Attraction of Sitophilus oryzae (L.) (Coleoptera: Curculionidae) to the semiochemical volatiles of stored rice materials

Abstract

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.

Electrophysiological and Behavioral Responses of Plodia interpunctella (Hübner) Females to Aldehyde Volatiles from Dried Fruits

“…45 Cao et al reported that red brown rice volatiles hexanal and nonanal elicited significant EAG and behavioral responses at various concentrations to Sitophilus oryzae (Coleoptera: Curculionidae). 46 Ukeh et al showed that a synthetic blend of hexanal, octanal, and (E)-2-heptanal identified from maize seed volatiles was significantly attractive to Sitophilus zeamais (Coleoptera: Curculionidae). 47 Similar studies have been reported on various insect species, for example, Triatoma infestans (Hemiptera: Reduviidae), Dinoderus minutus (Coleoptera: Bostrichidae), and Apis cerana (Hymenoptera: Apidae).…”

“…Heptanal, octanal, and nonanal are the main chemical component of cereal volatiles . Cao et al reported that red brown rice volatiles hexanal and nonanal elicited significant EAG and behavioral responses at various concentrations to Sitophilus oryzae (Coleoptera: Curculionidae) . Ukeh et al showed that a synthetic blend of hexanal, octanal, and (E)-2-heptanal identified from maize seed volatiles was significantly attractive to Sitophilus zeamais (Coleoptera: Curculionidae) .…”

Acceptance and utilization efficiency of a purple durum wheat genotype by Sitophilus granarius (L.)

“…Thus, sustainable control means as alternatives to chemical inputs during cereal storage are urgently needed 13 , 15 . Possible alternative control methods include the use of botanicals powders, extracts, and essential oils (EOs) of plant origin 13 , 16 – 23 , semiochemicals 12 , 14 , 24 , inert powder 25 – 31 and resistant varieties 32 .…”