Re: Leaf spot
In a message dated 10/02/97 19:40:30, Bill says:
<< I still have difficulty seeing how fungal leaf spot can be spread by
aphids. Without confirmation I think I'll stick to the traditional view
that the spores are airborne and splashed from plant to plant by rain.
I'm sure there was some research done over here (not on iris) showing how
aphids and other insects act as vectors for fungal and bacterial diseases by
carrying the spores and bacteria around on their little feet and in their
little mouths - just as you or I carry mud from the garden into the house on
our boots (and don't we get to hear about it!).
I must say that they act only as a vector, and merely make the problem worse.
Getting rid of the bugs will not get rid of leaf spot.
Graham Spencer, UK