Preparation, characterization, and evaluation of PLA/gelatin microspheres containing both insecticide and attractant for control of Rhagoletis batava obseuriosa Kol

Abstract

Sea buckthorn, Hippophae rhamnoides, is a widely distributed tree species that contributes to soil and water conservation. Its fruits, seeds and leaves are also raw materials for many health products. Rhagoletis batava obseuriosa Kol. (RBO) is a fruit fly pest that attacks sea buckthorn berries. Polymeric microspheres have been developed as carriers for pesticides. Here we developed microspheres containing both an insecticide (abamectin) and an attractant (ammonium carbonate) for use in an attract and kill approach for control of RBO. The microspheres obtained were spherical with smooth or poriferous surfaces. The mean particle diameter was 55–78 μm. The release rate could be described by a first-order kinetic equation and the microspheres achieved a good sustained release of both insecticide and attractant. Microspheres were toxic to RBO by contact and following ingestion. Microspheres attracted significantly more RBO to sticky traps than the control. The results showed that the composite microspheres were both toxic due to the abamectin, and attractive due to the ammonium carbonate. These microcapsules have potential to be used in an attract- and-kill control strategy for RBO.