Researcher Discovers Link in Understanding Pest

Kelly Marshall

Nematodes are a billion dollar threat to agriculture each year.  Plant scientists at the University of Missouri and the University of Bonn in Germany have discovered that nematodes use a specific hormone to help them feed on the plant.  This discovering could allow scientist to develop plants with resistance to the pests.

Mitchum-Melissa-180x120“Cell cycle regulation is a key aspect of plant development and one of the first events altered during the formation of the feeding sites nematodes use to acquire nutrients from host plants,” said Melissa Goellner Mitchum, a researcher in the Bond Life Sciences Center and an associate professor in the Division of Plant Sciences at MU. “These discoveries led scientists to suspect that cytokinin, a hormone that promotes cell division in plants, might play a key role in feeding site formation for nematode parasites.”

“As part of our research, we examined the activation of different components of the cytokinin pathway in response to nematode infection,” says Carola De La Torre, a postdoctoral fellow at MU who worked with Mitchum. “Also, we evaluated numerous plants that lacked the presence of these components and found that most of these plants were less susceptible to nematode infection. These results suggested to us that these little worms are not only utilizing parts of a plant hormonal pathway that is important for plant growth and development, but they also are doing it in a way that allows them to cause disease.”

Mitchum’s team partnered with Florian Grundler’s group at Rheinische Friedrich-Wilhelms-University of Bonn, Germany, who further analyzed the connection between cytokinin and nematodes. Using advanced genetic tools, they discovered that nematodes create their own form of plant cytokinin and that, by secreting the hormone into the plant, they actively control the cell cycle leading to the production of ideal feeding sites to support their development. These findings show the ability of an animal to synthesize and secrete a functional plant hormone to establish long-term parasitism.

“Understanding how plant-parasitic nematodes modulate host plants to their own benefit is an essential first step in finding new technologies needed to develop crop plants with enhanced resistance to these devastating agricultural pests,” Mitchum said.

Researchers from Palacký University and the Institute of Experimental Botany Academy of Sciences of the Czech Republic; the Institute of Biology and Applied Genetics and the Dahlem Centre of Plant Sciences, Freie Universität in Berlin, Germany; the Department of Botany, Warsaw University of Life Sciences in Warsaw, Poland; and the Department of Biology and the Graduate School of Science at Osaka University in Osaka, Japan all contributed to this study.

Education, Research