Comparative suitability of different nutrients for feeding the predaceous mite, Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae), in the laboratory

Abstract

Abstract Background The attractiveness, the stickiness and the edibility span of 29 nutrients were assessed to reveal the comparative suitability of each nutrient for feeding the predaceous mite Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). Results Baker's yeast generally was the most attractive-food source. The mixture of skim milk, honey, yolk, baker's yeast and amino acid solution 10% at a volume ratio of 100:1:1:20:1, respectively, was the most attractive mixture. No mite individual fed on honey, the three nutrients containing amino acid solution at high concentrations, chicken blood, smashed cow liver, living drosophila stages, or cotton pollen. Over two minutes, no mite individual stuck to honey, baker's yeast, the three nutrients containing amino acid solution at high concentrations, chicken blood, smashed cow liver, or drosophila types. On the contrary, all the mite individuals exposed to cotton pollen stuck to it on touching. Grape juice was the most adhesive of the rest of the nutrients. The mixture of skim milk, honey, yolk, baker's yeast, and amino acid solution 10% at the volume ratio of 100: 20: 1: 1: 1, respectively, was the most adhesive mixture. The mixture containing the same components at a volume ratio of 100: 1: 20: 1: 1, respectively, was the least adhesive mixture. By examining each of the 19 edible nutrients individually, water was found to be edible until evaporation. Amongst the rest of the edible nutrients, maize pollen had the longest edibility span; it continued valid for feeding for about four days. On the contrary, the yolk continued to be edible for just seven minutes. As regards the edible mixtures, the mixture containing skim milk, honey, yolk, baker's yeast and amino acid solution 10% at a volume ratio of 100:20:1:1:1, respectively, had the longest edibility span. On the contrary, the mixture containing the same components at a volume ratio of 100:1:20:1:1, respectively, had the shortest edibility span. As regards the components of the edible mixtures, honey percentage showed a negative correlation with the number of the attracted mites, whereas it showed positive correlations with each of the number of the stuck mites and edibility span. Compared with honey, yolk and baker's yeast showed opposite trends. Conclusions Each of the examined edibles had its good points as a food for A. swirskii.