It is not a frequent fungal disease, it manifests particularly on some Alba roses, rugosa and perpetual hybrids: it has orange, punctiform pustules on the underside of the leaves, it’s the main cause for a serious weakening of the plant.
The preventive actions are based on copper-based products, therefore by treating against Blackspot, the plant is also protected from this pathogen.
Systemic measures works better for stop the infection, which is very debilitating for the plant. The active ingredients are the same as for the Blackspot: Copper oxychloride, Triazoles, Fosetyl and aluminum. The same precautions can be used in case of rameal cancer (f.asc. Leptosphaeria coniothyrium, f.con. Coniothyrium fuckelii) and for brown cancer of the rose (Cryptosporella umbrina).