Evaluation of Biological Efficacy of Phytoseiulus persimilis Athias-Henriot and Transeius montdorensis (Schicha) (Acari, Phytoseiidae) against the Red Spider Mite Tetranychus urticae Koch (Acari, Tetranychidae) on Roses in the Laboratory

The efficacy of two predatory phytoseiid mite species, Phytoseiulus persimilis and Transeius montdorensis , against the spider mite Tetranychus urticae on rose plants of Kordana variety was evaluated in the laboratory. All variants of the experiment were carried out in triplicate over 14 days, at a temperature of +25°C and relative air humidity of 70–75%. At the end of the experiment with Ph. persimilis , the density of T. urticae decreased from 20.8 ± 0.9 to 0.9 ± 0.5 ind. per model leaf; the biological efficacy of the predator was 95.7%. In the variant with T. montdorensis , the density of T. urticae decreased from 20.1 ± 1.0 to 8.7 ± 1.1 ind. per leaf, and the biological efficacy did not exceed 63.0%. In the variant without predatory mites, the density of T. urticae increased by the end of the experiment from 22.4 ± 1.0 to 65.6 ± 1.5 ind. per leaf. A single release of Ph. persimilis at a predator : prey ratio of 1 : 10 was effective, but a single release of T. montdorensis failed to produce the expected result. Therefore, the latter species can only be used as an additional predator when other entomoacariphages are present in the greenhouse.