Eggplant leaf disease
Never had this disease before, but looks like septoria leaf spot that believe i had on tomatoes previously. Did have some disease that caused all my cucumber plants to die this yr. So far still getting some fruit, but sparse and smaller than usual. Any guess what it is, and any tips for next yr besides removing all debris?
It's difficult to make a definitive diagnosis based on the two photos. Eggplant is susceptible to several fungal leaf spot diseases. The symptoms on your plants are more consistent with injury caused by two sucking insect pests: spider mites and eggplant lace bug. Both feed on leaf undersides. Use a hand lens or magnifying glass to closely examine leaf undersides.
Next year, protect eggplant transplants from the time of planting through the beginning of bloom with a floating row cover. This will prevent flea beetle, spider mite, and lacebug activity. Early season protection is a key to success, along with adequate sunlight, water, spacing, and nutrients.
Spider mites also feed on cucumber but without more information and photos we cannot weigh in on what caused your cucumber plants to go down. jt