|De Barro, Paul|
|Shatters, Robert - Bob|
Submitted to: Bulletin of Entomological Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/29/2012
Publication Date: 3/1/2012
Citation: Boykin, L.M., De Barro, P., Hall, D.G., Hunter, W.B., McKenzie, C.L., Powell, C.A., Shatters, Jr., R.G. 2012. Overview of worldwide diversity of Diaphorina citri Kuwayama mitochondrial cytochrome oxidase 1 haplotypes: Two Old World lineages and a New World invasion. Bulletin of Entomological Research 17:1-10. Available: DOI: http://dx.doi.org/10.1017/S0007485312000181. Interpretive Summary: The asian citrus psyllid (Diaphorina citri) is an invasive pest of citrus native to southern asia that has spread worldwide. This insect vectors a devastating citrus disease known as citrus greening or Huanglongbing (HLB). Citrus greening has also spread worldwide presumably carried by the asian citrus psyllid. Because the spread of citrus greening in the field is thought to occur only by psyllid vectoring, methods of controlling or eliminating the psyllid will as a result directly reduce or eliminate the spread of citrus greening. Understanding the genetic nature of the insects for which control strategies are being developed can greatly improve the development of effective IPM strategies. For example, genetic diversity in susceptibility or resistance to pesticides, predatory insects, or diseases among different populations or strains is a known phenomenon in insects. Therefore understanding the genetic relationship of psyllid populations recently introduced into the United States to all known populations in the world provides valuable data in developing IMP strategies. We have modified a method of genetic analysis that allowed us to classify the relationship of psyllids in the U. S. to worldwide populations. The work showed that the U.S. population represents only one of two distinct populations worldwide. This information is now being used to develop IPM strategies that specifically target the genetic group that is present within the U.S.
Technical Abstract: We utilized a Bayesian phylogenetic technique to resolve global relationships of Diaphorina citri populations. This is the first global phylogenetic study of D. citri. New mitochondrial primers were designed from an EST library and an 821 base pair region of the COI was amplified and sequenced. The dataset consisted of 281 individual D. citri from around the world. Diaphorina is a monophyletic species and there are two well-supported clades within the phylogeny. All of the samples from the United States (Florida and Texas) are represented in only one major defined clade in which all Sauia Arabia samples were also limited. Within this major clade, a small but well supported subclade also existed that contained samples only from Puerto Rico and Guadelope. This suggests that introductions of psyllids into the U.S. occurred via a route different than that which lead to the psyllids in Puerto Rico and Guadelope. Sequences from all other locations fell into an unresolved set representing many worldwide regions containing this psyllid. This large set of unresolved individuals indicates the need for more sensitive methods of phylogenetic inference, perhaps using microsatellite data.