Chemoecology (2016) 26, 59-66

Mateus Tonelli, Maria Fernanda Gomes Villalba Peñaflor, Luís Garrigós Leite, Weliton Dias Silva, Fernanda Martins and José Maurício Simões Bento (2016)
Attraction of entomopathogenic nematodes to sugarcane root volatiles under herbivory by a sap-sucking insect
Chemoecology 26 (2), 59-66
Abstract: Few systems have been described in which herbivore-induced root volatiles mediate attraction of entomopathogenic nematodes (EPNs), and they only concern root damage inflicted by chewing insects. EPNs, especially Heterorhabditis indica and Steinernema carpocapsae, are potential biological control agents of sugarcane spittlebug (Mahanarva fimbriolata) populations. Here, we investigated the response of these two species of EPNs to sugarcane root volatiles damaged by M. fimbriolata nymphs in a belowground six-arm olfactometer. We also examined changes on root volatile profile in response to herbivory of sugarcane spittlebug nymphs. Results showed that both EPN species did not discriminate between odors of undamaged sugarcane and moistened sand (blank). However, when EPNs were exposed to odors of spittlebug-damaged and undamaged sugarcane roots, both species significantly preferred odors of spittlebug-damaged roots. Headspace collection followed by GC–MS analyses showed no qualitative difference (total of 11 compounds) between volatile profiles of spittlebug-damaged and undamaged sugarcane roots. In contrast to the previous studies involving feeding by root chewing insects, our root volatile analysis did not reveal any up-regulation resulting from sugarcane spittlebug damage, but the down-regulation of the terpenes dihydromyrcenol and ß-isomethyl ionone when compared with the profile of undamaged sugarcane roots. Here, we propose alternative explanations for the EPN attraction to spittlebug-damaged roots as it is unlikely that reduced concentrations of the volatiles play a role in this interaction. Further studies are necessary to determine the key compounds of the root volatile emission to enhance biological control efficacy with EPNs against M. fimbriolata in sugarcane.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
(original language: English)
Link to article at publishers website
Database assignments for author(s): Luís G. Leite, Maria Fernanda Gomes Villalba Penaflor

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Mahanarva fimbriolata	Sugarcane (Saccharum officinarum)
Steinernema carpocapsae/Xenorhabdus nematophila (entomopathogen)	Mahanarva fimbriolata
Heterorhabditis indica/Photorhabdus (entomopathogen)	Mahanarva fimbriolata