autonomous biological control" of coffee rust.
Nature is a complex equilibrium. This is an example of what can happen when one attempts to modify this equilibrium.
"Coffee rust is a fungus, but spraying fungicides to kill it may inadvertently destroy natural fungal enemies of coffee rust that help to keep it in check.
And the ongoing abandonment of traditional shade-growing techniques, in which coffee is grown beneath a canopy of trees, likely reduces the diversity and abundance of beneficial insects and opens the plantations to winds that help disperse coffee rust spores, according to U-M ecologist John Vandermeer and his co-authors, Ivette Perfecto and Doug Jackson.
"Small, seemingly trivial changes in environmental conditions can generate dramatic shifts in the underlying dynamics of the disease," the researchers wrote. "The techniques of so-called modernization (e.g., cutting shade, applying fungicides) may gradually eliminate what has been effectively autonomous biological control" of coffee rust.
"A movement back toward more shaded systems, with minimal application of agrochemicals, might be an appropriate recommendation for coffee farmers in the region.""
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