The Diaprepes root weevil (DRW) is an opportunistic polyphagous weevil with a host range that includes at least 350 different plant hosts (http://edis.ifas.ufl.edu/IN119). The ability to feed on a broad array of plants raises a question on how this insect either avoids, or is immune to, the broad array of plant defenses it encounters. To study this question transcriptome profiling was performed with citrus to identify which plant genes were regulated in response to adult weevil feeding. Comparisons of adult DRW feeding damage to mechanical damage performed to mimic feeding on citrus leaves showed differences in plant responses. In particular, accumulation of plant carbonic anhydrase transcripts occured in response to DRW feeding but not to mechanical damage. Carbonic anhydrase catalyzes the reversible hydration of CO2 to HCO3-. Carbonic anhydrase was shown to be induced in other plants by oxidative stress, and is involved in the plant hypersensitivity response. Our data suggest that DRW feeding may influence the oxidative state of the plant tissue being fed on, and this finding is discussed in relation to avoidance of plant defenses.