Abstract: Biocontrol of bee lawns in parks and landscapes, LCCMR 2021-2024

Project Manager Name: Vera Krischik
Project Manager Email address: [email protected]
Project Title: Biocontrol of bee lawns and park lands
Proposal ID: 2021-164, LCCMR 2021-2024

JB on coneflower
Japanese beetle on coneflower (S. Wold-Burkness, UMN)

Economic and environmental costs in managing JB are high. It was estimated to cost in the US more than $460 million a year and an additional $156 million in renovating or replacing damaged turf or ornamental plants (Potter and Held 2002). Since JB causes serious environmental and economic damage, there have been many reviews on its management (Jackson and Klein 2006; Potter and Held 2002; Vittum et al. 1999; Potter et al. 1998). JB management is important in MN due to the economic costs of JB reducing plant quality and plant sale to other states, and due to the threat of exporting JB contaminated  plants to other states.  Federal and MN JB quarantine programs and JB surveillance are directed at the shipment of nursery plants, as well as the movement of JB from airports to 9 JB-free western states (USDA 1996, 2016, 2017; CONGA 2017).

Previous MDA sponsored biocontrol programs to manage JB were not successful. Although released by the MDA in the 1990's, the tachinid Istocheta aldrichi that parasitizes adults, and a wasp Tiphia vernalis that parasitizes overwintering grubs did not cause much JB mortality and were not widely established (Jackson and Klein 2006).

In addition, previous management tactics for JB are not currently working. Milky spore disease, Paenibacillus (=Bacillus) popilliae, was widely used in the 1950's in the Eastern US (Fleming 1968), but has not shown recently to be effective. The neonicotinoid imidacloprid that is widely used on turf for JB grubs, is about to be banned for use on lawns by the EPA (https://www.epa.gov/pollinator-protection/epa-actions-protect-pollinators).

There is much public, state, and commodity group interest in managing JB. It is an economic importance to MN to manage JB as it is a quarantine pest in the western US which requires the MSP airport and nurseries to adhere to strict quarantine guidelines and demonstrate that plants are JB free when shipped. The MNLA (Jim Calkins), the Golf Course Superintendents Association (Jack MacKenzie), and Minneapolis Park and Rec (Jeremy Barrick) have indicated support of this project. Krischik published articles on JB in two MN commodity journals; Krischik provided a webinar on JB to MNLA; Krischik provide a segment on JB to Almanac, a MN PBS program. The MDA was contacted about working with us on the project. Dr. Raj Mann of the Pesticide Management Division is interested in ways to manage JB that does not impact pollinators. We discussed this program with Mark Abrahamson of Plant Protection Division MDA. An advisory board with members from MSU, MN DNR, MDA, Golf Course Superintendents Association, MNLA, and Minneapolis Parks and Recreation Board and a list serve of interested participants has been organized. The PI Krischik has been a Scientific Advisor and appointed member of the Minneapolis IPM program to reduce pesticide use in parks.

The purpose of this research is to develop new management tactics to reduce economic and environmental damage caused by the exotic JB with the use of pathogens and JB traps to spread the pathogens. The outcome is to reduce JB numbers locally and to slow its spread around the state of MN. Current insecticides used to control JB grubs in pollinator bee lawns and in restorations have negative effects on pollinators. The research and outreach programs will be used to establish long term and short term management of the exotic pest.

The long term outcome is to establish an endemic pathogen to kill JB. Ovavesicula popilliae was first described in Connecticut and infects JB malpighian tubules and spreads systemically (Andreadis and Hanula 1987). It has since been found infecting JB in Michigan (Cappaert and Smitley 2002), Kentucky (Redmond and Potter 2010), and Arkansas (Petty et al. 2012). Research show that in 6 years after introduction, the fungus kills 15 percent of the JB grubs (see graphs in methods).

The short term outcome is to test current EPA registered microbial insecticides in the lab and field for efficacy of killing JB adults and grubs. Outreach and educational demonstration projects at parks will promote the IPM programs.

HYPOTHESES

Hypothesis 1. Long term management, Survey MN for pathogens, establish pathogens at 10 sites

We will survey 40 sites in MN (from Alexandria to Chaska to Stillwater to Burnsville) for two years from Aug to Sept for the presence of JB and O. popilliae. The pathogens will be identified morphologically and through ELISA tests through collaborations with Dr. Dave Smitley of Michigan State University.  We will use 10 of these sites to introduce O. popilliae that will be chosen thru discussion with the supervisors who will ensure that JB populations will not be controlled so that the pathogen can build up and we can  survey the sites each year. These research sites will become nursery sites (donor sites) to which we will send our collaborators to collect infected JB for release in other sites (receptor sites) around MN. Since the pathogen moves slowly on its own, it is necessary for our collaborators to help disseminate the pathogen to new sites. JB mortality will be measure through overwintering success and number of eggs laid by infected adults.

We will also monitor the use of JB in bee lawns thru trapping at established bee lawns, such as the Minnesota Arboretum, University of Minnesota, Minneapolis Park and Recreation Board, Lawns to Legume Program, and other sites. We will ask identify collaborators at these sites to add to our advisory board. We will release the pathogen in bee lawns at 8 sites and monitor it for the 3 year grant. We will work directly with the established bee lawn programs to setup demonstration sites about proper insecticide use. For instance, in bee lawns and backyards the biorational insecticides studied in this research need to be used to protect pollinators and NOT the bee friendly EPA approved chlorantraniliprole that is highly toxic to butterflies. Our acute and chronic butterfly and bee research from the 2017-2020 LCCMR has been submitted in March 2021 to Environmental Toxicology, entitled “Survival and growth of monarch, Danaus plexippus, and painted lady, Vanessa cardui butterflies on four insecticides”, that demonstrates the extreme low toxicity of chlorantraniliprole to butterflies.

Once established, we will monitor the yearly spread of the pathogen in the receptor sites.  We will work with Drs. Raj Mann and Mark Abrahamson of the MDA to approve the release of O. popilliae at 10 sites with high JB populations, 4 demonstration sites at parks and 6 golf courses. We will work with state and federal agencies to obtain permits to move the pathogen around Minnesota for release. These introductions will serve as nursery sites (donor sites) for spreading the pathogen throughout Minnesota. In order to quantify pathogen spread, we will monitor pathogen infection levels at the introduction sites (10 sites: 4 parks and 6 golf courses) and sites (non-receptor sites) located 5 - 10 km away. We will work with outreach groups such as Master Gardeners and Master Naturalists to distribute pathogens in their local areas (receptor sites) and to train them to yearly monitor the percent of JB that have pathogens.

Hypothesis 2. Short term management, Bioassays on JB and pollinators, develop IPM program

Pollinator friendly IPM programs need to be developed with cultural and insecticide management recommendations for bee lawns and parks in MN. The efficacy of new EPA approved microbial insecticides and new conventional insecticides for killing JB will be researched. Also, It will be determined if these insecticides are friendly to bees when used for JB grub and adults.  EPA registered microbial insecticides for bioassays are GrubGone (Bacillus thuringiensis galleriae, BTG, recently available), a soil-applied fungus (Beauveria bassiana), parasitic nematodes (Steinernema scarabaei, Nemagard, recently available), and bee friendly Acelepryn (chlorantraniliprole) compared to standard neonictoinoids (imidacloprid, MeritG and clothianidin, ArenaG). The non-target effects of these microbial insecticides on Bombus impatens, bumblebees and Osmia, mason bees, will be studied. We have done these bioassays many times for our research and are proficient and collect viable data on the effects of label rates of insecticides on bee colony health. In addition, we will study whether commercially available JB traps can be used to disseminate BTG, which will serve as a model system for dispersing Ovavesicula. We will evaluate the correct timing for applying these insecticides and the amount of control that can be achieved (percent pathogen infection).

OUTREACH

Install demonstration education programs at key parks to promote the IPM and biocontrol program.

Outreach demonstration sites and field days. By summer of year 2, we will have established the 10 pathogen introduction sites (6 golf courses and 4 demonstration projects at parks). At the 4 park demonstration sites we will convene Field Days with professionals, consumers, Master Gardeners, and Master Naturalists and provide information on the program and if possible provide infected JB to create satellite nurseries in local areas. A website, IPM bulletins, and workshops will support the educational program.