To: North American Fruit Explorers <nafex@lists.ibiblio.org>
Subject: Re: [NAFEX] PC survival in apples and a question about Assail
Date: Tue, 10 Feb 2009 22:30:17 -0500
That makes sense. As I think more and more about what I see in my
apples, I'm starting to doubt the idea that apples grow and crush the
curculio larva. It seems to me that if the larva penetrated into the
apple and then got crushed, there would have to be at least a tiny dead
area under the scar. I don't remember that. It seems to me that the
curculio scars are truly only skin deep. (I'll pay more attention to
that in the future.)
Perhaps when we see mature apples with those scars, it's because either
there was no egg, or the egg failed to hatch, or something happened to
the larva before it could penetrate the fruit. (That something could be
the weather, a predator, or the spray we used.) Perhaps the apples that
had successful larval development all fell to the ground when they were
small.
Steve in the Adirondacks
Mark Angermayer wrote:
We don't seem to have a lot of curculio here, but everything I've read
indicates it can reproduce in apples. It emits a substance (maybe
ethylene?) that tricks the tree into dropping the fruit.