With taxonomic revisions at genus level and above, species including agricultural pests, that have been classed as "Psyllids" may now placed in other families including the
Carsidaridae,
Liviidae and
Triozidae.
Citrus greening, also known as
huanglongbing, associated with the presence of a bacterium
Liberibacter asiaticum, is an example of a plant pathogen that has coevolved with its insect vector, the "
Asian citrus psyllid", ACP,
Diaphorina citri, such that the pathogen causes little or no harm to the insect, but causes a major disease which can reduce citrus quality, flavor, and production, as well as causing citrus trees to die. ACP was found in Florida in 1998, and has since spread across the southern US into Texas. This disease was found in Florida citrus groves in 2005. Management methods to reduce the spread of this disease and psyllid populations depend on an integrated pest management approach using insecticides, parasitoids, predators, and pathogens specific to ACP. Due to the spread of citrus greening worldwide and the growing importance of psyllid-spread diseases, an International Psyllid Genome Consortium was established. Insect genomics provides important information on the genetic basis of the pest's biology which may be altered to suppress psyllid populations in an environmentally friendly manner. The emerging psyllid genome continues to elucidate psyllid biology, expanding what is known about gene families, genetic variation, and gene expression in insects. Thus far, two new psyllid viruses have been discovered, and are being examined as potential biological control agents to reduce psyllid populations. Psyllid cell cultures have also been established by several researchers working with virus propagation, and as a system to propagate
C. liberibacter for molecular studies on infection and replication. Studies on the microbiota have also identified four new species of bacteria. Thus far, 10 microbial organisms have been identified within these psyllids, among them the primary endosymbiont, whose genome has been sequenced and posted at the NCBI database, as well as a
Wolbachia species. ==References==