Nematodes Manipulate Auxin Transport to Obtain Food

Researchers at the Flanders Institute for Biotechnology and Ghent University are one step closer to developing novel crop plants resistant to nematode pests. They have shown that nematodes are able to manipulate the transport of the phytohormone auxin in order to force the plant to produce food for them. Auxin coordinates numerous growth and behavioral processes in the plant life cycle, including cell division and elongation, phloem and xylem differentiation, and growth of root hairs.

During infection, nematodes inject a cocktail of proteins in a particular cell in the plant vascular bundle. These proteins cause the plant cell to merge with neighboring cells and to start producing food for the nematode. Auxin initially accumulates at the site of infection. Concentration of auxin then increases in the neighboring plant cells when the feeding site needs to grow.

Wim Grunewald and his colleagues were able to show that nematodes knock out the expression of certain plant PIN proteins. PIN facilitates the transfer auxin from one cell to another. The discovery could lead to the development of ways to prevent nematode infection for example, by locally counteracting the nematodes’ manipulation of auxin transport. Nematodes are usually controlled by applying methyl bromide, pesticide that has been banned for use in the United States because of its severe negative effects to the environment.

Read the complete article at http://www.vib.be/VIB/EN/ The paper published by PLoS Pathogens is available at http://dx.doi.org/10.1371/journal.ppat.1000266