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Tuckerella japonica Ehara (Acari: Tetranychoidea: Tuckerellidae) was found on stems of seedling plants of Camellia sinensis (L.) O. Kuntze (Theaceae) in the continental USA. This mite is able to pierce exposed green periderm tissue with its paired stylets on 1- to 3- or 4-year-old stems where the outer bark had split longitudinally. The mite was not found on branches older than 3 or 4 years, where splitting diminished and, eventually, a uniform covering of bark was formed. The mouthparts of T. japonica were examined under scanning electron microscopy and their external morphology was compared with known Tetranychoidea. There were usually one or two feeding holes in an area where the female subsequently deposited one or more eggs. Females were observed defending the areas where their eggs and/or young occurred. This behavior along with potentially limited access to exposed periderm or availability of shoots in the rows of plants may restrict higher populations of T. japonica from becoming established. The potential of T. japonica as an economic pest remains unknown at this time. [ABSTRACT FROM AUTHOR]

Examines the determination of the distribution of constitutive heterochromatic DNA in the United States. Characterization of the polymorphism; Development of a reference karyotype of tetraploid alfalfa; Use of C-banding and image analysis.

An adventive aphid and novel host–parasitoid association from cultivated strawberry (Fragaria × ananessa Duch. cv. Chandler; Fragaria × ananessa Duch. cv. Camarosa) in Mississippi, USA are reported herein. The aphid, first detected in high tunnel cultivation, was found predominately on newly emerged, not fully developed leaflets of daughter plants in the Fall of 2016. By 2017, aphids and their associated mummies were observed on fully developed leaflets on mother plants of both cultivars. The aphid was identified as Aphis ruborum (Börner & Schilder) using morphology and DNA barcoding studies. In addition, DNA barcoding identified parasitoid adults emerging from aphid mummies as two cryptic species, Aphelinus varipes (Foerster) and Aphelinus albipodus Hayat and Fatima. Occurrence of A. ruborum in Mississippi represents a new state record and the eastern-most established record in the United States. The A. ruborum – A. varipes or A. albipodus host–parasitoid association is reported for the first time anywhere in the world. [ABSTRACT FROM AUTHOR]

The invasive redbay ambrosia beetle, Xyleborus glabratus, is the primary vector of Raffaelea lauricola, a symbiotic fungus and the etiologic agent of laurel wilt. This lethal disease has caused severe mortality of redbay (Persea borbonia) and swampbay (P. palustris) trees in the southeastern USA, threatens avocado (P. americana) production in Florida, and has potential to impact additional New World species. To date, all North American hosts of X. glabratus and suscepts of laurel wilt are members of the family Lauraceae. This comparative study combined field tests and laboratory bioassays to evaluate attraction and boring preferences of female X. glabratus using freshly-cut bolts from nine species of Lauraceae: avocado (one cultivar of each botanical race), redbay, swampbay, silkbay (Persea humilis), California bay laurel (Umbellularia californica), sassafras (Sassafras albidum), northern spicebush (Lindera benzoin), camphor tree (Cinnamomum camphora), and lancewood (Nectandra coriacea). In addition, volatile collections and gas chromatography-mass spectroscopy (GC-MS) were conducted to quantify terpenoid emissions from test bolts, and electroantennography (EAG) was performed to measure olfactory responses of X. glabratus to terpenoids identified by GC-MS. Significant differences were observed among treatments in both field and laboratory tests. Silkbay and camphor tree attracted the highest numbers of the beetle in the field, and lancewood and spicebush the lowest, whereas boring activity was greatest on silkbay, bay laurel, swampbay, and redbay, and lowest on lancewood, spicebush, and camphor tree. The Guatemalan cultivar of avocado was more attractive than those of the other races, but boring response among the three was equivalent. The results suggest that camphor tree may contain a chemical deterrent to boring, and that different cues are associated with host location and host acceptance. Emissions of α-cubebene, α-copaene, α-humulene, and calamenene were positively correlated with attraction, and EAG analyses confirmed chemoreception of terpenoids by antennal receptors of X. glabratus.