Project GREEEN advancing research on harmful plant insects
With vibrant and valuable forestry and plant agriculture industries in Michigan, there are a multitude of reasons forest managers and growers want to protect plants.
According to the Michigan Department of Natural Resources (MDNR), forest products create roughly $22 billion in total economic output annually for the state. The Michigan Department of Agriculture and Rural Development (MDARD) reports $753 million as the total economic impact of the Michigan fruit industry, along with $428.2 million for vegetables and $1.26 billion for nursery and landscape crops.
Needless to say, plants are big business in Michigan. So when they are threatened by native and invasive insects, Michigan State University researchers are called upon to assist with the problem.
Using resources from Project GREEEN — Michigan’s plant agriculture initiative through MSU, MDARD and the Plant Coalition — MSU scientists have been addressing emerging and pervasive insect challenges for more than 25 years across an array of plant industries. These preliminary findings have often led to large federal grants from agencies such as the U.S. Forest Service and the U.S. Department of Agriculture's (USDA) National Institute of Food and Agriculture to further explore the issues...
Not unlike EAB, the Michigan tree fruit industry has experienced a number of problematic pests over the years. Arguably the most difficult to manage has been spotted wing drosophila (SWD), a small vinegar fly native to Asia that’s about the size of a grain of rice.
First discovered in West Michigan in 2010 by MSU researchers, SWD has presented some unique challenges to growers of soft-fleshed fruits such as berries and cherries. MSU scientists have been at the forefront of addressing the problem, using Project GREEEN funds to learn more about SWD, its behavior and ways to protect tree fruit.
Among the projects are work of Rufus Isaacs, a University Distinguished Professor in the Department of Entomology, and EEB core faculty, who was one of the first to discover the pest in Michigan. Working closely with him throughout that time has been Julianna Wilson, an assistant professor in the Department of Entomology. Prior to her career at MSU, Wilson, who also serves as a tree fruit specialist through MSU Extension, studied in Isaacs’ lab as a graduate student and postdoctoral researcher.
Project GREEEN has played a significant role for Isaacs’ and Wilson’s research. Not only has it funded projects, but it has also helped support their positions at the university. Both have received funding and support from MSU AgBioResearch as well.
Initially through Project GREEEN funding, Isaacs, Wilson and the MSU Fruit Team uncovered some unique aspects of SWD population dynamics. While most insects have populations with distinct generations that cause the total number to ebb and flow throughout the year, SWD is different. There may be several generations living at once, causing a population surge that can quickly overwhelm orchards and even surrounding wild fruits.
Using the results of this work and other research, online resources have been created to help growers with SWD identification, pesticide timing and other management strategies.
Some of the newest SWD efforts are testing biological controls with funding from Project GREEEN and an MDARD Specialty Crop Block Grant, among other sources. Alongside Isaacs and Marianna Szucs, an assistant professor in the Department of Entomology, Wilson is investigating the efficacy of releasing the samba wasp in Michigan.
The samba wasp is a parasitoid native to Asia, where it’s a natural predator of SWD. Parasitoids lay eggs in or on a host that, upon hatching as larvae, consume the unlucky insect.
With permission from MDARD and USDA APHIS, Wilson and the team of researchers have released the samba wasp over the past two growing seasons in southwest and northwest Michigan. Wilson and Isaacs have led the efforts to rear enough samba wasps to disperse throughout these areas.
Researchers are evaluating the success of the samba wasp at curbing SWD populations, as well as the wasp’s ability to survive Michigan winters.
“We’ve seen that there simply aren’t enough native Michigan predators to help lower the SWD population, so this is an effort to introduce a species that goes after them directly,” Wilson said. “It’s important to understand that this is a long-term approach, but we are hopeful to see positive results.”
Read the full story in the College of Agriculture and Natural Resources.
