Metarhizium, middel tegen varroa.
Geplaatst: vr 22 okt 2004, 11:59
Een soort zwam als bestrijdingsmiddel tegen varroa. Hier heb ik het stukje vandaan: http://www.ars.usda.gov/is/AR/archive/o ... es1004.htm
Ik heb het relevante stukje eruit gehaald (vertaling staat eronder):
Since 2000, scientists in the ARS Beneficial Insects Research Unit (BIRU) at Weslaco, Texas, have been looking for a disease-causing agent, or pathogen, that can stop Varroa mites. The mite has developed resistance to the only approved chemicals'”fluvalinate and coumaphos'”now used for control, and coumaphos is on the U.S. Environmental Protection Agency's "hit list" for possible removal from the market. So the researchers have looked at various disease agents, tried different dosages and application methods, and conducted toxicity tests. Finally, they selected a strain of the fungus Metarhizium anisopliae that was highly pathogenic to Varroa mites.
This potent fungus, which also kills termites, doesn't harm bees or affect their queen's production. To test it, the scientists coated plastic strips with dry fungal spores and placed them inside the hives. Since bees naturally attack anything entering their hives, they tried to chew up the strips, spreading the spores throughout the colony.
In field trials, once the strips were inside the hives, several bees quickly made contact with the spores. Within 5 to 10 minutes, all the bees in the hive were exposed to the fungus, and most of the mites on them died within 3 to 5 days. The fungus provided excellent control of Varroa without impeding colony development or population size.
"We tried to find a pathogen of Varroa, and we did it!" says ARS entomologist Walker A. Jones, research leader of the BIRU. Tests showed that Metarhizium was as effective as fluvalinate, even 42 days after application. "Commercial beekeepers are very edgy about using fluvalinate and coumaphos and are eager to see this natural control get to market," Jones says.
This research was begun by Rosalind James, formerly with the Weslaco unit. Lambert H.B. Kanga, former BIRU research associate and now chair of the Entomology Department at Florida A&M University at Tallahassee, continues to collaborate on the project. "While Metarhizium doesn't kill as fast as fluvalinate and coumaphos, the result is the same," Kanga says. "Metarhizium gets the job done, and we won't have to worry about Varroa becoming resistant to the fungus."
Nu dan de vertaling:
Sinds 2000 zijn wetenschappers van de ARS Beneficial Insects Research Unit (BIRU) in Weslaco aan het zoeken geweest naar een ziekteveroorzakend middel of ziekteverwekker, die de Varroa mijten kan stoppen. De mijt heeft resistentie ontwikkeld tegen de enige toegelaten chemicaliën -fluvalinate en coumaphos '“ nu gebruikt voor beheersing, en coumaphos staat op de 'lijst'
Ik heb het relevante stukje eruit gehaald (vertaling staat eronder):
Since 2000, scientists in the ARS Beneficial Insects Research Unit (BIRU) at Weslaco, Texas, have been looking for a disease-causing agent, or pathogen, that can stop Varroa mites. The mite has developed resistance to the only approved chemicals'”fluvalinate and coumaphos'”now used for control, and coumaphos is on the U.S. Environmental Protection Agency's "hit list" for possible removal from the market. So the researchers have looked at various disease agents, tried different dosages and application methods, and conducted toxicity tests. Finally, they selected a strain of the fungus Metarhizium anisopliae that was highly pathogenic to Varroa mites.
This potent fungus, which also kills termites, doesn't harm bees or affect their queen's production. To test it, the scientists coated plastic strips with dry fungal spores and placed them inside the hives. Since bees naturally attack anything entering their hives, they tried to chew up the strips, spreading the spores throughout the colony.
In field trials, once the strips were inside the hives, several bees quickly made contact with the spores. Within 5 to 10 minutes, all the bees in the hive were exposed to the fungus, and most of the mites on them died within 3 to 5 days. The fungus provided excellent control of Varroa without impeding colony development or population size.
"We tried to find a pathogen of Varroa, and we did it!" says ARS entomologist Walker A. Jones, research leader of the BIRU. Tests showed that Metarhizium was as effective as fluvalinate, even 42 days after application. "Commercial beekeepers are very edgy about using fluvalinate and coumaphos and are eager to see this natural control get to market," Jones says.
This research was begun by Rosalind James, formerly with the Weslaco unit. Lambert H.B. Kanga, former BIRU research associate and now chair of the Entomology Department at Florida A&M University at Tallahassee, continues to collaborate on the project. "While Metarhizium doesn't kill as fast as fluvalinate and coumaphos, the result is the same," Kanga says. "Metarhizium gets the job done, and we won't have to worry about Varroa becoming resistant to the fungus."
Nu dan de vertaling:
Sinds 2000 zijn wetenschappers van de ARS Beneficial Insects Research Unit (BIRU) in Weslaco aan het zoeken geweest naar een ziekteveroorzakend middel of ziekteverwekker, die de Varroa mijten kan stoppen. De mijt heeft resistentie ontwikkeld tegen de enige toegelaten chemicaliën -fluvalinate en coumaphos '“ nu gebruikt voor beheersing, en coumaphos staat op de 'lijst'