Focus on Popillia japonica

Since the introduction of the Japanese beetle, Popillia japonica (Coleoptera: Scarabaeidae), to the United States in 1916, the pest has had a long history of range expansion, and is now established in at least 28 states. In 2014, P. japonica was found for the first time in continental Europe, with detections in northern Italy, and subsequently southern Switzerland. Most recently, a population was confirmed near Vancouver, British Columbia, Canada. Adult beetles are quite opportunistic and readily colonize and damage over 300 host plant species, ranging from field crops (maize, soybean), to horticultural crops (wine grapes, raspberry, apple), and ornamentals such as linden trees. The larval (grub) stage actively feeds on root tissue of several turf species, utilizing turf on golf courses, residential lawns, perennial meadows, and potentially turf growing within the trellis rows of vineyards and orchards. Thus, urban as well as agricultural regions can harbor infestations, facilitate spread, and thus trigger substantial insecticidal sprays to suppress populations. Because of the damage potential, the beetle has been designated a quarantine pest in some regions (e.g., California-U.S., and EU countries). In response to the risk to plant health in Europe, a collaborative international research group IPM Popillia was created with the aim to coordinate and facilitate research activities among multiple countries. Leaders from this group and the U.S. will serve as Guest Editors to encourage timely publication of research to accelerate our understanding of P. japonica biology and management.

One of the challenges to effective management of P. japonica is that few – if any - soil-applied or foliar insecticides, labeled for larval and adult stages, respectively, are approved for use in some countries or are currently being reviewed by regulatory agencies. This is particularly true in several EU countries. As this pest continues to expand its range, it is imperative to investigate alternatives to chemical control. Moreover, an improved understanding of P. japonica biology, behavior, and ecology is necessary to develop a solid foundation for future pest management programs. We believe this Research Topic will prove to be a valuable venue for publishing novel research on a variety of P. japonica research priorities in the near future. We look forward to new submissions in the topic areas highlighted below.

Article types:

This Research Topic welcomes several types of articles, including: original research, opinion, perspective, mini-review and review articles, that examine all aspects of P. japonica invasion ecology and management. Potential contributions include, but are not limited to:
• Early detection, monitoring and spread rates of P. japonica larval, adult populations
• Invasion biology and population ecology
• Dispersal of P. japonica (human-aided, or natural) and pathways of pest introduction
• Range expansion within the context of global climate change
• Behavioral studies, chemical ecology of insect-plant interactions
• Larval/adult feeding injury, measuring the impact on high-value crops
• Novel integrated pest management (IPM) solutions with low environmental impact
• Natural antagonists and biological control agents, and trophic interactions
• Synergies between biological control and pest-resistant varieties
• Novel genetic/genomics studies on P. japonica, or bacteria, entomopathogenic fungi, nematodes and other biological control agents
• Environmental and non-target impacts of P. japonica damage and IPM alternatives
• Economic assessment of P. japonica invasions and IPM solutions

We are also pleased to have Dr. Daniel Potter, University of Kentucky (US), serve in an honorary role as Topic Coordinator, and offer advice to the project, via his 43 years of experience and knowledge of P. japonica biology and ecology.

Image: Popillia japonica adult, parasitized by the tachinid, Istocheta aldrichi (white eggs) for biological control
(Mark Holle, www.FruitEdge.umn.edu)