From: Dan Levin <levin at pixar.com> on 2004.07.06 at 22:22:45(11724)|
Thanks for adding a new/ thoughtful dimension to the fray. I've no
doubt that fungus gnat larvae absolutely engage both as the primary
invader and as a vector for fungal infection in many cases. Fungus
gnats are, in my opinion, an insidious pest generally underestimated/
overlooked by hobbyist growers. This is a mistake- considering the
potential for serious damage by the largely unseen larval stages.
I still hold by my observation (pestilent postulate?) that in my modest
greenhouse anyway, rotting conditions invite fungus gnat larvae to
infect otherwise dormant araceous tubers and corms. The areas of
rot are consistently too pronounced & developed, and the number of
embedded larvae too few (generally just one or two) when problems
are first detected. But who knows - I could absolutely be wrong..!
Whatever the actual sequence of infection, the take-aways here are:
1) Soggy, stagnant conditions & non actively growing aroids don't mix.
2) On the subject of fungus gnats, the grower must be vigilant and take
immediate corrective action to avoid losses and/ or disease transmission.
3) For the haute cuisine alternative, write Neil for gourmet recipes : )
Best to all,
Phil Diamond wrote:
> On Sun, 4 Jul 2004, Dan Levin wrote:
> > in a public forum, that these fungus gnat larvae are more akin
> > to a nasty secondary infection and are rarely if ever the primary
> > causal agent.
> Locally, a commercial grower was having, for the first time, unacceptable
> losses from fungal infection after deflasking orchid seedlings into
> community pots. Finally, he brought in the government agricultural extension
> experts who diagnose it as the gnats, with the fungi entering from root
> damage. So, he sprayed with insecticide rather than fungicide and his
> problem disappeared. So, which is primary and which secondary?
> Cordially, Phil