become uncontrollable, which has allowed the establishment of these species in most countries [3,4,5,6,7]. This includes Australia, where L. sativae and L. huidobrensis have become established pests and L. trifolii has recently invaded, posing a significant economic threat to Australian agricultural and horticultural industries [8,9,10]. Adults and larvae of Liriomyza flies cause damage to host plants. Female flies damage plants by puncturing the epidermis of host plant leaves with their ovipositor for feeding and egg-laying [11,12]. Most damage is caused by the larval stage tunneling through the palisade and spongy mesophyll cells, producing serpentine mines and reducing the photosynthetic capacity of plants [16], with severely infested leaves falling off plants
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
