Thrips Andor Leaf Miner

Its hard to see enough detail of the damage in this photo, but it could be Thrips insects and we think we see some damage from Leaf Miner insects. There is very little you can do about the leaf miner because they feed (in their larva stage) under the leaf epidermis and pesticidal products are usually not effective as they can’t reach/contact the insect. You can pick off the leaves, but if the larva has already finished eating and pupated into the adult stage (who then flies away), there’s no need to pick off the leaves that can still photosynthesize. Thrips are often the more damaging pest. You can usually use a pesticidal soap or horticultural oil to control them, but we recommend you read the info under the section titled “Chemical Control” on this web-page before using any product. There’s also info about leaf miner in the second link.
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7429.html
http://www.ipm.ucdavis.edu/PMG/GARDEN/VEGES/PESTS/vegleafminers.html