BEE-L Archives

Informed Discussion of Beekeeping Issues and Bee Biology

BEE-L@COMMUNITY.LSOFT.COM

Options: Use Monospaced Font
Show Text Part by Default
Show All Mail Headers

Message: [<< First] [< Prev] [Next >] [Last >>]
Topic: [<< First] [< Prev] [Next >] [Last >>]
Author: [<< First] [< Prev] [Next >] [Last >>]

Print Reply
Subject:
From:
Aaron Morris <[log in to unmask]>
Reply To:
Informed Discussion of Beekeeping Issues and Bee Biology <[log in to unmask]>
Date:
Wed, 1 Oct 2003 09:26:24 -0400
Content-Type:
text/plain
Parts/Attachments:
text/plain (61 lines)
>> "There's always a cost to the organism [mites in this case]
>> in being resistant and if the selection
>> pressure, i.e. the treatment type, is removed then the
>> "normal" susceptible characters will once
>> again predominate in a population."

Or as we say in systems programming, "You tweak it here, you kick it there!"
In way of explanation, say a bee breeder crosses a certain breeder queen
with a desireable trait (say good honey production) with drones from a drone
production colony with a different desireable trait (say pretty color).  The
cross is successful and the breeder comes up with a batch of queens that
produce enormous crops of honey and thet're all a prettu color to boot.
Great!  It could however be the case that, unbeknownst to the breeder, the
combination of traits that yield the pretty, high production colonies also
resulted in the drones from those colonies being duds and unable to pass on
their genes.  Unless the breeder continues to cross the originals to keep
the trait going, the natural selection will eventually remove the resultant
strain (pretty bees that produce big crops).

Now it may not be that simple.  The original example was V. mites that are
resistent to acaricides (I think both Coumaphos and fluvalinate were
mentioned).  It could possibly be that the resistence that the mites build
up comes hand in hand with the mites being afraid of the dark.  Doubtful,
but hey, who knows?  So anyway, these resistent mites who are afraid of the
dark would rather leave the hive for a walk in the sunshine than enter a
dark cell with a ripe larvae.  If that were so, this strain of resistent
mites would soon cease to exist.  Perhaps they already have!  Yes, I
hypothesize that there have been two strains of resistent mites, one who
behave "normally" and continue Varroa reproduction cycles as we know them,
and one strain of resistent mites who walk out of the hive because they are
afraid of the dark and soon perish in the sun!  We haven't heard about the
afraid of the dark mites because they quickly perish.

So, you tweak it here, you kick it there.  It may be the case that the
pressure (be it bee breeder, or chemicals, or whatever) will have positive
results all around (the pretty bees are good producers and the drones are
verile studs), or it may be the case as described (good honey preducers,
pretty bees, sterile drones).  Once the pressure is removed, left long
enough to "natural" environments, things will return towards equilibrium
(what they were before any pressures were applied).  Such has been the case
over and over in the beekeeping industry when breeders have isolated traits
in a strain of bees, only to have those characteristics lost when the bees
are released to the general beekeeping population.  The Starline strain is a
prime example.  Such is the danger of SMR breeders.  Unless continuous
selection occurs, the pressure is removed and things will revert to
equlibrium.

So Peter asks, "How good is new?"  My answer is as good as it is when it's
new.  If it's REALLY good, the incentive to keep up the pressure will keep
things new.  My thoughts go to expensive queens able to resist Varroa,
produce good honey crops, and what the hell, pretty too.  I would gladly
shift my treatment costs, time and effort, (what $10 per hive?  more?) to
the price of "new" queens if they consistently exhibited as described.

Aaron Morris - thinking new thoughts!  Nah, they've been thought before.
>

::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
-- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and  other info ---
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::

ATOM RSS1 RSS2