tomato problems

Citation: www.potato.org.uk/media_files/FAB_GAs/what_is_potato_blight_v5.pdf

The genetic population of the pathogen is ever changing but until the 1970s in Britain there
was only one mating type. New findings have shown that a new dominant strain, called blue
13, is more aggressive and fitter than most other strains. Potato Council is conducting new
research to identify the differences between strains and the possibility of these strains mating to
give oospores, which are a third type of P. infestans spore. These are thick-walled spores that
can survive in soils over long periods.

Aunty has added the citation to the post for you Fatcat.  That's where it should be

www.potato.org.uk/media_files/FAB_GAs/what_is_potato_blight_v5.pdf
How's that yorkie?

and the possibility of these strains mating to give oospores

Says they are investigating the possibilty of them doing so.

Doesn't say that have done.

www.actahort.org/books/834/834_5.htm      Try this then.

So it can overwinter in soil then?

Thnaks for this debate.  I know a lot more know... the picture I am getting is that blight is probably all around, but only flares if conditions are right (and then its pretty destructive).  Some prefer drip or soil level watering for tomatoes, not overhead sprinklers (and this might be good for tomatoes as it can avoid the blight conditions).

That even if the blight is active and all around you can sometimes mysteriously escape getting it.

There's some debate about whether and how spores survive in the soil, (but maybe this doesnt matter so much if blight is all around anyway?).   That good practice like destroying ie not composting the blighted plants is helpful, and crop rotation probably helps too.

That having blight is not necessarily the end of the world because if you treat the plants (commercial or homemade spray) you will get some crop.  And you wont loose a seed line because you can save seed free of blight from infected tomatoes.

Its all good.Pip