"Root-colonizing" microbes may not be confined to the soil; instead, populations over large regions may be linked by various biotic and abiotic transport systems whose strength, perhaps, is limited by the densities achieved locally. Research will develop and validate an epidemiological model that links local processes of growth and movement from single root systems to larger scale process of transport, colonization, and persistence. The work will be conducted with a specific model system - a bacterium, engineered with unique markers to facilitate fluid experimentation, and an insect that feeds on corn roots- but the questions, experimental approach, statistics and models are more general. This work takes on special significance since bacteria are being engineered for many environmental and agricultural functions, and will not be endowed with trivial or ecologically irrelevant traits.
