Repository logo
 
Publication

Field and laboratory testing for amitraz-tolerant varroa populations. How comparable are their results?

dc.contributor.authorPires, Sancia
dc.contributor.authorPereira, Óscar
dc.contributor.authorMurilhas, António
dc.date.accessioned2011-06-09T13:38:37Z
dc.date.available2011-06-09T13:38:37Z
dc.date.issued2007
dc.description.abstractPortuguese beekeepers have frequently used amitraz (Apivar, Acadrex) in an attempt to cope with Varroa. As a result of beekeepers’ claims of an alarming decrease in amitraz field treatment efficacy, a nation-wide screening project was launched to ascertain the merit of those claims and, eventually, introduce changes in the way state institutions were interacting with beekeeping associations and beekeepers. Approximately 4.000 colonies were field-tested (following a similar approach to the “British National Bee Unit” fluvalinate field testing methodology) against blank control tests (without amitraz strips). From those colonies, 1579 allowed conclusive testing (i.e. where no less than 4 Varroa per honey bee colony were tested). Out of these colonies 272 were considered to host amitraz-tolerant Varroa populations (using, as border line, 80 % of amitraz induced Varroa mortality). Laboratory testing followed the methodological approach of determining amitraz average lethal times (LT50) for Varroa. Twenty two brood samples, taken from colonies where field testing had resulted positive for amitraz-tolerant Varroa populations, were brought in for laboratory testing. A probit analysis showed that the LT50 were 34,8 ± 3,7 and 28,4 ± 3,5 minutes for susceptible (control) and amitraz-tolerant Varroa groups, respectively. Considering both the regression coefficients and slopes of probit vs. log10 of these two groups, it is manifest a relatively low heterogeneity (P> 0,05) between groups of Varroa originating from susceptible vs. amitraz-tolerant populations. We discuss what might have contributed to this somehow expected situation.por
dc.description.sponsorshipINGA - Programa Apícola - Acções de Melhoria da Produção e Comercialização dos Produtos Apícolaspor
dc.identifier.citationPires, Sância; Pereira, Óscar; Murilhas, António (2007). Field and laboratory testing for amitraz-tolerant varroa populations. How comparable are their results? In 40th Apimondia International Apicultural Congress. Melbournepor
dc.identifier.urihttp://hdl.handle.net/10198/5094
dc.language.isoengpor
dc.peerreviewedyespor
dc.publisherApimondiapor
dc.relationEstudo sobre a eficácia actual do “Apistan” e do “Apivar” na luta contra a varroose em Portugalpor
dc.relation.publisherversionwww.apimondia2007.compor
dc.titleField and laboratory testing for amitraz-tolerant varroa populations. How comparable are their results?por
dc.typeconference object
dspace.entity.typePublication
oaire.citation.conferencePlaceMelbourne Australiapor
oaire.citation.endPage141por
oaire.citation.issueNº 212por
oaire.citation.startPage141por
oaire.citation.title40th Apimondia International Apicultural Congresspor
person.familyNamePires
person.givenNameSancia
person.identifier.ciencia-idCC12-1B38-26C8
person.identifier.orcid0000-0001-8427-0179
person.identifier.scopus-author-id53878422600
rcaap.rightsopenAccesspor
rcaap.typeconferenceObjectpor
relation.isAuthorOfPublicationd1319f5d-6ffc-4e2c-9035-fa06b834c88f
relation.isAuthorOfPublication.latestForDiscoveryd1319f5d-6ffc-4e2c-9035-fa06b834c88f

Files

Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
Field And Laboratory Testing for Amitraz-.pdf
Size:
455.2 KB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description: