Numbers and types of arthropods overwintering on common mullein, Verbascum thapsus L. (Scrophulariaceae), in a central Washington fruit-growing region

Densities and types of arthropods overwintering on common mullein, Verbascum thapsus L., in a fruit-growing region of Central Washington were determined. Over 45,000 arthropods were collected from 55 plants (5 plants from each of 11 sites), dominated numerically by Acari and Thysanoptera. Insects representing 8 orders and 29 families were identified, distributed both in the basal leaf rosettes and in the stalk material of the plants. One specialist insect herbivore of mullein, the mullein thrips, Haplothrips verbasci (Osborn), was abundant at all sites. Several pest and predatory taxa that commonly occur in orchards were also collected, suggesting that mullein may be a source of overwintered pests or predators moving into orchards in early spring. Pest taxa included primarily western flower thrips (Frankliniella occidentalis (Pergande)), Lygus spp., and tetranychid spider mites. Common predators included phytoseiid mites and minute pirate bugs (Orius tristicolor (White)). Sites that were geographically close to one another were not more similar (in taxonomic composition of overwintering arthropods) than more distantly separated sites

Tethered flight characteristics of male and female pear psylla (Homoptera: Psyllidae): comparison of pre-reproductive and reproductive insects

Volume: 71Start Page: 24End Page: 3

Reduction in feeding by diapausing and postdiapause pear psylla (Homoptera: Psyllidae) caused by extract from buffalo gourd (Cucurbitaceae)

Rates of honeydew production were lower in diapausing winterform pear psylla, Cacopsylla pyricola (Foerster), than in psylla brought out of diapause by exposure either to long-day conditions or to an insect growth regulator (fenoxycarb). An extract obtained from a nonhost species, buffalo gourd (Cucurbita foetidissima HBK.), caused reduced honeydew production when misted onto pear shoots. Reductions in feeding were as pronounced in diapausing insects as in psylla that were in a postdiapause condition. Ovarian development scores were positively correlated with honeydew production, indicating that feeding deterrents may be useful for delaying the onset of egglaying in the field.Key words: Insecta; Cacopsylla pyricola; diapause; honeydew production; feeding deterren

Sticky trap catch of winterform and summerform pear psylla (Homoptera: Psyllidae) over non-orchard habitats

Volume: 71Start Page: 176End Page: 18

Identification of three new ‘Candidatus Liberibacter solanacearum’ haplotypes in four psyllid species (Hemiptera: Psylloidea)

Abstract Eleven haplotypes of the bacterium, ‘Candidatus Liberibacter solanacearum’, have been identified worldwide, several of which infect important agricultural crops. In the United States, haplotypes A and B are associated with yield and quality losses in potato, tomato, and other crops of the Solanaceae. Both haplotypes are vectored by potato psyllid, Bactericera cockerelli. Recently, a third haplotype, designated F, was identified in southern Oregon potato fields. To identify the vector of this haplotype, psyllids of multiple species were collected from yellow sticky cards placed near potato fields during two growing seasons. Over 2700 specimens were tested for ‘Ca. L. solanacearum’ by polymerase chain reaction. Forty-seven psyllids harbored the bacterium. The infected specimens comprised four psyllid species in two families, Aphalaridae and Triozidae (Hemiptera: Psylloidea). Nucleic acid and/or amino acid sequence analysis of the ‘Ca. L. solanacearum’ 16S ribosomal RNA, 50S ribosomal proteins L10/L12, and outer membrane protein identified three new haplotypes of the bacterium, designated as Aph1, Aph2 and Aph3, including two variants of Aph2 (Aph2a and Aph2b). The impact of these new haplotypes on solanaceous or other crops is not known. The vector of ‘Ca. L. solanacearum’ haplotype F was not detected in this study