Many fungi are harmful to human interests:
can cause human disease, either directly or through their toxins
can cause diseases of plants and animals that humans are intersted in (e.g. crops, etc.)
cause rot and contamination of foods
can destroy almost every kind of manufactured good-- with the exception of plastics and some pesticides
Many fungi cause problems because we are in competition with them for some limited resources.
See also “Fungal Diseases that must be overcome to have a traditional Thanksgiving Dinner” at <a href-=“http://www.wisc.edu/botany/fungi/thanks.html”> http://www.wisc.edu/botany/fungi/thanks.html</a>