Occurrence of Two-Spotted Spider Mite (Tetranychus urticae Koch) on Potentilla fruticosa Cultivars

L. (Rosaceae Juss.) is one of the most popular deciduous shrubs cultivated in Poland. Among pests identified so far on , a serious threat is caused by two-spotted spider mite Koch (Acari: Tetranychidae). During three-year study, the occurrence of two-spotted spider mite . on four cultivars of : ‘Goldfinger’, ‘McKay’s White’, ‘Uman’ and ‘Pink Beauty’ grown in field conditions was compared. While conducting experiment, weather conditions were monitored. The number of eggs and motile forms of two-spotted spider mite were recorded separately. The most attractive cultivar to spider mite was ‘Goldfinger’. The largest amount of motile forms of mites and their eggs were found on the leaves of this cultivar in all three years of study. The least number of pests occurred on the cv. ‘Pink Beauty’. However, differences in the abundance of this pest on all studied cultivars were variable during the growing seasons.