BACKGROUND Stegobium paniceum (Coleoptera, Anobiidae) is an important pest of stored products causing severe damage to dried Chinese medicinal plant materials (CMPMs). Plant volatiles play an important role in host‐searching of insects. The olfactory responses of S. paniceum to the most abundant volatile components of some drugstore attractant CMPMs such as Panax notoginseng, Angelica sinensis, Gastrodia elata and Peucedanum praeruptorum, namely falcarinol, 3‐n‐butylphthalide, p‐cresol and β‐pinene, respectively, were studied by electroantennography (EAG) and behavioural bioassays in six‐ and four‐arm olfactometers. RESULTS EAG recordings showed that male and female antennae are able to perceive the test compounds in a wide range of concentrations and in a dose‐dependent manner. Moreover, for each dose of different compounds tested, no significant differences were found between the mean male and female EAG responses. In six‐arm olfactometer bioassays, S. paniceum exhibited positive responses to falcarinol, 3‐n‐butylphthalide, p‐cresol and β‐pinene at doses of 1, 10, 100, 500 and 1000 μg. The most attractive dose was 500 μg for falcarinol, 100 μg for 3‐n‐butylphthalide, 500 μg for p‐cresol and 1000 μg for β‐pinene. Olfactory preferences of S. paniceum, based on comparison of these four compounds at their optimally attractive concentrations in a four‐arm olfactometer, were 3‐n‐butylphthalide > p‐cresol > falcarinol > β‐pinene. CONCLUSION The results indicated that the four volatiles of CMPMs are perceived by the peripheral olfactory system of S. paniceum adults and are able to individually elicit a positive chemotaxis in S. paniceum adults confirming the role of chemical cues in host‐plant detection and selection of this pest. Further field studies are needed to evaluate the potential of the attractive compounds identified in this study, particularly 3‐n‐butylphthalide, to be applied as a novel monitoring and control tool against this storage‐beetle pest. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

In order to explore the influence of stored cereal volatiles on the behavior of Sitophilus oryzae, the olfactory responses of adult rice weevils to the volatiles of different rice cultivars [Red brown rice (RBR), Daohuaxiangmi (DHXM), Baishuigongmi (BSGM), Yashuixinmi (YSXM), and white glutinous rice (WGR)] were studied using electroantennography (EAG) and behavioural bioassays in different types of olfactometers. S. oryzae showed significantly different preferences for these rice cultivars, in the order RBR > DHXM = YSXM ≥ BSGM > WGR. Furthermore, 26 components were identified in the volatile profile of RBR. Nonanal (29.37%), hexanal (16.08%), and 1-octen-3-ol (8.83%) were the most abundant compounds. EAG recordings showed that the antennae of S. oryzae were able to perceive these three compounds in a dose-dependent manner. The compounds elicited significant EAG responses at various concentrations, with the strongest responses at 100 μg μL−1. S. oryzae had a significant positive behavioural response to nonanal, hexanal, and 1-octen-3-ol at various concentrations, with the most attractive being 50, 100, and 100 µg µL−1, respectively. The olfactory preferences of S. oryzae, based on a comparison of these compounds at their optimal concentrations, were nonanal > 1-octen-3-ol = hexanal. These results indicated that the volatiles of the preferred rice cultivar (RBR) were perceived by the peripheral olfactory system of S. oryzae adults and individually elicited positive chemotaxis. These findings offer new insights into the mechanism of host preferences of stored-grain pests. Nonanal showed the greatest potential for use as a novel monitoring and control tool against this storage-beetle pest.