Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 17, 2000
Publication Date: N/A
Interpretive Summary: The pea leafmining fly Liriomyza huidobrensis (Diptera: Agromyzidae) is a pest of many vegetable and flower crops including peas, beans, melons, tomatoes, potatos, celery, garlic, lettuce, chrysanthemums, and carnations. During outbreaks this insect can cause severe damage to these crops, resulting in substantial economic losses. Originally known from the western United States and South America, this fly has recently been introduced into many locations around the world. This research investigated the evolutionary relationships of pea leafmining flies from around the world using DNA sequence data. Results indicate that the pea leafminer is comprised of two cryptic species, one located in North America and one in South America. This may explain some of the differences that have been observed in pest status and levels of insecticide resistance between populations from different locations. This work also has implication for quarantine regulations. This research is of interest to researchers, pest management specialists, and quarantine officials working with the pea leafminer.
Technical Abstract: Phylogenetic relationships among populations of the polyphagous leafminer Liriomyza huidobrensis (Diptera: Agromyzidae) were investigated using DNA sequence data. Maximum parsimony analysis of 941 bp of mitochondrial cytochrome oxidase genes showed that L. huidobrensis contains two well-defined monophyletic groups, one comprised of specimens from California and Hawaii and one comprised of specimens from South and Centra America together with populations that have been recently introduced into other parts of the world. The differentiation between the two clades within L. huidobrensis is equivalent to that seen between other agromyzid species, suggesting that L. huidobrensis as currently defined contains two cryptic species. This finding is consistent with field observations of differences in pest status and insecticide resistance between L. huidobrensis populations. Until additional studies are complete, no changes in L. huidobrensis taxonomy are proposed. However, researchers and quarantine officials may wish to consider the findings of the present study in designing research, pest management, and quarantine programs for L. huidobrensis.