"Oz" wrote in message
...
Mooshie peas writes
On Sun, 17 Aug 2003 17:54:49 +0100, Oz
posted:

Mooshie peas writes
On Wed, 13 Aug 2003 14:00:59 +0100, Oz
posted:

Mooshie peas writes
Of course, but it is a well known mechanism of resistance
development,
sub-lethal doses that leave the partially susceptible mutants still
alive. Antibiotic treatments are a case in point. The importance of
finishing the full course prescribed, and not stopping when you feel
better.

1) A reminder that bacteria are much simpler than insects, and with a
higher breeding rate.

Of course. But their biochemistry is quite similar, save for the speed
of generation change.

The plant genome is immense by comparison.

Yep, but the biochemistry is surprisingly similar.

No. A small subset is similar.

2) No farmer applies pesticides in the above mentioned manner anyway.
It varies from typically one to three applications per season.

Of course, again, economics plays a strong role. Antibiotics are taken
on the assumption that reinfection will not occur, whereas pests are
constantly returning.

Indeed. The aim is to prevent significant damage, not to eradicate the
pest for the season (except perhaps weeds).

Sure, the aim is to get as much crop for as little expense as
possible. With farsightedness, a smaller profit might be accepted for
a likely increased profit over the next decade. The aim with pests
might be to eradicate them forever but being pragmatic....

I know of no pests that have ever been eradicated, even in the heady
days when DDT worked very well.


The new worm screw worm fly has been pushed back from forays into Kansas to
the Panama canal using sterail male fly resases in large numbres. Females
only breed once. The have been errdicated from north america.

They lay the egg on a open wound and the maggog eats living flesh. Naval
cords are the wrost place for and infection. Somtimes one infestation will
kill a calf and two always will. Occasional some one will get in a fight and
the screw worm fly will lay eggs on a bloody nose. If the don't seek medical
help befeor the worms eat through to the brain they die very bad death.

The program started right after WWII the last out break that reach Oklahoma
was in 1972 and we have been pushing the as far away as we can get them into
the narrow isthmus of Panama to reduce costs.

Gordon