A new analytical method for measuring the release of herbicidal compounds from plant roots has been developed by two Ashland University chemistry professors and this method is generating excitement in science labs around the world.
News of the development has become so widespread, in fact, that Dr. Jeff Weidenhamer, trustees’ distinguished professor of chemistry at Ashland University, spent a week in Berlin, Germany, and six weeks in Australia this summer discussing the new method.
“The new method is starting to develop a lot of interest worldwide,” Weidenhamer said. “We had two collaborators from Denmark who worked with us on our first paper. We are hoping this method will be of use to a lot of researchers.”
Weidenhamer and Brian Mohney, associate professor of chemistry at Ashland University, have collaborated with a group from Berlin on the use of this new method and a first research paper from this collaboration is now in review.
Weidenhamer said this development has agricultural applications because it could provide farmers with a way to control and fight weeds in the field through the use of the right cover crops instead of herbicides.
“The goal would be to develop crops that could produce their own herbicide,” Weidenhamer said. “That is why we have been focused on developing these methods and I hope it will lead to insights we have not been able to find in other ways.”
Weidenhamer explained the new method, noting that compounds released by plants roots are absorbed into thin silicone tubing and when solvents are run through the tubing, it produces samples that can be analyzed in the lab. “And, because the tubing does not disturb the roots of the plant in anyway, it does not need to be removed,” he said.
Weidenhamer said he has been working on developing methods for soil analysis since he came to Ashland University in 1989.
“My students and I have studied a number of methods that have not worked as well before arriving on this latest technique. Brian Mohney’s analytical expertise has really helped move the project along,” Weidenhamer said. “Measuring soil concentrations of chemical compounds released by plant roots has been a real interest of mine since my Ph.D. work, where I was working with plants in the Florida Scrub that produce natural herbicides.”
Weidenhamer said Ashland University received a National Science Foundation grant several years ago, which allowed for several students to conduct research during the summer. “This development actually came out of this work with the students here at Ashland University and we are now carrying it forward,” he said.
Weidenhamer received a Fulbright Specialist Award in May of 2011, and is one of more than 400 U.S. faculty and professionals who traveled abroad this year as part of the Fulbright Scholar Program. The program, sponsored by the U.S. Department of State, Bureau of Educational and Cultural Affairs, selects recipients based on academic or professional achievement.
In June, Weidenhamer was invited to present a seminar at the Institute for Biology of the Free University of Berlin by Professor Matthias C. Rillig and Dr. Kathryn Barto, a postdoctoral researcher in his laboratory. Dr. Rillig is an expert on the importance of mycorrhizae, symbiotic fungi that assist plants in taking up nutrients and water from the soil.
“The Berlin group contacted us to work together on this experiment,” Weidenhamer said. “Professor Rillig is one of the experts in this field and is very much interested in what goes on in the soil for plant growth.”
As part of the Germany trip, Weidenhamer presented a talk titled “Analytical Strategies for Ecologically Active Phytochemicals” and then spent three days in discussion with the German researchers regarding further experiments and development of research proposals.
Weidenhamer said he hopes that the collaboration on this research paper with the Berlin group might lead to an opportunity for students to have additional internships either at Ashland or in Berlin.
Weidenhamer said results of the work at Ashland University were given to the Berlin group and they collected samples and sent them back here for the analysis. “While I was over there, we talked about a number of follow up experiments, how they will collect additional samples and how we would do the analysis here in Ashland,” he said.
“I had a great time over there. They have very nice facilities and the German educational system is very different than ours but they are doing some very good work in the labs,” he said. “I never expected that I would go to a place like Berlin with my scientific research. I consider it quite an opportunity to get an invitation like this and see a part of the world that I would not have been able to see otherwise.”
During his six weeks in Australia, Weidenhamer spent most of his time at Charles Sturt University in Wagga Wagga working with Professor Leslie Weston, an expert on herbicidal natural products who has done extensive research on herbicidal compounds prodiced by sorghum and fescue. At CSU, Weidenhamer presented a seminar on his work titled “Developing New Analytical Methods for Root Exudates in Soil” and also participated in a workshop on “Rhizosphere Interactions.”
Between these presentations, there were conversations with many individuals about studying rhizosphere interactions, which are interactions that take place in the soil immediately surrounding the plant root.
CSU’s new rhizolysimeter facility was dedicated the day after Weidenhamer arrived, and Weidenhamer called the facility “a very unique resource for studying below ground processes and interactions among plants.
Weidenhamer also attended the International Botanical Congress held in Melbourne and presented a talk (co-authored with Brian Mohney) on July 28 in a symposium on the rhizosphere. Before leaving, he presented a seminar in Canberra to the Plant Industries group of the Commonwealth Scientific and Industrial Research Organization (CSIRO), which is Australia’s national science agency.
Ashland University (www.ashland.edu) is a mid-sized, private university conveniently located a short distance from Akron, Cleveland and Columbus, Ohio. Ashland University values the individual student and offers a unique educational experience that combines the challenge of strong, applied academic programs with a faculty and staff who build nurturing relationships with their students.