Soil microbes play key roles in plant health, both through the detrimental effects of plant pathogens and the beneficial effects of increased access to essential soil resources through associations with bacterial and fungal mutualists. As a result the viability and reproductive success of plant populations depends upon the composition of the soil community and the long-term trajectory of terrestrial plant productivity and community composition depends upon the dynamics within the soil microbial community. Experimental manipulations have demonstrated that the soil microbial community changes with its local plant host and often this change leads to a decline in performance of that host. In agricultural crops, for example, the change in microbial community following mono-cropping leads to a yield decline, thereby motivating a strategy of crop rotation. Recent experimental work suggests that these same dynamics can contribute to the replacement of plant species and the maintenance of diversity in unmanaged plant communities. While there is strong evidence for these processes, this work has not been integrated into a comprehensive understanding of the long-term potential for microbial dynamics to drive plant community patterns. The goal of this research project is to synthesize the evidence on the ecology of plant-microbe interactions within a monograph. The monograph will build from the determinants of virulence in plant pathogens and of stability of benefits from plant mutualists toward a framework that predicts microbial mediation of plant dynamics. This framework will allow predictions of changes of plant community composition across time, and across environmental perturbations.
This project will produce a monograph that will serve as a comprehensive synthesis of a growing area of plant ecology and will thereby be useful for undergraduate and graduate training. The monograph will motivate further work on the plant-microbe interactions and their consequences, and the framework developed will facilitate prediction of responses of terrestrial communities to anthropogenic disturbance, such as climate change.
