Mike Dixon Guest SES Seminar Series

"Improving Irrigation Management Strategies in Ontario's Tree Nurseries" High mortality rates among most species of nursery trees after transplanting is generally blamed on water stress imposed by a variety of soil and other environmental conditions. This study examined the efficacy of a consortium of micorrhyzae, comprised of twenty species of both endo and ecto mycorrhyzae, to mitigate drought stress and reduce irrigation requirements when inoculated into the root zone of recently transplanted trees. The water status of the trees was monitored with automated stem psychrometers measuring stem water potential at thirty minute intervals for at least two weeks after transplanting. The treated trees exhibited significant reduction in mid-day water stress and enhancement of overnight rehydration as shown by diurnal patterns of water stress and recovery. The water potential integral (MPa-Hrs) proved to be a very effective analytical tool for comparing treatments and will provide a unique quantitative means of assessing plant-environment interaction as we proceed to modify irrigation management strategies in the nursery sector.

Dr. Dixon is also the project leader for the research team at Guelph investigating the biofiltration of indoor air as a method of alleviating what is commonly known as “sick building syndrome”.

Off campus he is the Technical Exchange Coordinator for the International Advanced Life Support Working Group (IALSWG) which is a strategic planning group coordinating information and personnel exchanges among international space agencies such as CSA (Canadian), NASA American), ESA (European), RSA (Russian) and JAXA (Japanese).  He also has served 2 terms as Chair of the Space Exploration Advisory Committee of the Canadian Space Agency (CSA), sat on their Senior Space Science Advisory Committee and is a member of the Life Sciences and Technical Committee of the American Institute of Aeronautics and Astronautics.