Date: Mon, 8 Nov 1999 16:46:26 -0500 From: "Malouf, Perry" <Perry.Malouf@jhuapl.edu> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg3753$foo@default> Subject: FW: orthene and N. gracilis scale
Andrew Marshall posted an interesting protocol for spraying Nepenthes
with systemic pesticides. The information he presented brought a
few questions to my mind, and I hope Andrew (or someone else)
might comment.
>
The protocol involved cyclic applications of pesticides with a
periodicity of 7 days:
> In 7 days, check again ...In 7 days repeat with the orthene/soap....
> In 7 days, examine the plant. Is there ANY bugs on it? If so,
repeat...
>... You must get the newly hatched buggers before they lay eggs again.
> Since most of these sprays do nothing for eggs, you must follow the
> hatch schedule. 7-10 days is it.....
My question is: how long does a systemic (such as Orthene) remain in
lethal concentrations in the treated plant? If lethal concentrations remain
in plant tissues for appreciably longer than 7 days then I wonder if it is
necessary to treat the plant with a periodicity of 7 days.
There was also mentioned the idea of using a different systemic with the
Orthene, in alternating fashion, so that pesticide-resistant bugs wouldn't
develop.
Have bugs developed a resistance to Orthene? Does it happen commonly?
That's a scary thought! So far, Orthene has killed any infestations in my
Nepenthes
and orchids and I haven't had to implement a follow-up treatment within 7
days.
I point out, however, that when I spot an infested plant then the whole
collection
will receive the treatment. It does no good to treat an infested plant and
leave
the others to harbor the pest. This would provide ripe opportunity for a
reinfestation.
Regards,
Perry Malouf
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