| Title: | Optimisation of a semiochemical slow-release alginate formulation attractive towards Aphidius ervi Haliday parasitoids |
| Author(s): | Heuskin S; Lorge S; Godin B; Leroy P; Frere I; Verheggen FJ; Haubruge E; Wathelet JP; Mestdagh M; Hance T; Lognay G; |
| Address: | "Department of Analytical Chemistry, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium" |
| ISSN/ISBN: | 1526-4998 (Electronic) 1526-498X (Linking) |
| Abstract: | "BACKGROUND: Optimisation of alginate formulations is described in order to develop semiochemical (E-beta-farnesene and E-beta-caryophyllene) slow-release devices in biological control approaches by attracting predators and parasitoids of aphids. Various formulation criteria were optimised with respect to semiochemical encapsulation capacity. Moreover, the optimised formulation was characterised by texturometry and confocal microscopy. The slow-release rates of semiochemicals were calculated in laboratory controlled conditions. The attractiveness of semiochemical formulations towards Aphidius ervi was demonstrated by olfactometry. RESULTS: Two major parameters were highlighted in encapsulation optimisation: the type of alginate (Sigma L) and the type of crosslinker ion (Ca(2+)). Other formulation parameters were optimised: ionic strength (0.5 M), Ca(2+) (0.2 M) and alginate (1.5%) concentrations and the maturation time of beads in CaCl(2) solution (48 h). After physical characterisation of beads, semiochemical slow-release measurements showed that alginate formulations were efficient sesquiterpene releasers, with 503 microg of E-beta-farnesene and 1791 microg of E-beta-caryophyllene totally released in 35 days. The efficiency of semiochemical alginate beads as attractants for female parasitoids was demonstrated, with high percentages of attraction for semiochemical odours (88 and 90% for E-beta-farnesene and E-beta-caryophyllene respectively) and significant statistical results. CONCLUSION: Semiochemical alginate beads can be considered as efficient slow-release systems in biological control. These formulations could be very useful to attract aphid parasitoids on crop fields" |
| Keywords: | "Alginates/*chemistry Animals Aphids/*drug effects/physiology Chemistry, Pharmaceutical/*methods Delayed-Action Preparations/chemistry/*pharmacology Female Glucuronic Acid/chemistry Hexuronic Acids/chemistry Pest Control, Biological Pheromones/chemistry/*p;" |
| Notes: | "MedlineHeuskin, Stephanie Lorge, Stephanie Godin, Bruno Leroy, Pascal Frere, Isabelle Verheggen, Francois J Haubruge, Eric Wathelet, Jean-Paul Mestdagh, Michele Hance, Thierry Lognay, Georges eng Evaluation Study Research Support, Non-U.S. Gov't England 2011/07/05 Pest Manag Sci. 2012 Jan; 68(1):127-36. doi: 10.1002/ps.2234. Epub 2011 Jul 1" |
