Role of terpenes from aphid‐infested potato on searching and oviposition behavior of Episyrphus balteatus

Abstract

To cope with pathogen and insect attacks, plants develop different mechanisms of defence, in both direct (physical and chemical) and indirect ways (attractive volatiles to entomophagous beneficials). Plants are then able to express traits that facilitate "top-down" control of pests by attracting herbivore predators. Here we investigate the indirect defence mechanism of potato plants by analyzing the volatile patterns of both healthy and aphidinfested plants. Important changes in the emitted terpene pattern by the Myzus persicae infested host plant were observed. Using Solid Phase MicroExtraction (SPME) and GC-MS, the (E)-β-farnesene (EBF) appeared to be emitted by aphid-infested potato and not by healthy plants. To assess the infochemical role of these volatile releases after aphid damage on the aphidophagous predators Episyrphus balteatus, the hoverfly foraging behavior was assessed using the Observer 5.0 software (Noldus, Wageningen, The Netherlands). Aphidfree potato plants were also used as a control volatile source in the predator behavioral study. While aphid-infested plants induced efficient searching and acceptation behaviors leading to egg-laying, no kairomonal effect of healthy potato plants was observed, leading to longer immobility durations and shorter searching periods in the net cage. High oviposition rate of E. balteatus was observed when aphid-infested potato was used (mean of 48.9 eggs per laying and per female). On the other hand, no egg was produced by the hoverfly on healthy aphid-free plants. The E. balteatus foraging and reproductive behaviors according to the volatile emission from aphid-infested plants are discussed in relation to the potential use of active infochemical molecules in integrated aphid pest management.

Tomato-aphid-hoverfly: a tritrophic interaction incompatible for pest management

“…Potatoes have also been presented as suitable host plants for hoverfly female oviposition (e.g. Verma et al 2005;Harmel et al 2007;Almohamad et al 2007). In our behavioral experiments, the negative effect of trichomes on the accessibility of hoverfly adults was visually observed.…”

“…Two additional host plants of Myzus persicae Sulzer (Homoptera, Aphididae), namely broad bean Vicia faba L. 'Grosse ordinaire' (Fabaceae) and potato Solanum tuberosum L. 'Bintje' (Solanaceae), were selected for comparison with the above mentioned tomato cultivars. Vicia faba and S. tuberosum were chosen because they were shown in previous work to be easily exploited as host plants by E. balteatus Harmel et al 2007), and they have different surface proprieties compared to tomato cultivars.…”

“…The oviposition preference of female syrphids has recently been correlated with offspring performance on preferred host plants ). The behavioural impact of various plant and prey secondary metabolites, including volatile and non-volatile chemicals, in the localization and selection of an oviposition site in E. balteatus has largely been demonstrated (Chandler 1968;Kan 1988;Sadeghi and Gilbert 2000a, b;Harmel et al 2007;Almohamad et al 2008b;Verheggen et al 2008). Among these chemicals, the main component of the aphid alarm pheromone, the sesquiterpene (E)-b-farnesene (Francis et al 2005a), acts as an attractant and an oviposition stimulant for various aphid predators including the ladybeetle Harmonia axyridis Pallas and the hoverfly E. balteatus (Almohamad et al , 2008bVerheggen et al 2007Verheggen et al , 2008Verheggen et al , 2009.…”

Fast gas chromatography characterisation of purified semiochemicals from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae)

“…Moreover, β-caryophyllene is a molecule of interest having biological activity against aphid reproduction [2] and was identified as the aggregation pheromone of the Asian lady beetle Harmonia axyridis [8]. One of the main interest of these compounds is that they could act as attractants and oviposition inductors of some aphid predators (Episyrphus balteatus De Geer (Diptera: Syrphidae)) and parasitoids (Aphidius ervi Haliday (Hymenoptera: Braconidae)) [9][10][11][12][13]. The essential oil of Matricaria chamomilla L. (Asteraceae), popularly known as German chamomile (other synonyms: Matricaria recutita L. and Chamomilla recutita L), was reported to contain a high proportion of E-β-farnesene.…”

Tuned protection of aphids by ants against a predatory hoverfly

“…In this guild of aphidophagous insects, the hoverfly Episyrphus balteatus De Geer (Diptera: Syrphidae) is frequently encountered at aphid-infested sites in the temperate regions of the Northern Hemisphere (Schneider, 1969;Gilbert, 236 Claire Detrain, Melanie Fichaux andFrançois Verheggen 1986, 2005;Tenhumberg, 1995). Just like aphid-tending ants, hoverfly females use semiochemicals to locate aphid colonies and to oviposit eggs from which aphidophagous larvae hatch (Harmel et al, 2001;Almohamad et al, 2007;Verheggen et al, 2008;Leroy et al, 2014). Therefore, both actors are likely to encounter each other.…”