"Aside from questions of cost and yield, general IPM principles tell us that using any pesticide (or antibiotic) constantly, at low levels, and across large populations will lead to the selection and spread of resistant strains"

This statement is only sort of true.  Resistance always depends on the organism having some tiny amount of ability to metabolically degrade or perhaps avoid exposure to the toxic substance.  Take DDT and flies as an example.  Flies had a metabolic pathway to degrade chlorinated organics before DDT ever came along.  When exposed to DDT at normal use concentrations a tiny number of flies survived due to this pre-existing metabolic pathway.  In those survivors the pathway was a bit more robust than normal.  Mutations rapidly occurred that strengthened that metabolic path and rapidly it got to the point you could paint flies white with DDT and they survived.  Contrast the fly situation with mosquitoes.  Mosquitoes totally lacked the metabolism to deal with chlorinated organics.  In spite of 75 years of use in some places for mosquito control I am not aware of any resistance happening in this species.  Now, I will be the first to admit I have not read the science on mosquitoes for some years so perhaps some minor resistance has been seen.  But, if so it is drastically less robust than in flies and far, far slower to develop.

We do have examples of pesticides that have been in use for a very long time without resistance showing up.  The fungicide chlorothalonil is one example.  This is a preventative, non systemic fungicide.  As such it requires repeated sprays at intervals of ten days to two weeks to protect new growth.  It has been used this way on bananas and peanuts since the 1960s without resistance showing up.  This does not mean resistance can never happen.  Who knows what some new mutation will do tomorrow? 

Or consider oxalic acid on mites.  I have heard many say mites will never become resistant due to its mode of action.  Well, I am not so sure we really know its mode of action for starters.  If the idea that it acts by attacking tender foot parts what is to prevent the mite from mutating to a more dense chitin foot covering?  Such a change might be slow.  And might well not give as great a resistance as a robust metabolic degradation pathway.  But, I sure can not say it could not happen.  It also is possible bees would evolve right along with mites and as mites tolerated higher doses so would the bees.

Dick


" Any discovery made by the human mind can be explained in its essentials to the curious learner."  Professor Benjamin Schumacher talking about teaching quantum mechanics to non scientists.   "For every complex problem there is a solution which is simple, neat and wrong."  H. L. Mencken

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