QoI

Qo inhibitors (QoI), or quinone outside inhibitors, are a group of fungicides 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 "bc"1 complex.
QoI's are the resulting fusion of three fungicides families, the well-known family of strobilurins and two new families, represented by fenamidone and famoxadone. Some strobilurins are azoxystrobin, kresoxim-methyl, picoxystrobin, pyraclostrobin, and trifloxystrobin.
Usage.
QoI 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.
Resistance.
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 many crops (such as in the case of wheat powdery mildew), 