Historical document
Understanding the fundamental interactions between woolly apple aphid and pome fruit (AP06011)
Publication date: December 1, 2009
Delivery Partner: Victorian Department of Primary Industries (VICDPI)
This is a final research report from Hort Innovation’s historical archives. Please note that as these reports may date back as far as the 1990s, the content and recommendations within them may be superseded by more recent research.
Victoria produces more than 25 per cent of Australia’s apple production. A major economic cost to apple growers was the use of insecticides to control pests. The woolly apple aphid (WAA) was a serious pest of apples in Australia and over the previous ten years reports of its incidence had increased. It induced galls on foliage and underground parts of apple trees and also produced honeydew, which on the leaves and fruit forms a reservoir for sooty mould, reducing fruit quality and marketability and photosynthetic efficiency. Severe infestations on young trees caused stunting or even death. Woolly apple aphid was becoming a major problem for apple growers at the time, who were attempting to follow world best practice by adopting intensive production systems and reducing broad-spectrum pesticide usage. Over recent years, partly due to a reduction in use of pesticides, but also because of the use of susceptible rootstocks (including seedling stocks in ‘conventional’ plantings), WAA incidence had increased. Many growers were now routinely treating trees with chemicals to control woolly apple aphid. While this was effective on young trees, reliance on a single chemical group was unsustainable and would ultimately lead to WAA resistance to some pesticides.
The research team utilised their expertise in insect physiology, electrophysiology and applied entomology to develop a better understanding of the feeding interactions between the pest and its host-plant that and further research development this would lead to improved management of woolly apple aphid.
Developments within this project have included:
This historical project was a strategic levy investment in the Hort Innovation Apple and Pear Fund
© 2026 Horticulture Innovation Australia Limited.
Related industries
