Laboratory and field studies to assess the efficacy of the predatory mite Typhlodromus (Anthoseius) recki (Acari: Phytoseiidae) introduced via banker plants to control the mite pest Aculops lycopersici (Acari: Eriophyidae) on tomato

The predatory mites (Phytoseiidae) tested to date cannot effectively control the mite pest Aculops lycopersici (Acari: Eriophyidae) due to the unfavorable characteristics of tomato leaves and stems. However, recent studies show that the phytoseiid, Typhlodromus (Anthoseius) recki, can feed on this pest. Because T. (A.) recki is naturally present in high densities on Mentha suaveolens and Phlomis fruticosa, we performed preliminary studies using these species as banker plants in laboratory and greenhouse conditions. In laboratory conditions, we analyzed the effect of banker plants inoculated with T. (A.) recki and co-planted with tomato plants (infested or not with A. lycopersici) at two banker to tomato plants ratios. T. (A.) recki dispersed and established on tomato plants. Higher predator densities were observed on infested plants when M. suaveolens was used as a banker plant with a ratio of one banker plant to two tomato plants. In greenhouse conditions, predators were introduced on tomato plants (infested with A. lycopersici) via branches of banker plants at two densities. T. (A.) recki significantly reduced the length and intensity of stem russeting and A. lycopersici densities. The number of T. (A.) recki on tomato plants was the highest using branches of M. suaveolens at the higher densities released. These results underscore the efficacy of T. (A.) recki in controlling A. lycopersici and open new avenues for the use of M. suaveolens as a reservoir of this predator.