A food supplement for the predatory mite Iphiseius degenerans (Berlese) in sweet pepper crops

Abstract: Until recently, the preventative use of the predatory mite Iphiseius degenerans was only possible in crops producing an abundant amount of pollen. This changed since the commercial introduction of pollen food supplements (NutrimiteTM) allowing establishment of predatory mites in the absence of prey or flowers. In this study, we evaluated the potential of using I. degenerans in combination with pollen supplements, to preventatively control Frankliniella occidentalis and Bemisia tabaci on non-blooming sweet peppers in cage trials and compared it to the performance of Amblyseius swirskii. Iphiseius degenerans was shown to develop larger populations than A. swirskii, resulting in better control of F. occidentalis and B. tabaci. Interestingly, application of pollen also enhanced the predator’s population levels during the full blooming period of the crop, indicating that NutrimiteTM provides nutritional benefits over sweet pepper pollen. In a commercial sweet pepper crop, the use of NutrimiteTM allowed growers to introduce and establish I. degenerans earlier in the season. Nowadays, the predatory mite is commonly introduced in combination with the food supplement about eight weeks earlier than in conventional cultivation. Early introductions of I. degenerans with pollen were also implemented at propagators in 2015.