In article ,
Pam Moore wrote:
On 25 Aug 2003 11:23:22 GMT, (Nick Maclaren) wrote:

Blight certainly can cause yellowing, but it would be flabberghasting
if you had an infection just starting now! The humidity has been low
for a month, and blight needs high humidity for transmission.

See my separate post about tomatoes. I'm SURE it is blight; the fruit
are affected too, so the lack-of-rain theory is not infallible, though
we have had drizzle here in the early hours for the last 4 days.

That could cause the necessary high humidity, but I don't know how
tomatoes behave w.r.t. blight.

Ignore the "crop rotation" solution - blight overwinters on many
common weeds, and is borne by the wind. I had Pink Fir Apple wiped
out one year, and had no trouble on other varieties in subsequent
years (though I do spray, erratically).


Regards,
Nick Maclaren.