Influence of leaf pubescence on the behavior of the two-spotted spider mite (Tetranychus urticae) and the European red mite (Panonychus ulmi)

Movement behavior of two mite species: two-spotted spider mite (Tetranychus urticae) and European red mite (Panonychus ulmi) on leaves of some apple cultivars (´Greensleeves´, ´Spartan' and SA 455-2 selection) with different density of pubescence was analysed. Assessment of the leaf pubescence density was performed using an originally developed quick method based on digital pubescence mage analysis. For P.ulmi, both stop time and average speed did not depend on kind of leaf. In contrary. T.urticae revealed higher movement activity on slight pubescent leaves compared to leaves with high leaf hair density.