Plum Curculio: New Guide Gathers IPM Recommendations for North American Fruit Pest
By Tim Lampasona
The plum curculio (Conotrachelus nenuphar) is an important pest of fruit in North America. Considered oligophagous (feeding only on a limited number of foods), plum curculio largely utilizes rosaceous hosts like stone and pome fruits, but it may be a pest of blueberry in some regions. This insect is endemic to areas east of the Rocky Mountains and has a range from Canada to the southeast, with a univoltine strain in the north and a multivoltine strain in the south. Plum curculio causes three types of damage, including adult feeding and oviposition on the exterior flesh of developing fruit. As the larvae develop and feed internally on the fruit, trees may abort fruit prematurely, leading to a phenomenon known as “June drop.” Larvae then exit the fruit to pupate underground before emerging about a month later to continue the cycle.
As a native species, this insect has a long history in North America, and it has been a thorn in the side of growers for as long as there have been people to grow fruit here. The first writing describing its damage on domesticated fruit dates back to the 18th century, and its propensity for various native fruits indicates that it was almost certainly a pest of indigenous permaculturalists as well.
Despite the long history of this insect as a serious pest in multiple fruit systems, the last truly full review of it was in the seminal 1912 book The Plum Curculio. Subsequent reviews focused on individual or discrete aspects of the plum curculio biology and ecology or its management. Since this first review, there have been advances not only in understanding the biological and behavioral aspects of the species, but also on the development of effective control measures that fit into a modern integrated pest management (IPM) framework.
A new paper, “A Review of the Biology, Ecology, and Management of Plum Curculio (Coleoptera: Curculionidae),” synthesizes the knowledge of this insect into a single review, allowing interested readers to learn the basics about the biology, life history, behavior, and management of the plum curculio in a single piece. The guide—which I co-authored with my Rutgers University colleagues Cesar Rodriguez-Saona, Ph.D., and Anne Nielsen, Ph.D., along with Tracy Leskey, Ph.D., of the U.S. Department of Agriculture-Agricultural Research Service’s Appalachian Fruit Research Station—is published today in the open-access Journal of Integrated Pest Management. Additionally, the historical challenges inherent in managing this pest species are discussed, ranging from early non-chemical methods of control through the era of broad-spectrum calendar-based sprays and up to current IPM tactics. Also discussed are new breakthroughs in monitoring, such as the discovery of the aggregation pheromones and refinement of olfactory lures. An overview of new and promising management techniques is given, including methods such as trap trees/bushes and entomopathogenic nematodes (EPNs) and their implications for IPM moving forward.
Journal of Integrated Pest Management
Tim Lampasona is a Ph.D. student in entomology at Rutgers University. Email: firstname.lastname@example.org.