[Americasbeekeeper]

Effect of Larvae Treated with Mixed Biopesticide Bacillus thuringiensis - Abamectin on Sex Pheromone Communication System in Cotton Bollworm, Helicoverpa armigera
Biopesticide usage is increasing every year, even more with the prespective that mixtures of pesticides are theoretically more effective in delaying resistance than alternating usage of pesticides [24]. An example of this strategy is the conjugation of the toxins from Bacillus thuringiensis with the toxin of abamectin, to form a new biopesticide called BtA [25]. This BtA mixture has been widely used to control agricultural pests [26]–[28] and the usage of BtA was in the hundreds of tons in several provinces of China in 2011. Many researchers have demonstrated that pesticides impact natural enemies directly or indirectly [4]–[11]. The longevity of Microplitis mediator, a parasitoid of the cotton bollworm (Helicoverpa armigera) decreased significantly after being fed with 10% honey water containing a sublethal dose of a Bacillus thuringiensis and abamectin (BtA) [10].
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068756

 

[Ray]

Yet again, the unintended consequences jab you in the ahh..backside. I am beginning to think that Mother Nature enjoys a challenge.

 

[Americasbeekeeper]

So often beekeepers forget bees are insects too.

 

[tecumseh]

I am not certain what the link to honeybees might be? Would anyone intentionally feed BT to larvae honeybees?

 

[Americasbeekeeper]

BT is used by some beekeepers to control wax moths. Yes they do unintentionally feed Bt to bee larvae. In combination with products bees bring in foraging , fungicides, insecticides, adjudavents, and antibiotics, it can be lethal.

 

[Iddee]

The mixture can also be lethal without the BT, so who is to say the BT is at fault?

 

[Lburou]

I wonder where they got the honey and how they know there was no contamination in their 10% honey feeding solution. I am certain however, that we affect our environment in ways we will never know in order to live the way we do . I'm not sure whether or not these study results should be generalized to honey bees. I guess the dose of BT we put on empty frames is important.....May be one of those times when more is not better. Wax moths and small hive beetle are severe threats in my area, so, using BT is worth the risks. I'm pretty sure my drone bees aren't interested in the mating pheremones of the cotton bollworm anyway.

 

[Gypsi]

After my little run with EFB I suspect I'll be making more candles and using less BT regardless of its effectiveness at wax moth control. Last year I had NO wax, so I used what I found in the old bee tree to give the bees a start. In the future I'll be giving them empty frames and sugarwater.

State Bee inspector says he only saw 3 cases of EFB, but in my local group most people don't invite him to visit at all.. I'm not buying that I'm the only one that had problems.

 

[tecumseh]

well actually Gypsi as far as I can tell in some years Efb is quite common but most folks don't sweat bullets over that small problem. with a good flow and an improvement in nutrition for the great majority of folks efb simply disappears.

simply sounds to me like someone is creating a connection where one does not exist. such statements as 'bees are insects' too suggest someone has missed a couple of important lessons along the way.

I do not claim to be an expert on Bt nor do I use Bt... although if the need came along I would much more likely to use this than anything else out there on the market for wax moth control... it is my understanding Bt comes in several variation and is fairly species specific. ALWAYS it is important to not only ask the question as to how are things are the same but also how they are different <this is not the end of the journey but certainly it is the beginning.

 

[Gypsi]

Tec,

If efb disappears during a good flow with a good and busy queen, does the residual bacteria left in cells from the feces of infected brood also disappear and not present contagion in future years?

Because if it doesn't disappear, I won't ever be storing much wax, I lost over half of my hives to this.