Re: Iris genetics, reproduction, and disease
Quite a while ago, Donald said ->
> micorhizal fungi .... or to protect their roots from bacterial infections
(rots) or invasion >from other fungi. If there are soil fungi which are
naturally associated with the
>roots of irises, then the fungi may be playing a role in increasing plant
>vigor or preventing bacterial or fungal root rots.
At our last local club meeting, our speaker was a plant pathologist from the
University extension program, Dr. Beth...(it will come to me eventually).
She gave a really interesting presentation - among other things, bacterial
diseases can be recognized from the pattern/color of death on the leaves and
are different from fungal diseases. She said the bacterial rots always have
a yellow zone between the live green and dead brown. Worse news, she says a
common source of rot to the roots and rhizome is infection of the leaf tips
which then allows the bacteria to work their way down the leaf to the roots.
The good news is that keeping dying leaves trimmed is an effective control.
So, it makes a lot of sense that cold or drought injury to leaf tips would be
a major source of rot problems. I also suspect that bits of mowed grass
being slung into foliage can cause enough injury to allow rot in if health is
shaky - I have suspected weed eating particularly as a problem.
So, my point is, Donald, that roots may not be how soft rot enters the plant.
She also showed a picture of crown rot, which just looked like a really bad
case of soft rot.
Linda Mann firstname.lastname@example.org e tenn usa rot central