This provides the base for adequate responses to counteract the spread of the invasive pest. Control tools and measures developed within IPM-Popillia will provide a choice of control options for adults and larvae of P. japonica, at sites with high and low population densities, in crop and non-crop environments. This ensures the availability of an adequate response to any future incidence of P. japonica in Europe
Activities
The activities of IPM-Popillia will contribute to the understanding of drivers of pest/ disease emergence, including the influence of climate change
• The phylogeographic analysis will help to clarify the source and hypothetical route of invasion of P. japonica for each major event of introduction (USA, Azores, Italy, and Switzerland)
• Scouting P. japonica during packaging, storage, and transport of agricultural products in the outbreak area will show the relevance of anthropogenic spread of the pest with the trade of goods
• Multiscale spatial representation of factors potentially driving the spread of P. japonica, like climate, landscape features, or control measures, and regression of occurrence of the new pest on preprocessed factors, will identify the most influential drivers of P. japonica occurrence
• Food web studies and the assessment of functional biodiversity of soils will help to understand the key biotic factors that, on one hand, foster or impede P. japonica establishment and population development in a newly invaded area and, on the other hand, affect the development and establishment of antagonists.
• The influence of climate change on the distribution of P. japonica has already been studied on a global scale in a previous study (Kistner-Thomas 2019). Conclusions of this study (e.g. on a change in the voltinism of P. japonica) will feed into the risk-based surveillance strategy of the pest developed in IPM-Popillia
The activities will contribute to the development of efficient tools for the detection of pests/ diseases
• The development of remote-controlled, camera assisted monitoring traps, and machine learning algorithms for P. japonica determination will make monitoring of the pest more efficient, faster and more convenient (automatic alerts elicited from recognition software immediately after detection of a P. japonica specimen)
• A citizen science approach with a smartphone app and an interactive website will involve the public in pest scouting and provides unrivaled spatial monitoring of P. japonica and other relevant species as open data.
• A surveillance strategy based on risk maps provides guidance for the optimal spatial deployment of sentinels for efficient P. japonica monitoring. Traps will be installed in places with the highest risk of P. japonica occurrence, making the monitoring system more reliable
The activities will contribute to the development of efficient tools for the prevention and control of pests/ diseases
A range of control measures will be developed, to enable control of larvae and adults of P. japonica, in different kinds of crops and habitats, at high and low population densities. This “IPM-Toolbox” contains the following measures
• Treatment of potted plants with entomopathogenic nematodes, fungi, or bacteria to prevent the spread of the new pest with the trade of plants
• Development of tools for treatments of grasslands with nematodes and fungi to reduce larval populations in infested zones
• Development of “attract-and-kill”, with long-lasting insecticide-treated nets (LLINs), and “attract-and-infest”, with entomopathogenic fungi in autodissemination traps, for situations where larval populations cannot be treated
• Development of low-risk spray applications, using repellents, feeding deterrents, and biocontrol agents, for situations where high population densities of P. japonica adults threaten agricultural crops and enlarge migration pressure of the Japanese beetles
• Analysis of the effects of soil microbial and (micro-)arthropod communities on the establishment and persistence of biocontrol agents will improve the efficacy of the biocontrol applications
• Genomic data, integrated with a comparative analysis of gene expression between non-treated and treated specimens, will unveil the molecular mechanisms which regulate the efficiency of treatments on P. japonica and its response (development of resistance) to biocontrol strategies
The activities will contribute to the development of environmentally sound solutions for effective pest/ disease management in farming and forestry in line with the principles of Integrated Pest Management (IPM) within a systems approach
• Efficient and economically feasible measures of the “IPM Toolbox” will be implemented in an IPM strategy for P. japonica in Europe. The systems approach of this strategy includes a variety of biological and biotechnical measures against adults and larval populations, in crop and non-crop habitats, in areas with low and high population densities
• The IPM strategy will be flexible and provide an adequate bundle of measures for any situation in the course of an invasion process, starting with impeding population establishment after first incidence and ending with reducing population densities and protecting crops in P. japonica in infested zones. It will be applicable in the outbreak area and on a wider European scale
• Measures developed in the course of IPM-Popillia will be examined for their compliance with the principles of Integrated Pest Management, e.g. by assessment of effects of LLINs on non-target insects, and effects of biocontrol applications on soil microbiome and (micro-) arthropods
• Economic impact of P. japonica on forestry is probably negligible, but the nutritional resources of forestry plants are an important factor facilitating the further spread of the pest. Our integrative approach includes tools (e.g. attract-and-infest or attract-and-kill approaches mentioned above), which are decidedly suitable for forestry applications
The activities will contribute to the reduction of economic, social, and/or environmental losses for the EU
• Application of the IPM tools and strategies against P. japonica provided by the project will help to reduce economic loss in production and trade of agricultural crops, like wine, fruit trees, soft berries, ornamental plants, maize, or soybean
• The IPM-Toolbox will also contain measures suitable for control of P. japonica larvae in non-crop areas, e.g. in forests or forest margins, private gardens, urban lawns, golf courses, and sports fields. They will be valuable alternatives to pesticide treatments and help to prevent social and environmental losses
• Economic and socioeconomic evaluation of the P. japonica invasion, as well as of the measures developed to counteract the control of this regulated pest, will ensure that the plans for management of the new pest in the EU are sustainable
The activities will contribute to supporting relevant EU plant health policies
• The IPM strategy developed in IPM-Popillia will be disseminated as a concise policy advice report. It will help decision-makers in plant health to manage the actual outbreak, and provide policy support for future quarantine pest introductions
In the longer term, the activities will help the agricultural/forestry sector to remain productive and contribute to sustainable agriculture and/or forest health.
• The crops and areas at risk of P. japonica invasion in Europe include more the 3 million hectares of vine, more than 5.5 million hectares of soybean, more than 17 million hectares of maize, 350’000 hectares of plums, and 170’000 hectares of cherries, to name a few (estimates based on FAOstat, 2017). The measures developed in IPM-Popillia help (i) to prevent or at least slow down the spread of the invasive pest into these crops and areas, and (ii) to impede the buildup of high population densities in infested areas, thereby preventing severe yield loss
• Measures of containment and control of an invasive pest may stay in force for decades rather than years only (see the example of P. japonica in the US or of Diabrotica virgifera in Europe). Longer-term outputs of IPM-Popillia are therefore likely to contribute to the productivity and sustainability of the European agricultural and forestry sector in a similar time span.
