Fluazinam is a broad-spectrum fungicide used in agriculture. It is classed as a diarylamine and more specifically an arylaminopyridine. Its chemical name is 3-chloro-''N''-(3-chloro-2,6-dinitro-4-trifluoromethylphenyl)-5-trifluoromethyl-2-pyridinamine. The mode of action involves the compound being an extremely potent

uncoupler An uncoupler or uncoupling agent is a molecule that disrupts oxidative phosphorylation in prokaryotes and mitochondria or photophosphorylation in chloroplasts and cyanobacteria by dissociating the reactions of ATP synthesis from the electron trans ...

oxidative phosphorylation Oxidative phosphorylation (UK , US ) or electron transport-linked phosphorylation or terminal oxidation is the metabolic pathway in which cells use enzymes to oxidize nutrients, thereby releasing chemical energy in order to produce adenosine t ...

in mitochondria and also having high reactivity with

thiols In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl grou ...

. It is unique amongst uncouplers in displaying broad-spectrum activity against fungi and also very low toxicity to mammals due to it being rapidly metabolised to a compound without uncoupling activity. It was first described in 1992 and was developed by researchers at the Japanese company Ishihara Sangyo Kaisha.

Uses

Fluazinam is a protectant fungicide, but is neither systemic or curative. It acts by inhibiting the germination of spores and the development of infection structures. Although it has activity against many fungi, it is less potent against

rusts Rust is an iron oxide, a usually reddish-brown oxide formed by the reaction of iron and oxygen in the catalytic presence of water or air moisture. Rust consists of hydrous iron(III) oxides (Fe2O3·nH2O) and iron(III) oxide-hydroxide (Fe ...

and

powdery mildew Powdery mildew is a fungal disease that affects a wide range of plants. Powdery mildew diseases are caused by many different species of ascomycete fungi in the order Erysiphales. Powdery mildew is one of the easier plant diseases to identify, as ...

and as such has not been commercialised for use in cereal crops. It is widely used to control

late blight ''Phytophthora infestans'' is an oomycete or water mold, a fungus-like microorganism that causes the serious potato and tomato disease known as late blight or potato blight. Early blight, caused by '' Alternaria solani'', is also often called " ...

(''P. infestans'') in

potato The potato is a starchy food, a tuber of the plant ''Solanum tuberosum'' and is a root vegetable native to the Americas. The plant is a perennial in the nightshade family Solanaceae. Wild potato species can be found from the southern Un ...

due to its activity against the

zoospores A zoospore is a motile asexual spore that uses a flagellum for locomotion. Also called a swarm spore, these spores are created by some protists, bacteria, and fungi to propagate themselves. Diversity Flagella types Zoospores may possess one or ...

of the pathogen which makes it particularly effective at controlling infection of the potato tubers. Because of its extensive usage to control late blight in Europe, there are confirmed reports of resistance to fluazinam appearing in ''P. infestans'' in genotypes EU_33_A2 and EU_37_A2. Fluazinam is also used to control ''

Sclerotinia ''Sclerotinia'' is a genus of fungi A fungus (plural, : fungi or funguses) is any member of the group of Eukaryote, eukaryotic organisms that includes microorganisms such as yeasts and Mold (fungus), molds, as well as the more familiar mu ...

'' on peanuts and turf, ''

Botrytis Botrytis may refer to: * ''Botrytis'' (fungus), the anamorphs of fungi of the genus ''Botryotinia'' **''Botrytis cinerea'', a mold important in wine making *Botrytis, the cauliflower cultivar group of ''Brassica oleracea ''Brassica oleracea'' is ...

'' on grapes and beans and

clubroot Clubroot is a common disease of cabbages, broccoli, cauliflower, Brussels sprouts, radishes, turnips, stocks, wallflowers and other plants of the family Brassicaceae (Cruciferae). It is caused by ''Plasmodiophora brassicae'', which was once cons ...

brassicas ''Brassica'' () is a genus of plants in the cabbage and mustard family (Brassicaceae). The members of the genus are informally known as cruciferous vegetables, cabbages, or mustard plants. Crops from this genus are sometimes called ''cole c ...

Toxicity

The acute oral

median lethal dose In toxicology, the median lethal dose, LD50 (abbreviation for "lethal dose, 50%"), LC50 (lethal concentration, 50%) or LCt50 is a toxic unit that measures the lethal dose of a toxin, radiation, or pathogen. The value of LD50 for a substance is ...

in rats is very low at over 5000 mg/kg due to the compound's reactivity with thiols. This reactivity can have negative consequences since repeated exposure can cause skin sensitization and dermatitis to develop in some individuals. Fluazinam also displays low toxicity to birds, bees and worms, but has a high toxicity to fish. The toxicity towards fish is considered to be relatively unimportant, since the compound has a very short

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...

(around 1 day) in aquatic systems.

References

{{reflist Fungicides Nitro compounds Trifluoromethyl compounds Aminopyridines Anilines