Investigation on resistance of three varieties of roses to the two spotted mite, Tetranychus urticae koch

Two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is an important pest of ornamental plants such as rose plants in many regions of the world. Population densities of this mite were recorded on 3 rose cultivars, including Dolcevita, Red naomi and White naomi in a greenhouse at 20 ± 3°C, 70% RH and 10 hour L and 14 hour D. Numbers of eggs, larvae, nymph and adults were counted in one cm2 on lower part of leaves. Analysis of variances showed that the number of eggs, larvae, nymphs and adults were significantly different on the rose cultivars. The mean number of total mites on Dolcevita, Red naomi and White Naomi were 3.45, 7.7 and 8.97 per square cm. respectively. Based on the results White naomi was the most susceptible and Dolcevita was the least resistant cultivar.