Answer: Based on your description I am not certain what you are seeing. It is possible it is the egg stage of an insect; these can be picked off by hand and put in the trash.
Or, if you look carefully you might find that a tomato hornworm (a large green caterpillar, blends perfectly with the plant) has been parasitized by a wasp laying eggs on it. They look almost like grains of rice. If this is what happened, leave it in place so you will have more of these great natural garden defenders.
Here is a photo (scroll down the page) and more information about this. You may need to cut and paste the complete url into your browser to make it work correctly.
If it is not one of these, you might want to check with your local county extension and see if they can help you identify it.
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