McSpadden Gardener Lab - Research

We study the ecology of plant-associated microorganisms, especially those that contribute to the development and suppression of plant diseases.
The specific goals of the research are to: (i) characterize the abundance, diversity, and activities of genes and microorganisms associated with plant growth promotion and plant disease suppression, (ii) determine the impact of different farm management practices and other environmental variables on the occurrence and activities of those functionally important microbial populations, and (iii) develop cost-effective biological control strategies that improve agricultural sustainability, productivity, and profitability.


Current researchCurrent research involves molecular characterization of microbial populations that colonize plants and their responses to different farm management practices. In the lab, we use several different methods to study the abundance, diversity, and activities of specific target populations. We also profile plant-associated microbial communities using ribosomal and functional gene targets to identify and recover microbial populations that may contribute to changes in plant health or variations in food quality or safety. Once identified, we use marker assisted selection to recover representative isolates and study their activities under controlled conditions and develop those with useful activities into new products.

Initially, our lab focused on studying the ecology and biocontrol efficacy of DAPG-producing Pseudomonas spp. as well as several Bacillus spp. known to act as biocontrol agents and/or induce plant host defense pathways (Biological Control of Plant Pathogens). More recently, we have conducted related studies on newly discovered species that contribute to pathogen suppression in various contexts. And, we continue to look for opportunities to evaluate and develop new microbial inoculants as substitutes for petroleum-based chemical inputs for agriculture. The ultimate goal of this research is to improve the agricultural sustainability through the discovery of new active ingredients that can be used in the development of biopesticides, biofertilizers, and other microbial inoculants.

The ultimate goal of this research is to improve the agricultural sustainability through the discovery of new active ingredients that can be used in the development of biopesticides, biofertilizers, and other microbial inoculants. The laboratory's work is also aimed at training young scientists in how to develop, use, and apply such products for the benefit of producers as well as the environment. To this end, a special topics class is taught every other year to engage students in critical review of literature and practices related to byproduct use. The class includes interviews and field trips to give students direct experience with the use of biopesticides and similar products in commercial production.

Plant associated microbesFuture avenues of research will characterize the biogeography of other plant-associated microbes, the disease-reducing molecular mechanisms expressed by different biocontrol bacteria, and the interactions among host, biocontrol agent, and pathogen.

Given the founding mission of this Land Grant University, my chosen research systems include three of Ohio's most valuable and widely-planted crops as well as other high-value fruit, vegetable, and nursery crops. And, all are aimed at improving the profitability and sustainability of small- to medium-sized family farms, especially those who choose to operate within a certified organic framework.