Posted: 12/08/2012 at 10:32
Well, spuds are one of the major sources of the LB pathogen. It was the cause of the Irish potato famine, after all. The pathogen can also live on in diseased spuds, whereas, for whatever strange reason, it dies off with the host plant in tomatoes.
Toms are all equally susceptible to fungal problems of all kinds. There are claims being made of fungal-resistance in some hybrids these days but I don't believe it.
It's really only LB - of the fungal and bacterial problems - that requires yanking and destroying a tom plant. I fear that some growers in this forum could be yanking plants unnecessarily. Plants will cope pretty well with the likes of Early Blight, Septoria Leaf Spot, and the like. The leaves won't look very nice, but, with basic housekeeping practices, it will take a dang long time for the disease to affect the fruit and/or kill the plant. In fact, the plant usually dies a natural death from end-of-season cold weather before disease kills it.