japonica to use photoperiodic volatile emission from F. sachalinensis to response under light conditions. japonica diurnally infests the leaves of F. It is suggested that light is essential for volatile production and/or emission together with activation of the JA signaling pathway.
All of the volatile emission triggered by MeJA was suppressed under constant dark conditions to 29–39% of that under constant light conditions (data not shown). The increase of phenylacetonitrile emission, which initially lagged behind those of terpenes, was time dependent during the experimental period (24 h, Figure 2). The emission of two terpenes increased and reached almost maximum 18 h after MeJA treatment. The emission of the three major volatile components started 3 h after MeJA treatment. Induction of the emission of phenylacetonitrile, ( E)-β-ocimene and ( E, E)-α-farnesene by MeJA was much higher than by insect feeding. Herbivore-induced volatiles were qualitatively mimicked by exogenous airborne MeJA ( Figure 1). This volatile compound may be a potential chemical cue to attract various types of insects, for example, natural enemies, flower-visiting insects, and herbivores. Phenylacetonitrile is also known as one of the floral scent components of Orchidaceae, such as Diaphananthe pellucida and Cactaceae. rapa has been shown to attract parasitoid wasps. Phenylacetonitrile found from caterpillar-infested B. Phenylacetonitrile has been found from insect-infested Manchurian ash, Fraxinus mandshurica and Brassica spp. The above terpenes are well-known volatiles induced by insect feeding, while there are only a few examples in which phenylacetonitrile was found as an herbivore-induced volatile. japonica feeding than undamaged leaves and thus, the herbivore-induced volatiles are likely to serve as host location cues for the beetles. Although it has not been determined whether these terpenes attract beetles, the beetles prefer the leaves of V. sachalinensis is an unique species that emits phenylacetonitrile infested by the same herbivore, P. japonica feeding-induced volatiles from the leaves of grape, Vitis labrusca and crabapple, Malus spp. Caeliferins have been identified as nonlepidopteran elicitors from the American bird grasshopper, Schistocerca americana, which also induce volatiles from plants similar to caterpillar feeding however, there is no example in which the elicitor was identified from Coleoptera and that the elicitor induces nitrile emission from plants.įour terpenes, ( E)-β-ocimene, linalool, DMNT and ( E, E)-α-farnesene, have been found as P. Inseptin is a peptidic elicitor found in oral secretions of lepidopteran larvae, Spodoptera frugiperda, which promote either defense-related phytohormone production or herbivore-induced volatile emission, such as DMNT. Volicitin induces the emission of volatile blends composed of terpenes, green leaf volatiles and indole. It is known that a fatty acid-amino acid conjugate, volicitin, is a strong elicitor that is widely distributed in lepidopteran caterpillars and also found in cricket and fruit fly. These results suggest that volatile emission will be induced by a herbivore-specific factor, an elicitor present in the oral secretion of P. Volatile emission was not observed from either undamaged leaves or mechanically damaged leaves. japonica feeding were analyzed by GC–MS and the volatile components were identified as phenylacetonitrile, ( E)-β-ocimene, linalool, DMNT and ( E, E)-α-farnesene, as shown in Figure 1 and Table 1. sachalinensis is also induced by treatment with exogenous airborne MeJA. japonica and that an uncommon type of herbivore-induced volatile, phenylacetonitrile (benzyl cyanide), from F. Here we report the identification of volatiles from the leaves of F. In this context, we speculate that the odor will function for beetle attraction, and plan to investigate the volatile composition. The same grape-like odor is reproduced under laboratory conditions where the beetles are fed on F. During our field research around Akita City in Japan, the beetles are often found on the leaves of the giant knotweed, Fallopia sachalinensis (Polygonaceae), and infested plants in the field smell like sweet grapes (our personal observation). Both female and male beetles are attracted by floral or fruit-like odors, such as geraniol, eugenol and phenethyl propionate, which enhance the attraction of males when treated with a sex pheromone, japonilure. The Japanese beetle, Popillia japonica (Coleoptera: Scarabaeidae), is known to be a destructive pest in North America that damages leaves, flowers or fruits of more than 300 plant species.
0 kommentar(er)
