[1][2] Fungi can cause serious damage in agriculture, resulting in losses of yield and quality.
Fungicides are also used to control oomycetes, which are not taxonomically/genetically fungi, although sharing similar methods of infecting plants.
Classifications are based on inorganic (elemental sulfur and copper salts) vs organic, chemical structures (dithiocarbamates vs phthalimides), and, most successfully, mechanism of action (MOA).
Traditional fungicides are simple inorganic compounds like sulfur,[5] and copper salts.
These additional fungicides typically belong to the same chemical family, act in the same way, or have a similar mechanism for detoxification.
For example, Black Sigatoka, an economically important pathogen of banana, is resistant to the QoI fungicides, due to a single nucleotide change resulting in the replacement of one amino acid (glycine) by another (alanine) in the target protein of the QoI fungicides, cytochrome b.
The pathogen had five ABC-type transporters with overlapping substrate specificities that together work to pump toxic chemicals out of the cell.
Fungicides that are at risk of losing their potency due to resistance include Strobilurins such as azoxystrobin.
[12] Cross-resistance can occur because the active ingredients share a common mode of action.
[15] Fungicide residues have been found on food for human consumption, mostly from post-harvest treatments.
[17] Ziram is also a fungicide that is toxic to humans with long-term exposure, and fatal if ingested.