[tomato] Blights
Byron (Tomato@GlobalGarden.com)
Fri, 9 Jul 1999 11:30:56 -0400
Thomas
Sorry forgot to answer your question
Yes I have heard about phytophthora on tomatoes.
Some seed inspection companies test for it.
phytophthora has several types of infections
1. Crown/root rot
2. Stem rot
3. leaf rot
4. fruit rot.
Crown or root rot is usually noticed on the soil line, The plant above the
soil line appears fine except it turns black at the soil line
Stem rot, affects the branches and growing point. Makes a small circle
the stems above it falls off the plant. On the remiander of the plant stem
there
is a 1/4 to 1/2 in black/dark brown area.
Leaf rot. The leaves turn black and fall off leaving only the branches and
stalk.
Fruit rot. It starts at the stem end and turns the fruit black, If you cut
open the fruit, it really stinks.
This disease usually doesn't start until after a lot of rain usually >2 in.
This disease can be seed, or soil borne or can be transmitted by bugs.
So far in tomatoes, all I have seen is seed borne, in that if affected only
one variety in the garden and not the others. Seeds were not chlorine
or fungus treated.
Byron