Dick Allen says: "One of the reasons, it is claimed,
mites became resistant to Apistan is that beekeepers
were overusing the strips."
Few years before it was published in one of American
bee journals, I learned about the method for testing
of resistance to contact acaricides from scientists at
German beekeeping institutes. (The metod is simple:
just extract some varoa from brood (drone) and drop it
to walk one minute on antivaroa strip. They should be
dead in short time - if no present resistance, or some
of them will be showing sings of life (partial
paralyses) if they are in process of becoming
resistant, or will be totally alive - if resistance is
big.)
In my country (Macedonia) we have had a lot experience
with resistance, because we have had it 15 years ago
with amitraz and after that we learned to exchange
active substances and methods of application in
treatments made in same year, or in next, which is
usually a must.
So what happened when I was testing my varroas on
their resistance to fluvalinate - the signs of
resistance was non existing.
You should know that for many years I use same scheme
for fighting against varroa:
- in August, before brood of winter bees, I am using
only half dose of fluvalinate (on wooden sticks) for
colonies witch are all on full open mesh bottom
boards.
- waiting for end of season in mountains (around 1000
meters) to facilitate early ceasing of brood rearing
- one treatment in broodless period with different
active substance (fumigation with amitraz or
fluvalinate or dripping with systemic - for instance
Apitol, in the past, or in recent years: dripping
solution of oxalic acid)
If I am located on isolated place with my winter
beeyard (no neighbor beeyards) in many years I was
able to skip August treatment.
My successful philosophy against varroa was: it is
never necessary to kill near 100% of mites. August
treatment is important to save wintering bees by just
killing excessive numbers of mites (which are jumping
from drone to worker brood). Winter (or late autumn)
treatment is much more important, and here oxalic acid
is the best!
I fill that whatever mild treatment are used in
August, it will have high antiresistance properties if
open screen mesh floors is used. Also, I fill that
real IPM is not a option, and I had never count
natural mite mortality because of so many variables
involved.
Now, I am little surprised that this kind of
philosophy are becoming mainstream in Europe
antivarroa fighting.
For more read:
http://www.apimondia.org/apiacta/articles/2004/mutinelli_1.pdf
Regards,
Aleksandar Mihajlovski
Republic of Macedonia
____________________________________________________
Start your day with Yahoo! - make it your home page
http://www.yahoo.com/r/hs
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
-- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info ---
::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
|
