Zucchini & Tomato Dying
Both plants were thriving until 4 days ago. These white fuzzy spots on both plants are killing them from the bottom up. And it's spreading quickly. Thank you for any help you can offer.
Zucchini and tomato problem may be insect or disease. Hard to determine from blurry photo. Disease problem may be powdery mildew http://edis.ifas.ufl.edu/hs321 if it was insects possibly scale or mealybug.
I suggest you contact the Orange County Extension office http://orange.ifas.ufl.edu/res_hort/index.html#plc to confirm what your problem is and how to deal with it.