Submitted to: HortScience
Publication Type: Peer reviewed journal
Publication Acceptance Date: 7/8/2005
Publication Date: 12/1/2005
Citation: Hogmire, H.W., Miller, S.S. 2005. Relative susceptibility of new apple cultivars to arthropod pests. HortScience. 40(7): 2071-2075. Interpretive Summary: The objective and systematic evaluation of apple cultivars across many planting sites in North America would provide valuable assistance to growers in selecting new cultivars to plant. Insect pest susceptibility is a very important attribute that growers use in selecting new cultivars to plant. Cultivars with high insect pest resistance are more attractive to growers because they require fewer costly pesticide sprays to produce high quality fruit. A reduction in pesticide use is also an expressed desire by the general public A regional project was initiated in 1995 to evaluate apple cultivars on Malling 9 dwarfing rootstock planted at 19 sites across North America. The present paper examines the arthropod insect susceptibility of these newer apple cultivars when grown in the commercial growing region of West Virginia. The ‘Golden Delicious’ apple cultivar served as a standard of comparison for evaluating the insect pest susceptibility of apple cultivars in this study. Results of this study will provide valuable information to extension fruit specialists and apple growers in the mid-Atlantic area and throughout the eastern apple growing regions of the United States.
Technical Abstract: As part of a regional NE-183 project (Multidisciplinary Evaluation of New Apple Cultivars), 23 apple (Malus x domestica Borkh.) cultivars were evaluated for arthropod pest susceptibility. Incidence or injury data were collected from six foliage and eight fruit pests under field conditions over a four year period (2000-2003). Cultivars were ranked based on susceptibility (least to most) to each pest, and rankings were summed for members of the foliage and fruit pest group to develop a susceptibility rating for foliage, fruit and all pests combined. Cultivars with lowest susceptibility to foliage pests included ‘GoldRush’ and ‘Pioneer Mac’, whereas ‘Yataka’ and ‘Cameo’ were most susceptible. For fruit pests, susceptibility was lowest for ‘Pristine’ and ‘Sunrise’, and highest for ‘Cameo’, ‘Fuji Red Sport #2’, and ‘Gala Supreme’. When both foliage and fruit pests were combined, susceptibility was lowest for ‘Sunrise’ and ‘Pioneer Mac’, and highest for ‘Cameo’. Some increasingly popular cultivars had high levels of injury from a few pests, including plum curculio and apple maggot on ‘Ginger Gold’, codling moth and oriental fruit moth on ‘Cameo’, and Japanese beetle, plum curculio and apple maggot on ‘Honeycrisp’. A positive correlation was found between day of harvest and percent fruit injury from codling moth/oriental fruit moth and tufted apple bud moth/redbanded leafroller, with later maturing cultivars experiencing higher injury levels due to more exposure to later generations of these pests. Differences among cultivars in pest incidence and injury can be used by growers to improve pest management through cultivar selection, or by making modifications in control programs based on cultivar susceptibility.