28 research outputs found
Recommended from our members
Potato psyllid vector of zebra chip disease in the Pacific Northwest : biology, ecology, and management
This publication addresses the emergent issue in the Pacific Northwest of a potato infection called zebra chip disease, vectored by the potato psyllid. Includes information on the bacterium, the biology of the vector, description of damage from both vector and non-vector psyllids, and most current research on management.Published June 2012. A more recent revision exists. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalogKeywords: potato disease vector, Bactericera cockerelli (Šulc), Candidatus Liberibacter solanacearum, potato psyllid, potato diseas
Recommended from our members
Assessing Potato Psyllid Haplotypes in Potato Crops in the Pacific Northwestern United States
The potato psyllid, Bactericera cockerelli (Šulc), is
a vector of the bacterium ‘Candidatus Liberibacter
solanacearum’ (Lso) that has been linked to the economically
devastating zebra chip disease of potato. To date, four haplotypes
of the potato psyllid have been identified and include
Central, Western, Northwestern, and Southwestern haplotypes.
Zebra chip was reported in potato crops in the Pacific
Northwestern United States for the first time in 2011, and the
Lso-infected psyllids collected from zebra chip-affected fields
were identified as the Western haplotype. Additional studies
have reported a mix of the Western and Northwestern psyllid
haplotypes in the Pacific Northwest. The present study further
examined psyllid population dynamics over the duration of
the 2012 potato season in the Pacific Northwest by haplotype
analysis of 864 potato psyllids collected from potato fields in
Washington, Oregon, and Idaho. In the Yakima Valley of
Washington and the lower Columbia Basin of Washington
and Oregon, the Northwestern haplotype was predominant
(78%), and was detected earlier in the season than the
Western haplotype. Interestingly, in south-central Idaho, all
four psyllid haplotypes were identified, but the predominant
haplotype was the Western haplotype (77%). Here,
Northwestern psyllids were detected early in the season from
June to mid-August, whereas Central psyllidswere detected in
late July and thereafter. These results suggest that haplotype
composition of psyllid populations in potato fields throughout
the 2012 growing season in south-central Idaho differed greatly
from those in Washington and Oregon. Additionally, all
psyllids were analyzed for the presence of Lso, and no Lso-positive
psyllids were found in Washington and Oregon,
whereas Lso-positive psyllids were found in south-central
Idaho. These Lso-positive psyllids consisted of the Western,
Northwestern, and Central haplotypes
Sesquiterpenes of nine european liverworts from the genera, Anastrepta, bazzania, jungermannia, lepidozia and Scapania
[[abstract]]The essential oils of fourteen liverwort specimens from nine species of the Jungermanniales have been examined as to their sesquiterpenes. The barbatenes prove to be present in detectable amounts in all but one species. Bazzanene is frequently found with the barbatenes and new chemical evidence does not support the previously assigned structure but is consistent with a structure diastereomeric to trichodiene. This is consistent with a biogenetic rationale for the barbatene skeleton. Anasterptene, a novel crystalline tetracyclic hydrocarbon, has been found in numerous oils, and chemical degradation established a common skeleton with myliol. The samples of genus Scapania elaborate sesquiterpenes of the enantiomeric humulene-longifolene sequence. New members of this group found are (−)-β-longipinene, (−)-longipipanol, and (+)-γ-himachalene. The related germacrene series is represented by a cadinene, (−)-α-ylangene, and (−)-sativene. A series of cis-fused selinenes have also been found, which are more closely allied to the germacrene-sativene group than to typical trans-fused selinenes. One of these selinenes is shown to be the same as the material previously designated as sibirene. Scapania undulata also elaborates (+)-α- and β-chamigrene, and a number of novel hydrocarbons of still unknown structure.[[notice]]補正完畢[[incitationindex]]SC