QoI
Encyclopedia
Qo inhibitors or Quinone outside inhibitors are a group of fungicide
s used in agriculture
. They represent the most important development made in fungicides by the chemicals industry. QoI are chemical compounds which act at the Quinol outer binding site of the cytochrome bc1 complex.
QoI's are the resulting fusion of three fungicides families, the well-known family of strobilurin
s and two new families, represented by fenamidone and famoxadone. Some strobilurins are azoxystrobin, kresoxim-methyl, picoxystrobin, pyraclostrobin and trifloxystrobin.
These fungicides are used on a wide range of crops, such as cereals, vines, pome fruits, cucurbits, tomatoes and potatoes.
For example, they are used as fungicides for cereals, against Erysiphe graminis f.sp tritici responsible for the powdery mildew
in wheat
or against Septoria tritici
, responsible for septoria leaf spot
in wheat.
They are also commonly used for vine
culture, against Plasmopara viticola
, responsible for downy mildew
or in oïdium treatment.
All these fungicides are in the same cross-resistance group (same mode of action) and must be managed carefully to avoid the appearance of fungicide
resistance. Some fungicide resistance has been observed in most crops (such as in the case of wheat powdery mildew
), so the application of QoI products should respect effective rates and intervals to provides time and space when the pathogen
population is not influenced by the product selection pressure.
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or 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...
s used in agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...
. They represent the most important development made in fungicides by the chemicals industry. QoI are chemical compounds which act at the Quinol outer binding site of the cytochrome bc1 complex.
QoI's are the resulting fusion of three fungicides families, the well-known family of strobilurin
Strobilurin
Strobilurins are a group of chemical compounds used in agriculture as fungicides. They are part of the larger group of QoI inhibitors, which act to inhibit the respiratory chain at the level of Complex III....
s and two new families, represented by fenamidone and famoxadone. Some strobilurins are azoxystrobin, kresoxim-methyl, picoxystrobin, pyraclostrobin and trifloxystrobin.
These fungicides are used on a wide range of crops, such as cereals, vines, pome fruits, cucurbits, tomatoes and potatoes.
For example, they are used as fungicides for cereals, against Erysiphe graminis f.sp tritici responsible for the powdery mildew
Wheat mildew
Wheat mildew is a wheat disease that affects the ear, and is brought on by causes somewhat similar to those that cause blight, though at a more advanced period of the season. If this disorder comes on immediately after the first appearance of the ear, the straw is also affected—but if the...
in wheat
Wheat
Wheat is a cereal grain, originally from the Levant region of the Near East, but now cultivated worldwide. In 2007 world production of wheat was 607 million tons, making it the third most-produced cereal after maize and rice...
or against Septoria tritici
Septoria tritici
Septoria tritici is the causal agent of S. tritici leaf blotch, a foliar disease of wheat, and occasionally infects other grasses including barley...
, responsible for septoria leaf spot
Septoria
Septoria are Ascomycete fungi that causes numerous leaf spot diseases on field crops, forages and many vegetables, and is responsible for yield losses...
in wheat.
They are also commonly used for vine
Grape
A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...
culture, against Plasmopara viticola
Plasmopara viticola
Plasmopara viticola, the causal agent of grapevine downy mildew, is a heterothallic oomycete that overwinters as oospores in leaf litter and soil. In the spring, oospores germinate to produce macrosporangia, which under wet conditions release zoospores. Zoospores are splashed by rain into the...
, responsible for downy mildew
Downy mildew
Downy mildew refers to any of several types of oomycete microbes that are obligate parasites of plants. Downy mildews exclusively belong to Peronosporaceae. In commercial agriculture, they are a particular problem for growers of crucifers, grapes and vegetables that grow on vines...
or in oïdium treatment.
All these fungicides are in the same cross-resistance group (same mode of action) and must be managed carefully to avoid the appearance of fungicide
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or 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...
resistance. Some fungicide resistance has been observed in most crops (such as in the case of wheat powdery mildew
Mildew
Mildew refers to certain kinds of molds or fungi.In Old English, it meant honeydew , and later came to mean mildew in the modern sense of mold or fungus....
), so the application of QoI products should respect effective rates and intervals to provides time and space when the pathogen
Pathogen
A pathogen gignomai "I give birth to") or infectious agent — colloquially, a germ — is a microbe or microorganism such as a virus, bacterium, prion, or fungus that causes disease in its animal or plant host...
population is not influenced by the product selection pressure.
External links
- Fungicides Resistance Action Committee, QoI Includes information on QoI working groupWorking groupA working group is an interdisciplinary collaboration of researchers working on new research activities that would be difficult to develop under traditional funding mechanisms . The lifespan of the WG can last anywhere between a few months and several years...
activities. - Gray Leaf Spot Resistance to Strobulurins