Print PageSeveral recent studies have examined how plant genetics and the environment interact to structure dependent arthropod communities, however little is known about how these factors influence microbial communities, especially plant pathogens. Because pathogens have the potential to alter host performance and survival, which in turn can affect a much larger community, it is important to integrate pathogens into the community genetics perspective. We implemented a reciprocal transplant common garden experiment to quantify the relative strength of host plant genotype (G), environment (E), and their interaction (G:E) in structuring the fungal leaf pathogen community of Populus angustifolia. We also determined whether the broad-sense heritability (H2) of resistance to individual pathogens and to the pathogen community varied between garden environments, and between two field seasons.
Results/Conclusions
Consistent with studies of arthropods at intermediate spatial scales, in both years we found that E explained approximately twice as much variation (35%) in the pathogen community as both G (13%) and G:E (13%). As a result of strong E effects on pathogen communities, the H2 of resistance to the pathogen community was as much as twice as high in one garden as another. Overall, our results indicate that pathogen community composition can change as a result of evolution in P. angustifolia; however, spatial processes will strongly influence these ecological and evolutionary responses.
