In a message dated 12/08/2008 22:51:03 GMT Standard Time,  
[log in to unmask] writes:

About  time before resistance sets in I have no idea. But I have decided not
to  change active principle till that happens.




If a beekeeper on such a large scale as you are uses Amitraz  on every  
colony every year, which seems to be what you are doing, then resistance is  likely 
to occur sooner rather than later. Why not use it in rotation with other  
pest management systems with a different mode of action?
 
Chris



   

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