Plant pathologist awarded grant to aid global study of seedborne pathogens

October 03, 2019

UNIVERSITY PARK, Pa. — A nearly $4 million grant awarded to Penn State will support an interdisciplinary, multi-university team of researchers as they explore bacterial pathogens causing leaf spot diseases that are damaging valuable agricultural crops such as watermelon and pumpkin.

The grant, from the U.S. Department of Agriculture's National Institute of Food and Agriculture, will be supplemented by nearly $3 million in matching investments from seed companies and associated industries and over $1 million from the universities involved, according to project director Carolee Bull, professor and head of the Department of Plant Pathology and Environmental Microbiology in the College of Agricultural Sciences.

In addition to advancing the science the research will have real-world impacts, and members of the industry are equal partners in the research and support for the project.

“Beets, Swiss chard, squash, cantaloupe, watermelon, zucchini and pumpkin are among the victims of bacterial pathogens that these crops carry to the field in and on their seeds,” said Bull, who also serves as the director of Penn State’s Microbiome Center, which is housed in the Huck Institutes of the Life Sciences.

“These diseases have devastating effects on these crops. Home gardeners also may be plagued by these diseases in their home plots. We have put together a world-class team and are thrilled that the USDA and the international seed industry recognize the value of our research and the important contributions it will have on global seed and plant health.”

Bull explained that seedborne bacterial leaf spot diseases are caused by a group of related bacteria in the species P. syringae, which contaminate or infect seeds or can infect plants via wounds or natural openings. Once the bacterium enters a plant, it multiplies and causes black lesions that reduce the plant’s ability to photosynthesize and make its own nutrients to grow.

These diseases have increased in frequency and are recognized as a major economic threat to agricultural production. In fact, in 2017, the prevalence of bacterial leaf spot diseases was 75%, and the average incidence was 80% in New York beets.

Likewise, from 2013 to 2014, disease outbreaks caused by P. syringae destroyed an estimated 8,000 acres of watermelon and squash in Florida, including major commercial production areas. Seed infestation has been identified as the main factor contributing to both long distance dissemination of the pathogen and its introduction into new geographic areas.

Bull will serve as project director for a team of university, government and industry scientists, including postdoctoral scholars and graduate students, as they embark on a four-year study of the biology and epidemiology of the pathogens causing this disease in crops grown for seed and those grown for food. The researchers will study seed microbiomes and use diagnostic metagenomic and other approaches to detect the pathogens in and on the seed.

Carolee Bull and graduate student

Carolee Bull, professor and head of the Department of Plant Pathology and Environmental Microbiology, and graduate student Lindsay Boyd sample for biological control agents against seedborne pathogens in Batavia, New York. 

IMAGE: Julie Kikkert

The group’s goals include developing resistant plant lines for seed and crop production and evaluating whether the traits needed for seed-crop resistance are the same as those needed for food-crop resistance; improving integrated pest management strategies for seed and food crops using new technologies, including effective biological controls; and identifying biological and genetic data that will enable the development of accurate and sensitive pathogen detection and quantification methods.

In addition, Claudia Schmidt, assistant professor of agricultural economics, will work with other team members to create a cost analysis for implementing practices developed and will share the findings with growers, seed companies, scientists, students and the public.

A key feature of the grant is that early career faculty members, postdoctoral scholars and graduate students will receive formal mentorship from a variety of sources. This is due, in part, to Bull’s expertise in this area as recognized by national awards.

“It was truly a rewarding experience to learn project development skills from Dr. Bull and the grant team, including organizing a multi-disciplinary team of scientists from academia and industry, meticulous project planning and, most importantly, grant-writing skills,” said Neha Potnis of Auburn University, who will serve as principal investigator of the project.

Other researchers involved in the study are Beth Gugino, Samuel Martins, Christina Call and Audrey Maretzki, Penn State; Eric Newberry, Auburn University; Jeffrey Jones and Mathews Paret, University of Florida; Lindsey du Toit and Lydia Tymon, Washington State University; Sarah Pethybridge, Cornell University; Irwin Goldman, University of Wisconsin; W. Patrick Wechter, USDA Agricultural Research Station, Charleston, South Carolina; Alejandra Huerta, University of North Carolina; José Pablo Dundore-Arias, California State University, Monterey Bay; and Teresa Coutinho, University of Pretoria, South Africa.

Industry partners include Sakata Seed Co., Love Beets USA, American Seed Trade Association, Monsanto Vegetable Seeds, California Seed and Plant Laboratory Inc., and Starke Ayres Seed.

(Media Contacts)

Last Updated October 03, 2019