Olfactory Responses to Aphid and Host Plant Volatile Releases: (E)-β-Farnesene an Effective Kairomone for the Predator Adalia bipunctata (original) (raw)
Related papers
Journal of Chemical Ecology, 2000
The volatiles released from several aphid and host plant species, alone or associated, were studied for their infochemical role in prey location. Using a four-arm olfactometer, the attraction of several combinations of three aphid (Myzus persicae, Acyrthosiphon pisum, and Brevicoryne brassicae) and three plant (Vicia faba, Brassica napus, and Sinapis alba) species toward Adalia bipunctata larvae and adults was observed. Both predatory larvae and adults were attracted only by A. pisum and M. persicae when they were crushed, whatever the host plant. (E)-β-Farnesene, the aphid alarm pheromone, was the effective kairomone for the ladybird. Plant leaves alone (V. faba, B. napus, and S. alba) or in association with nonstressed whole aphids (the three species) did not have any attraction for the predator. The B. brassicae specialist aphid is the only prey that was not attracted to A. bipunctata larvae and adults, even if they were crushed. Release of B. brassicae molecules similar to the host plant allelochemicals was demonstrated by GC-MS analysis. The lack of behavioral response of the ladybird at short distance toward the cruciferous specialist aphid was related only to the absence of (E)-β-farnesene in the aphid prey volatile pattern.
The Influence of Aphid-Induced Plant Volatiles on Ladybird Beetle Searching Behavior
Biological Control, 2001
Field-collected individuals of the seven-spotted ladybird, Coccinella septempunctata L. (Coleoptera, Coccinellidae), were tested for response to volatiles from aphids (Rhopalosiphum padi (L.)), from aphid-infested barley plants (Hordeum vulgare), and from previously aphid-infested and uninfested plants. The volatiles were collected by conventional polymer entrainment techniques, and diethyl ether eluates of the entrainments were used as odor sources in olfactometer bioassays. C. septempunctata responded positively to volatiles from aphid-infested plants and from previously aphid-infested plants but not to volatiles from uninfested plants or from undisturbed aphids. The ecological implications of the findings are discussed.
Attraction of two lacewing species to volatiles produced by host plants and aphid prey
Naturwissenschaften, 2005
It is well documented that host-related odors enable many species of parasitoids and predatory insects to locate their prey and prey habitats. This study reports the first characterization of prey and prey host odor reception in two species of lacewings, Chrysoperla carnea (Say) and Chrysopa oculata L. 2-Phenylethanol, one of the volatiles emitted from their prey's host plants (alfalfa and corn) evoked a significant EAG response from antennae of C. carnea. Traps baited with this compound attracted high numbers of adult C. carnea, which were predominantly females. One of the sex pheromone components (1R,4aS,7S,7aR)-nepetalactol of an aphid species, Acyrthosiphon pisum (Harris) attracted only C. oculata adults. Single sensillum recordings showed that the olfactory neurons of C. carnea responded to both 2-phenylethanol and aphid sex pheromone components, but those of C. oculata only responded to the latter.
Phytoparasitica, 2009
The spider mites Tetranychus urticae Koch and Panonychus ulmi (Koch) (Tetranychidae) cause severe economic losses to vegetable farms and deciduous fruit orchards in Turkey. One of their predators, the ladybird beetle Stethorus gilvifrons (Muls.) (Col., Coccinellidae), aggregates on miteinfested patches of plants. The present study assessed whether there is a role for herbivore-induced plant volatiles (HIPVs) and/or odors emitted directly from these two mite species in the aggregative response of ladybird beetles. The olfactory responses of the predator females to volatiles from T. urticae-and/or P. ulmi-infested sweet pepper (four cultivars, viz. 'Demre', 'Yalova Carliston', 'Kandil Dolma' and 'Yag Biberi'), kidney bean (cv. 'Barbunya') and apple (M9 rootstock) were investigated using a two-choice olfactometer. Our results showed that HIPVs emitted from both T. urticae-and P. ulmi-infested plants significantly attracted S. gilvifrons adults for all plants except the sweet pepper cv. Yag Biberi. In addition, it was found that volatiles from apple plants infested by T. urticae and, especially, P. ulmi are more attractive for S. gilvifrons females than those emitted by other infested plants. The results also suggest that the odors of T. urticae adults and their products might influence the attraction of S. gilvifrons females.
Bulletin of Entomological Research, 2009
All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to females. While some host-plant odours are known to enhance specific attraction of aphid species, herbivore-induced plant volatiles that synergise attractiveness to the sex pheromone are unknown. Here, we demonstrate that for the host-alternating rosy apple aphid (Dysaphis plantaginea (Passerini)) specificity of attraction of males to females is triggered by female-induced tree odours in combination with a 1 : 8 ratio of (4aS,7S,7aR)-nepetalactone and (1R,4aS,7S,7aR)-nepetalactol. Female aphid infestation induces increased release of four esters (hexyl butyrate, (E)-2-hexenyl butyrate, (Z)-3-hexenyl 3-methylbutyrate and hexyl 2-methylbutyrate) from apple leaves. Two different combinations of three esters applied in a 1 : 1 : 1 ratio increase the number of male D. plantaginea and decrease the number of other aphid species caught in water traps in the presence of the pheromone components. The ester blend alone was not attractive. Combination of the pheromone blend with each single ester was not increasing attraction of male D. plantaginea. The demonstration that sexual aphid species use herbivore-induced plant volatiles as a species-specific attractant for mate finding adds a new dimension to our understanding of insect species using or manipulating chemical cues of host plants for orientation.
… Experimentalis et Applicata, 2010
Based on their effect on prey populations, predators can interact synergistically, additively, or antagonistically. Predator attraction by semiochemicals in response to herbivory is well documented; however, the possibility of semiochemicals mediating synergistic interactions has not been explored. Eriopis connexa (Germar) and Hippodamia variegata (Goeze) (both Coleoptera: Coccinellidae) interact synergistically with carabid species in Central Chile, a phenomenon in which semiochemicals may be involved. Moreover, olfactory behaviour in these coccinellids is unknown. Olfactometries contrasting non-infested vs. infested plants with Acyrthosiphon pisum Harris (Hemiptera: Aphididae) were performed to study olfactory prey-searching in E. connexa, H. variegata, and Trirammatus striatula (Fabricius) (Coleoptera: Carabidae). To evaluate whether semiochemicals can mediate synergistic predatory interactions, four experiments were established: olfactometries contrasting (1) infested plants with and without a predator, (2) uninfested plants with and without a predator; (3) predator vs. air, and (4) plants with previous physical activity of a predator vs. clean plants (nine combinations of predator species, according to whether they corresponded to the stimulus or focal individual). Hippodamia variegata and T. striatula were attracted to infested plants when contrasted with noninfested plants. Infested plants with a conspecific and H. variegata elicited attraction in E. connexa, whereas T. striatula preferred infested plants with E. connexa or H. variegata. Treatments with only predators (with or without the plant) did not elicit responses, except in E. connexa which was repelled by conspecifics and H. variegata, perhaps indicating an antagonistic interaction between them; plants with previous physical activity of predators did not elicit responses. These results corroborated the importance of semiochemicals produced by herbivory in the prey-searching behaviour of aphidophagous predators. In addition, presence of predators on the foliage may favour emission of aphid alarm pheromones, which could attract E. connexa and T. striatula. Volatiles can intervene in synergistic interactions between carabids and coccinellids; this should be replicable in other systems where predator-facilitation between aphidophagous predators is observed.
Insect Science, 2019
The ladybird beetle Coccinella septempunctata (L.) is an important biocontrol agent of pests such as various aphid species. Despite being one of the most studied coccinellid species, many aspects of its foraging behavior are still not completely understood. This study focuses on the diel foraging behavior of C. septempunctata, investigating their olfactory orientation toward aphid-infested plants, walking activity on plants and on the soil, and feeding rates. In the scotophase the ladybird beetles were significantly more attracted to the odor of aphid-infested plants, on which they also showed considerably higher walking activity then on uninfested controls. Females were more prone to utilize olfactory cues when searching for prey and fed at higher rates than males; this shows that they are better adapted to nocturnal activity, as they require higher food intake. Coccinella septempunctata have the same feeding rate during the scotophase as in the photophase. Our study shows that C. septempunctata has the potential to forage in the scotophase if prey is abundant. The results support the hypothesis that volatiles of aphid-infested plants can attract or arrest foraging adult ladybird beetles, even in the darkness, which makes a considerable contribution to efficient prey search and enhances feeding capacity.
Herbivore-induced plant volatiles provide foraging cues for herbivores and for herbivores' natural enemies. Aphids induce plant volatile emissions and also utilize plant-derived olfactory volatile cues, but the chemical ecology of aphids and other phloem-feeding insects is less extensively documented than that of chewing insects. Here, we characterize the volatile cues emitted by turnip plants (Brassica rapa) under attack by an aphid (Myzus persicae) or by the chewing lepidopteran larva Heliothis virescens. We also tested the behavioral responses of M. persicae individuals to the odors of undamaged and herbivore-damaged plants presented singly or in combination, as well as to the odor of crushed conspecifics (simulating predation). Gas chromatographic analysis of the volatile blend of infested turnips revealed distinct profiles for both aphid-and caterpillar-induced plants, with induced compounds including green-leaf alcohols, esters, and isothiocyanates. In behavioral trials, aphids exhibited increased activity in the presence of plant odors and positive attraction to undamaged turnip plants. However, aphids exhibited a strong preference for the odors of healthy versus plants subjected to herbivore damage, and neither aphid-or caterpillar-damaged plants were attractive compared to clean-air controls. Reduced aphid attraction to herbivore-infested plants may be mediated by changes in the volatile blend constituent composition, including large amounts of isothiocyanates and green-leaf volatiles or, in the case of aphid-infested plants, of the aphid alarm pheromone, (E)-b-farnesene.
Host-locating response by the aphid parasitoid Aphidius ervi to tomato plant volatiles
Journal of Plant Interactions, 2007
The blend of volatile compounds emitted by tomato plants (Solanum lycopersicum) infested with the potato aphid (Macrosiphum euphorbiae) has been studied comparatively with undamaged plants and aphids themselves. Aphid-infested plants were significantly more attractive towards Aphidius ervi than undamaged plants and aphids themselves. Oriented response towards host-damaged plant, from which aphids were removed just before running the bioassay, did not differ from that recorded for infested plants. Collection of the volatiles and analysis by gas chromatography revealed only quantitative differences between uninfested and aphid-infested plants. Nine compounds, a-pinene, (Z)-3-hexen-1-ol, a-phellandrene, limonene, (E)-b-ocimene, p-cymene, methyl salicylate, (E)-b-caryophyllene and an unknown compound, were emitted at higher levels from aphid-infested plants than from undamaged control plants, whilst no differences were noted for hexanal, 6-methyl-5-hepten-2-one, and humulene (0a-caryophyllene). Synthetic standards of these compounds were tested in wind tunnel bioassays and all elicited a significant increase in oriented flight and landings on the target by the aphid parasitoid Aphidius ervi. (E)-b-caryophyllene resulted the most attractive towards female wasps. These results corroborate the hypothesis that the volatiles produced by the plant in response to aphid attack derive from both jasmonic and salicylic acid pathways, and are exploited by A. ervi as olfactory cues to locate its hosts.
Emission of alarm pheromone by non-preyed aphid colonies
Journal of Applied Entomology, 2008
The sesquiterpene (E)-β-farnesene (Eβf) is the primary component of the alarm 9 pheromone of most aphid species. It is released in response to physical stress including attack 10 by natural enemies and causes aphids to cease feeding and disperse. Eβf also acts as a 11 kairomonal cue for aphid natural enemies. In the present study, we collected the headspace 12 volatiles released by aphid colonies of different sizes. GC-MS analysis demonstrated the 13 presence of Eβf in absence of predator attack. A quadratic relationship was found between the 14 released (E)-β-farnesene amounts and aphid colony size. Behavioural impact of aphid alarm 15 pheromone toward E. balteatus female oviposition behaviour was also demonstrated in this 16 work. These results highlight the primary role of the small but continuous release of aphid 17 alarm pheromone in mechanisms of decision-making by aphid predators during their foraging 18 and egg-laying behaviour. 19 20