One of my favorite veggies is eggplant...it took me a while to learn to cook it right and now we love it.
We have had problems with caterpillars on our eggplant. I now use dry cayenne pepper. We crush this with a roller making sure it is very fine almost like dust. I sprinkle the cayenne on the eggplant while there is still dew on the plants.
If you grow eggplant among your green beans this will protect your plants from the Colorado potato beetle. The beetles like eggplant even more than your potatoes but they will find the green beans as a repellent.