Abstract
Soil biologists acknowledge that soil is structurally heterogeneous and that the soil environment varies with time. For practical reasons, most experimental work on soilborne plant pathogens implicitly assumes that soil is homogeneous, or is done under constant conditions. Recently soil scientists have developed powerful new tools for describing soil structural heterogeneity. In this paper we discuss the potential for one of these, fractal geometry, to be used in situations such as determining the relationship between soil texture and disease prevalence, or between tillage and disease severity. The more widespread use of soil wetness duration as a measure of soil water status in field and pot experiments under fluctuating moisture conditions is advocated.
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Backhous, D., Nehl, D.B. Fractal geometry and soil wetness duration as tools for quantifying spatial and temporal heterogeneity of soil in plant pathology. Australasian Plant Pathology 28, 27–33 (1999). https://doi.org/10.1071/AP99004
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DOI: https://doi.org/10.1071/AP99004