Professor Richard Immink, an expert in the field of plant growth and development at Wageningen UR, and three other partners have together qualified for a Human Frontier Science Program (HFSP) grant worth $1.35 million. They are going to use this funding to develop a model that will be better able to predict the three-way interaction between a pathogen, vector (a transmitter of disease, for example the malaria mosquito) and host.
Free ride in sap with insect
In the natural environment there are various disease-causing organisms that attack plants. One of these is the phytoplasma bacterium, which is able to completely take over the development of a plant, turning it into a ‘zombie’. It is then totally at the service of these bacteria and certain insects. These insects are very important because bacteria cannot spread themselves from plant to plant, so they are completely dependent on the insect vectors. By ‘free riding’ in the sap that insects suck from plants, phytoplasma bacteria can infect new plants, thus spreading themselves further. This is known as a three-way interaction. In this particular case, the interaction is between the pathogenic phytoplasma bacteria, the insect vector and the host plant.
A fight between genes
The hypothesis put forward by Immink and the other research partners is that the interaction between a pathogen, vector and host is not a fight between individual organisms but between specific genes. To understand this better they are going to build a mathematical model over the next four years. This will simulate the interaction of phytoplasmas, vector and host. They will be filling and validating this model with data from field studies performed during the research.
A better understanding of three-way interactions
The model is expected to be applicable to other situations and also to be suitable for predicting the dynamics of other three-way interactions as in the case of malaria, where the interaction involves the mosquito, the malaria virus and a host such as a human being or bird.
This HFSP grant research builds on a scientific publication written last year by Professor Saskia Hogenhout and Richard Immink on what are known as zombie plants. In that article the scientists explained how a specific bacterial parasite, which causes problems in the development of crops like rapeseed, is able to manipulate plants in such a way that they produce more leaves instead of flowers.
Professor Saskia Hogenhout of the John Innes Centre in England is leading the project. Other researchers work at the Institute of Plant Protection in Poznan, Poland and at the University of Wisconsin in the United States.