Fungicides are biocidal chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores.〔(Interaction of 2,4,5-trich|orophenylsulphonylmethyl thiocyanate with fungal spores )〕 Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality, and profit. Fungicides are used both in agriculture and to fight fungal infections in animals. Chemicals used to control oomycetes, which are not fungi, are also referred to as fungicides, as oomycetes use the same mechanisms as fungi to infect plants.〔Latijnhouwers M, de Wit PJ, Govers F. ''Oomycetes and fungi: similar weaponry to attack plants.'' Trends in Microbiology Volume 11 462-469〕
Fungicides can either be contact, translaminar or systemic. Contact fungicides are not taken up into the plant tissue and protect only the plant where the spray is deposited. Translaminar fungicides redistribute the fungicide from the upper, sprayed leaf surface to the lower, unsprayed surface. Systemic fungicides are taken up and redistributed through the xylem vessels. Few fungicides move to all parts of a plant. Some are locally systemic, and some move upwardly.
Most fungicides that can be bought retail are sold in a liquid form. A very common active ingredient is sulfur,〔C.Michael Hogan. 2011. (''Sulfur''. Encyclopedia of Earth, eds. A.Jorgensen and C.J.Cleveland, National Council for Science and the environment, Washington DC )〕 present at 0.08% in weaker concentrates, and as high as 0.5% for more potent fungicides. Fungicides in powdered form are usually around 90% sulfur and are very toxic. Other active ingredients in fungicides include neem oil, rosemary oil, jojoba oil, the bacterium ''Bacillus subtilis'', and the beneficial fungus ''Ulocladium oudemansii''.
Fungicide residues have been found on food for human consumption, mostly from post-harvest treatments.〔Pesticide Chemistry and Bioscience edited by G.T Brooks and T.R Roberts. 1999. Published by the Royal Society of Chemistry〕 Some fungicides are dangerous to human health, such as vinclozolin, which has now been removed from use.〔Hrelia ''et al.'' 1996 - The genetic and non-genetic toxicity of the fungicide Vinclozolin. Mutagenesis Volume 11 445-453〕 Ziram is also a fungicide that is thought to be toxic to humans if exposed to chronically. A number of fungicides are also used in human health care.
== Natural fungicides ==
Plants and other organisms have chemical defenses that give them an advantage against microorganisms such as fungi. Some of these compounds can be used as fungicides:
*Tea tree oil〔(【引用サイトリンク】url=http://www.webmd.com/vitamins-supplements/ingredientmono-113-TEA+TREE+OIL.aspx?activeIngredientId=113&activeIngredientName=TEA+TREE+OIL&source=2&tabno=2 )〕
Whole live or dead organisms that are efficient at killing or inhibiting fungi can sometimes be used as fungicides:
*Kelp (powdered dried kelp is fed to cattle to help prevent fungal infection)
* ''Ampelomyces quisqualis''
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』