The only answer , as I'm not a scientist or expert on diseases is "all of
em" as its a multi purpose dust.
I don't know what causes the plants to get sick.
When I get my Diploma of Plant diseases, I could answer you.. As it is, I'm
as much in the dark as you are regarding the problems I have had in the
past.
I will take pictures if I see the diseases, and put them on the web, then
some one may know. The problem occurs as described previously..
It could be mildew /fungal problems or a virus disease transmitted by
thrips. It seem to happen later on into the season and they blacken and dry
out.
High humidity, lack of air movement seems to hasten the problem and tomatoes
are not very productive after that.
BTW, I am not as careful lwithe watering the plant as I should be as the
leaves often get wet and make contact with the soil...
PS I wish I did have that diploma.... but that all I can give you.

"Chookie" wrote in message
news:ehrebeniuk-9EEC45.22545607012009@news...
In article ,
"Jonno" wrote:

I have seen my tomatoes turn up their toes become very straggly and get
sick
like I described. If I knew the cause I would not be trying to prevent
everything..The Dusting powder is recommended to be applied every 5 to 10
days and is a multiple disease preventative..Unfortunately this had some
disastrous effects with the bees.

I am trying to find out WHICH diseases you thought you were preventing.
What
does this preparation prevent?

--
Chookie -- Sydney, Australia
(Replace "foulspambegone" with "optushome" to reply)

http://chookiesbackyard.blogspot.com/