Prochlorbria

Prochlorbria is a broad-spectrum fungicide based on prochloraz. It belongs to the same FRAC group as the triazoles but is an imidazole, and in practice that structural difference means it often still performs against populations that have shifted away from triazole sensitivity — particularly in cereal eyespot and Septoria. It is also widely used post-harvest on citrus and tropical fruit.

Characteristics

• —Broad spectrum across cereals, oilseed rape, vine and post-harvest fruit
• —Often effective where triazole sensitivity has declined
• —Strong on cereal eyespot and Septoria
• —Used both in-field and post-harvest
• —FRAC Group 3 — but structurally distinct from the triazoles
• —High 450 g/l loading

How it works

Prochloraz inhibits C14-demethylase and blocks ergosterol synthesis, as the triazoles do — but as an imidazole it binds the enzyme differently, which is why cross-resistance with triazoles is often incomplete. It is still FRAC Group 3, so it does not count as a true rotation partner for resistance management.