Plant Pest Diagnostics Branch

Sacramento, CA, United States

Plant Pest Diagnostics Branch

Sacramento, CA, United States

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Bilodeau G.J.,U.S. Department of Agriculture | Martin F.N.,U.S. Department of Agriculture | Coffey M.D.,University of California at Riverside | Blomquist C.L.,Plant Pest Diagnostics Branch
Phytopathology | Year: 2014

A molecular diagnostic assay for Phytophthora spp. that is specific, sensitive, has both genus- and species-specific detection capabilities multiplexed, and can be used to systematically develop markers for detection of a wide range of species would facilitate research and regulatory efforts. To address this need, a marker system was developed based on the high copy sequences of the mitochondrial DNA utilizing gene orders that were highly conserved in the genus Phytophthora but different in the related genus Pythium and plants to reduce the importance of highly controlled annealing temperatures for specificity. An amplification primer pair designed from conserved regions of the atp9 and nad9 genes produced an amplicon of ~340 bp specific for the Phytophthora spp. tested. The TaqMan probe for the genus-specific Phytophthora test was designed from a conserved portion of the atp9 gene whereas variable intergenic spacer sequences were used for designing the speciesspecific TaqMan probes. Specific probes were developed for 13 species and the P. citricola species complex. In silico analysis suggests that species-specific probes could be developed for at least 70 additional described and provisional species; the use of locked nucleic acids in TaqMan probes should expand this list. A second locus spanning three tRNAs (trnM-trnP-trnM) was also evaluated for genus-specific detection capabilities. At 206 bp, it was not as useful for systematic development of a broad range of species-specific probes as the larger 340-bp amplicon. All markers were validated against a test panel that included 87 Phytophthora spp., 14 provisional Phytophthora spp., 29 Pythium spp., 1 Phytopythium sp., and 39 plant species. Species-specific probes were validated further against a range of geographically diverse isolates to ensure uniformity of detection at an intraspecific level, as well as with other species having high levels of sequence similarity to ensure specificity. Both diagnostic assays were also validated against 130 environmental samples from a range of hosts. The only limitation observed was that primers for the 340 bp atp9-nad9 locus did not amplify Phytophthora bisheria or P. frigida. The identification of species present in a sample can be determined without the need for culturing by sequencing the genus-specific amplicon and comparing that with a reference sequence database of known Phytophthora spp.


Percy D.M.,University of British Columbia | Percy D.M.,Natural History Museum in London | Rung A.,Plant Pest Diagnostics Branch | Hoddle M.S.,University of California at Riverside
Zootaxa | Year: 2012

A revised checklist to the species of Psylloidea (Hemiptera) from California is presented, with information on host plant data, distributions, introduced and pest species, parasites, parasitoids, and predators, and biological control programs. The list includes 164 species, of which six are newly recorded. In total, this comprises a 26% increase in the number of species recorded for California since the last published checklist in 1988. Choricymoza Bliven is a new synonym of Phylloplecta Riley, and 10 species previously in Euphalerus Schwarz are recombined under Nyctiphalerus Bliven. California has the richest native psyllid fauna in North America, and the influence of climatic and floristic diversity on this diversification is considered. Copyright © 2012 · Magnolia Press.


Grimaldi D.A.,American Museum of Natural History | Arillo A.,Complutense University of Madrid | Cumming J.M.,Agriculture and Agri Food Canada | Hauser M.,Plant Pest Diagnostics Branch
ZooKeys | Year: 2011

Thirteen species of basal Brachycera (11 described as new) are reported, belonging to nine families and three infraorders. They are preserved in amber from the Early Cretaceous (Neocomian) of Lebanon, Albian of northern Spain, upper Albian to lower Cenomanian of northern Myanmar, and Late Cretaceous of New Jersey USA (Turonian) and Alberta, Canada (Campanian). Taxa are as follows, with significance as noted: In Stratiomyomorpha: Stratiomyidae (Cretaceogaster pygmaeus Teskey [2 new specimens in Canadian amber], Lysistrata emerita Grimaldi & Arillo, gen. et sp. n. [stem-group species of the family in Spanish amber]), and Xylomyidae (Cretoxyla azari Grimaldi & Cumming, gen. et sp. n. [in Lebanese amber], and an undescribed species from Spain). In Tabanomorpha: Tabanidae (Cratotabanus newjerseyensis Grimaldi, sp. n., in New Jersey amber). In Muscomorpha: Acroceridae (Schlingeromyia minuta Grimaldi & Hauser, gen. et sp. n. and Burmacyrtus rusmithi Grimaldi & Hauser gen. et sp. n., in Burmese amber, the only definitive species of the family from the Cretaceous); Mythicomyiidae (Microburmyia analvena Grimaldi & Cumming gen. et sp. n. and M. veanalvena Grimaldi & Cumming, sp. n., stem-group species of the family, both in Burmese amber); Apsilocephalidae or near (therevoid family-group) (Kumaromyia burmitica Grimaldi & Hauser, gen. et sp. n. [in Burmese amber]); Apystomyiidae (Hilarimorphites burmanica Grimald & Cumming, sp. n. [in Burmese amber], whose closest relatives are from the Late Jurassic of Kazachstan, the Late Cretaceous of New Jersey, and Recent of California). Lastly, two species belonging to families incertae sedis, both in Burmese amber: Tethepomyiidae (Tethepomyia zigrasi Grimaldi & Arillo sp. n., the aculeate oviscapt of which indicates this family was probably parasitoidal and related to Eremochaetidae); and unplaced to family is Myanmyia asteiformia Grimaldi, gen. et sp. n., a minute fly with highly reduced venation. These new taxa significantly expand the Mesozoic fossil record of rare and phylogenetically significant taxa of lower Brachycera. © David A. Grimaldi et al.


Wang Y.,China Agricultural University | Liu X.,China Agricultural University | Winterton S.L.,Plant Pest Diagnostics Branch | Yang D.,China Agricultural University
PLoS ONE | Year: 2012

Megaloptera are a basal holometabolous insect order with larvae exclusively predacious and aquatic. The evolutionary history of Megaloptera attracts great interest because of its antiquity and important systematic status in Holometabola. However, due to the difficulties identifying morphological apomorphies for the group, controversial hypotheses on the monophyly and higher phylogeny of Megaloptera have been proposed. Herein, we describe the complete mitochondrial (mt) genome of a fishfly species, Neochauliodes punctatolosus Liu & Yang, 2006, representing the first mt genome of the subfamily Chauliodinae. A phylogenomic analysis was carried out based on the mt genomic sequences of 13 mt protein-coding genes (PCGs) and two rRNA genes of nine Neuropterida species, comprising all three orders of Neuropterida and all families and subfamilies of Megaloptera. Both maximum likelihood and Bayesian inference analyses highly support the monophyly of Megaloptera, which was recovered as the sister of Neuroptera. Within Megaloptera, the sister relationship between Corydalinae and Chauliodinae was corroborated. The divergence time estimation suggests that stem lineage of Neuropterida and Coleoptera separated in the Early Permian. The interordinal divergence within Neuropterida might have occurred in the Late Permian. © 2012 Wang et al.


Gilligan T.M.,Colorado State University | Epstein M.E.,Plant Pest Diagnostics Branch | Hoffman K.M.,Primary State Entomologist
Proceedings of the Entomological Society of Washington | Year: 2011

The false codling moth, Thaumatotibia leucotreta (Meyrick), is one of the most destructive pests of avocado, citrus, and cotton in Africa. On July 24, 2008, a male of this species was identified from a pheromone trap located in Ventura County, California. Although larvae of T. leucotreta are frequently intercepted at U.S. ports-of-entry, primarily on bell peppers (Capsicum sp.), eggplant (Solanum melongena), and clmentines (Citrus sp.), this represents the first North American record outside of a port or international commercial shipment. Additional individuals have not been recorded from California suggesting that this species is not yet established in the state. We provide descriptions, illustrations, and other information to help in the identification of this species. Copyright © 2011 BioOne All rights reserved.


Kerr P.H.,Plant Pest Diagnostics Branch
ZooKeys | Year: 2011

Six new species are described, raising the number of North American Acomoptera species to seven and the genus total to ten, and nearly doubling the number of species within the putative clade containing Acomoptera, Drepanocercus, and Paratinia. Tese novel species forms have implications for the concept of Acomoptera that in turn, may impact our understanding of its generic relationships and the evolution and composition of Gnoristinae and Sciophilinae. Te new species, A. crispa, A. digitata, A. echinosa, A. forcu-lata, A. nelsoni, and A. vockerothi, are compared with the type species of the genus, A. plexipus (Garrett), whose diagnostic features are imaged and illustrated for the frst time. Te European species, A. difcilis (Dziedzicki) is also illustrated and compared. Acomoptera spinistyla (Søli) comb. n. is transferred from Drepanocercus. A key to species is provided. Future work will seek to incorporate this knowledge into a systematic phylogenetic study of relationships between these species and their sister taxa.


Kerr P.H.,Plant Pest Diagnostics Branch
Zootaxa | Year: 2010

Two new species of fungus gnats (Diptera: Mycetophilidae), Azana malinamoena and Azana frizzelli, spp. nov., are described and figured from California. These species represent the first records of Azana for western North America. A diagnosis of the genus Azana Walker is presented and a provisional key for the New World species of the genus is given. The discovery of A. malinamoena and A. frizzelli in California and their apparently close relationship to A. nigricoxa Strobl from south-western Europe (rather than to the only other Azana species known from North America, A. sinusa Coher) implies a more complicated biogeographic history of this genus in North America, one that probably includes multiple, independent dispersal events. Copyright © 2010 Magnolia Press.


This paper updates current knowledge of Rhagionidae and related taxa within the infraorder Tabanomorpha. An estimate of phylogeny for the group is presented, based on 127 morphological characters for 60 ingroup species and molecular characters consisting of 3200+ bp sequences of 28S rDNA for 38 ingroup species. The morphology and molecular datasets are analyzed separately and in a combined analysis, using parsimony, maximum likelihood, and Bayesian methods. Morphological and molecular data, when analyzed separately and in combination, yield similar hypotheses of the evolution within Tabanomorpha. Arthrocerinae (Rhagionidae), Chrysopilinae (Rhagionidae), Rhagioninae (Rhagionidae), Spaniinae (Rhagionidae), Tabanoidea (Pelecorhynchidae, Oreoleptidae, Athericidae, and Tabanidae), and Vermileonidae are recovered consistently. The relationships among the major tabanomorph clades, including Austroleptis Hardy and Bolbomyia Loew, remain weakly supported, however. Rhagionidae are recognized as a monophyletic group of four subfamilies and at least 15 extant genera. The subfamily Spaniinae is defined by a special modification of tergite 9 of the female genitalia, which is shared by members of Omphalophora Becker, Ptiolina Zetterstedt, Spania Meigen, Spaniopsis White, and Symphoromyia Frauenfeld. Litoleptis Chillcott is also placed in this group, however this could not be confirmed because females of this genus were not available. The concept of Omphalophora is clarified and the genus is resurrected from synonymy with Ptiolina. On this basis, several species are newly transferred to Omphalophora; they include O. cinereofasciata (Schummel 1837) n. comb., O. fasciata (Loew 1869b) n. comb., O. majuscula (Loew 1869b) n. comb., and O. nigripilosa (Hardy & McGuire 1947) n. comb. Chrysopilinae is defined by having scale-like setae on the thorax and femur, as in Chrysopilus Macquart, Schizella Bezzi, and Stylospania Frey. Solomomyia Nagatomi is recognized as a new junior synonym of Chrysopilus. Seven new names within the genus Chrysopilus are created for binomials that are preoccupied. These include C. amulus Kerr nom. nov. for C. latifrons Williston 1901 (preoccupied by C. latifrons Bezzi 1898), C. batak Kerr nom. nov. for C. tomentosus Meijere 1924 (preoccupied by C. tomentosus Bigot 1887), C. mawambus Kerr nom. nov. for C. obscuripes Brunetti 1927 (preoccupied by C. obscuripes Speiser 1923), C. meunieri Kerr nom. nov. for C. nagatomii Evenhuis 1994 (preoccupied by C. nagatomii Yang & Yang 1991), C. occidentalis Kerr nom. nov. for C. lucifer Adams 1904 (preoccupied by C. lucifer Walker 1852), and C. amorimi Kerr nom. nov. for C. fascipennis Bromley in Curran 1931 (preoccupied by C. fascipennis (Brunetti 1920)). Chrysopilus sinensis (Yang et al. 1997) n. comb. is transferred from Spatulina Szilády, where this species was originally placed. Arthrocerinae contains a single genus, Arthroceras Williston. Phylogenetic analyses consistently show strong support for a clade consisting of Arthrocerinae, Chrysopilinae, and Spaniinae; most females of these subfamilies have spermathecal duct accessory glands. Spermathecal duct accessory glands are reported here for the first time and are unique in Tabanomorpha. Rhagioninae is the earliest branching subfamily of Rhagionidae. The saw sclerite in the larval mandible may be synapomorphic for this subfamily. Members of Rhagioninae include Atherimorpha White, Desmomyia Brunetti, Rhagio Fabricius, and Sierramyia Kerr gen. nov. Atherimorpha setosus (Philippi 1865) is recognized as a new synonym of Atherimorpha praefica (Philippi 1865) and Neorhagio Lindner 1924 is recognized as a new synonym of Atherimorpha. Sierramyia gen. nov. is erected for two species from Mexico that were originally placed in Neorhagio (type species: Neorhagio caligatus Santos 2006). Rhagina Malloch is recognized as a new synonym of Rhagio. As a result, Rhagio yangi Kerr nom. nov. is created for R. sinensis Yang & Yang 1993a (preoccupied by R. sinensis Yang & Nagatomi 1992, n. comb.). Two enigmatic genera, Bobomyia Loew and Austroleptis Hardy are retained within their own families, Bolbomyiidae status revised and Austroleptidae, respectively. Alloleptis tersus Nagatomi & Saigusa is incertae sedis within Rhagionoidea. Comments on larval morphology of Tabanomorpha are given in light of this work. A key is given to all families of Tabanomorpha and genera of Rhagionidae. The genera of Austroleptidae, Bolbomyiidae, and Rhagionidae are diagnosed, re-described, and re-classified based on characters and relationships established by the phylogenetic analyses, with a list of included species for each genus. A history of the recent classification of Rhagionidae and related taxa is also provided. © 2010 Magnolia Press.


A new psyllid pest of ficus, Macrohomotoma gladiata (Hemiptera: Sternorrhyncha: Psylloidea), is reported for the first time from North America (California, U.S.A.). Notes on another adventive psyllid species that has been collected from ficus in California, Homotoma ficus, are given, together with a list diagnostic features that separate between M. gladiata and H. ficus. © 2016 Check List and Authors.


BACKGROUND: Drosophila suzukii is an oriental species first reported outside Asia from Hawaii in 1980. The first confirmed records for the continental United States were made in 2008 in California. The identification of this pest is difficult because very few published resources exist. RESULTS: It has since been recorded in Oregon, Washington, British Columbia, Alberta, Manitoba, Ontario, Quebec, Utah, Michigan, Wisconsin, Louisiana, North Carolina, South Carolina and Florida. Males are relatively easy to identify by the black apical wing spots and the single row of combs on the first and second tarsal segment of the fore leg. The male genitalia are also very characteristic and will aid in identifying teneral specimens. Females can be identified by the large ovipositor, which is 6-7 times as long as the diameter of the spermatheca. Immature stages can only be identified by molecular techniques. CONCLUSION: Although this species has been recorded from many US states and Canadian provinces, it has not been established in all of these places, and the main economic damage is restricted to the western part of North America. With the characters laid out in this paper, it should be possible to identify the pest with high certainty. © 2011 Society of Chemical Industry.

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