Worldwide Beekeeping
Beekeeping => General Beekeeping => Topic started by: Jen on July 18, 2016, 11:18:49 pm
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What is it? ~snork~
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I would use it but cannot until it is allowed here in Canada. :sad:
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perry-i thought Canada allowed bt.
it's used to control wax moths as it kills the larva. Michael bush has said that he sprays it on comb while bees are on it with no ill effects. I have used it on some frames & not others so I can compare the results. I also found a study that says it 'might' help with varrora destructor
ABSTRACT: This paper reviews prospective biological control agents of the varroa mite, Varroa destructor n. sp. (Acari, Mesostigmata). This ectoparasite has caused severe damage to populations of the European honeybee, Apis mellifera , world-wide in recent years. To date, no promising natural enemies of varroa species have been identified on A. mellifera or its original host, Apis cerana . Therefore, biological control will probably require natural enemies from other hosts. The following groups of organisms were reviewed as potential biological control agents: predatory mites, parasitoids and entomopathogens (nematodes, protozoa, viruses, Bacillus thuringiensis , rickettsiae, and fungi). The candidate groups were ranked according to their lethality to Acari, likely ability to operate under the physical conditions of honeybee colonies, ease of targeting, and ease of mass-production. Preferential consideration was given to the natural enemies of Acari that occupy taxonomic groups close to varroa. Entomopathogenic fungi, which kill a wide range of acarine species, were identified as prime candidates for screening against varroa. Bacillus thuringiensi s also requires study, particularly strains producing novel toxins active against non-insect hosts. Entomopathogenic protozoa and nematodes show less potential for varroa control, but nonetheless warrant preliminary investigation. We consider predators, parasitoids, viruses and rickettsiae to have little potential to control varroa. Because the physical conditions within honeybee colonies are similar everywhere, it is very likely that a biological control agent of varroa could be used successfully throughout the world.
https://en.wikipedia.org/wiki/Bacillus_thuringiensis
http://www.entsoc.org/PDF/Pubs/Periodicals/EE/EETOCS/PDF/en069901172p.pdf
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Bacillus thuringensis has a number of racial varieties that produce a pesticide (biopesticide) that kills a target pest. Racial varieties have been developed for mosquitoes, beetles, moths, etc. My wife used to be the QC supervisor (ran lab tests to evaluate the efficacy of different batches) they produced in Wasco, CA. When they harvested the huge vats, the entire town smelled really bad. I don't use it. I let my bees rob out comb so it is stored dry and I make sure there is ample sunlight available to make my combs unattractive to moths.
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It's available in the USA for cabbage loopers and other larvae.... Local product name Xentari
Stable in powder form for years, must be used within 24 hrs once mixed.
Kills them loopers quickly ;D
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Chip "Bacillus thuringensis has a number of racial varieties that produce a pesticide (biopesticide) that kills a target pest. Racial varieties have been developed for mosquitoes, beetles, moths, etc."
So, is BT a chemical?
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Jen, BT is spores. When eaten by a wax moth larva, it hatches and begins eating the larva from the inside.
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The poisoning isn't from the spores per se. Bacterial spores, in this case BT, is what's in the stuff you buy and treat with. After application, those spores release (usually by consumption but there may be varieties that work in other ways?) an endotoxin that kills a specific pest, be it a mosquito, cabbage looper or a wax worm--depends on the racial variety of BT. So, it is a pesticide but one that targets specific insects. The folks that make it refer to it as a biological insecticide and that seems accurate--it just works a little differently than others. That said, the poison works just like in most other bacteria that cause death or make you sick. Botulism is a good example. Spores of botulism are on everything we touch, and in many cases consume, but you only get sick (or die) under circumstances that let those spores release the toxin. We pressure can meats and low acid foods to kill the spores because the medium (stuff you're canning) provides the proper environment for the spores to release their toxin. Botulism is one of those toxins that is extremely strong--like a teaspoon in water could wipe out an entire town kind of bad! It's so toxic that determining the cause of death is difficult (for example, crib death--it wasn't that long ago that practitioners had no idea why kids would die but now we know not to give infants honey because botulism spores are everywhere and a kids gut can have the right medium for spores to release toxin) and it has delayed the diagnosis of many deaths over the years. It's a chemical, just not a synthetic one. All that said, I don't think BT is bad; it's certainly gained a rightful place in the control of many insects because we can target which ones it will kill and which ones it won't.
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Will the variety used for cabbage loopers and hornworms work for wax moth larva?
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Don't know. When my wife worked in that field, they had a race for mosquitoes (also killed midges which are beneficial) and another for loopers and I think it also worked on a corn worm but don't recall the specifics
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The BT for cabbage loopers does work for wax moths. BT Aizawai.
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Thanks Iddee :)
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BT is sooooo easy, and it brings a bit of insurance. I don't have a place to store used bee equipment that is "moth proof."
lazy
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I've heard to set a bowl of vinegar is a sealed stack of hives, anyone try that?