I am having the SAME issue with my pole beans. In fact, not only are they turning yellow, but sometimes have brown crinkly spots. Usually, just yellow though. I just made a post about it. Anyone else have thoughts? How long have your tomatoes been yellowing at the bottom? I have a terrible problem with early blight every year. It usually starts in May very subtle. It starts on the bottom and moves up. The leaves turn yellowish and get brown crispy spots and then eventually just shrivel up. It moves up throughout the year and eventually most of the plant will be yellow. So, even though it's called "early blight" (because it STARTS early in the season, as opposed to late blight), it does most of its damage later in the year. Mine get it every year. This year I used daconil and it helps. Take a look at my previous posting from earlier today. I have a pic of my beans. Is that what you're having too?

For Florida, I would recommend the variety "3-feet-plus" (from Evergreen Y.H.). It was sent to me by a trader from Florida, where it had done well. Through an accidental observation, I might have found out why - it seems to have some resistance to salt in the soil. I planted it on a plot where a pool had been drained previously, and other yardlongs (and other vegetables) had languished... "3-feet-plus" produced heavily. The beans are very firm in texture, and have good flavor.

Are the pole beans and peas shading the beans? Another thought --maybe the tall things have a bigger root system and are soaking up all the nutrients from the bush beans. If the tall things are not shading the bush beans, then give the beans a few doses of something like manure or compost tea

Maybe Downey Mildew (based on just that one leaf in the center) but can't be sure from the photo. You can Google lots of pics of it to compare to your plants. I would also check the undersides of the leaves carefully as aphids and especially spider mites can have that same effect on leaves. Dave