Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae) is an important predatory natural enemy of planthopper and leafhopper eggs in Asian rice paddy fields. Cyrtorhinus lividipennis is known to rely largely on herbivore-induced plant volatiles to identify eggs embedded in rice stem tissues for feeding and on pheromones for mating. However, exactly how C. lividipennis decode these chemical information is unclear. In most insects, the odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) are essential for seeking out food resources and mates. In this study, we identified 10 OBP and 5 CSP genes in C. lividipennis and investigated their expression patterns in various tissues of adult males and females by quantitative real-time PCR (qRT-PCR). Six OBP genes (ClivOBP1, 2, 4, 6, 9, and 10) were mainly expressed in the male antennae, whereas three genes (ClivOBP3, ClivOBP7, and ClivOBP8) had high expression in the female antennae. ClivCSP1 was predominantly expressed in the male antennae. These findings suggest that most ClivOBPs and ClivCSPs are likely involved in food-searching behavior. The recognition of the pheromone molecules provides the basis for further functional studies on the chemoreception system of C. lividipennis.

The rice water weevil, Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), is a serious pest species both in its original distribution region of northern America and its invaded regions of eastern Asia and southern Europe. The odorant-binding proteins (OBPs) and the chemosensory proteins (CSPs) play important roles in host and mate locating, thus might play a significant role in the success of the species as an invader, which has not been characterized yet. We identified 10 OBPs and 5 CSPs in L. oryzophilus and investigated the expression profiles of these genes in various tissues by quantitative real-time PCR. Five classic OBPs were predominantly expressed in the antennae. CSPs were expressed ubiquitously with particularly high transcript levels in antennae, legs, and wings. Three antenna-specific OBPs ( LoOBP1 , 8 , 11 ) were up-regulated following 1–3 d of food deprivation and down-regulated afterward. These findings suggest most classic OBPs are likely involved in chemoreception whereas CSPs as well as the minus-C OBPs may have broader physiological functions, which in turn may help to understand the molecular aspects of chemical communication in this invasive insect.