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Carpio C., Dangles Olivier, Dupas Stéphane, Léry Xavier, Lopez-Ferber M., Orbe K., Paez D., Rebaudo François, Santillan A., Yangari B., Zeddam Jean-Louis. (2013). Development of a viral biopesticide for the control of the Guatemala potato tuber moth Tecia solanivora. Journal of Invertebrate Pathology, 112 (2), p. 184-191. ISSN 0022-2011.

Titre du document
Development of a viral biopesticide for the control of the Guatemala potato tuber moth Tecia solanivora
Année de publication
2013
Type de document
Article référencé dans le Web of Science WOS:000314381000014
Auteurs
Carpio C., Dangles Olivier, Dupas Stéphane, Léry Xavier, Lopez-Ferber M., Orbe K., Paez D., Rebaudo François, Santillan A., Yangari B., Zeddam Jean-Louis
Source
Journal of Invertebrate Pathology, 2013, 112 (2), p. 184-191 ISSN 0022-2011
The Guatemala potato tuber moth Tecia solanivora (Povolny) (Lep. Gelechiidae) is an invasive species from Mesoamerica that has considerably extended its distribution area in recent decades. While this species is considered to be a major potato pest in Venezuela, Colombia, and Ecuador, currently no specific control methods are available for farmers. To address this issue we developed a biopesticide formulation to be used in integrated pest management of T. solanivora, following three steps. First, search for entomopathogenic viruses were carried out through extensive bioprospections in 12 countries worldwide. As a result, new Phthorimaea operculella granulovirus (PhopGV) isolates were found in T. solanivora and five other gelechid species. Second, twenty PhopGV isolates, including both previously known and newly found isolates, were genetically and/or biologically characterized in order to choose the best candidate for a biopesticide formulation. Sequence data were obtained for the ecdysteroid UDP-glucosyltransferase (egt) gene, a single copy gene known to play a role in pathogenicity. Three different sizes (1086, 1305 and 1353 bp) of egt were found among the virus isolates analyzed. Unexpectedly, no obvious correlation between egt size and pathogenicity was found. Bioassays on T. solanivora neonates showed a maximum of a 14-fold difference in pathogenicity among the eight PhopGV isolates tested. The most pathogenic PhopGV isolate, JLZ9f, had a medium lethal concentration (LC50) of 10 viral occlusion bodies per square mm of consumed tuber skin. Third, we tested biopesticide dust formulations by mixing a dry carrier (calcium carbonate) with different adjuvants (magnesium chloride or an optical brightener or soya lecithin) and different specific amounts of JLZ9f. During laboratory experiments, satisfactory control of the pest (>98% larva mortality compared to untreated control) was achieved with a formulation containing 10 macerated JLZ9f-dead T. solanivora larvae per kg of calcium carbonate mixed with 50 mL/kg of soya lecithin. The final product provides an interesting alternative to chemical pesticides for Andean farmers affected by this potato pest.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Sciences du monde végétal [076] ; Sciences du monde animal [080]
Description Géographique
ANDES
Localisation
Fonds IRD [F B010058973]
Identifiant IRD
fdi:010058973
Contact