Evaluation of Resistance in seven Apple Cultivars to Rosy Apple Aphid under Greenhouse and Field conditions

Rosy apple aphid, Dysaphis plantaginea (Passerini), with worldwide distribution is an important pest of apple orchards. Host plant resistance is an essential component of integrated management of this insect pest. We investigated the resistance of seven apple cultivars, Malus domestica (Borkhausen), namely Granny Smith, Starkrimson, Golden Smoothee, Red Delicious, Golden Delicious, Boshghabi, and Shaki to rosy apple aphid under field and greenhouse conditions. The damage level by rosy apple aphid was significantly different among the tested cultivars preciously three week after infestation in both field and greenhouse conditions. The least leaf curling was observed on Shaki, while the most deformation was detected on Golden Delicious. There was positive correlation between damage in greenhouse and field studies. In addition, the lowest and highest numbers of aphids were observed on Shaki and Golden Delicious, respectively. Consequently, our results demonstrated that among the cultivars tested the Shaki cultivar is moderately resistant to rosy apple aphid and has the potential to be used in the integrated management of this aphid.