Cause The fungus Puccinia vincae has been found in all PNW states. An alternate host is not needed for this autoecious rust. The frequent occurrence of the rust on new leaves and other factors suggest that the rust may be systemic in the plant.
Symptoms Leaves turn chlorotic with inconspicuous leaf spots on the upper surface of the leaf. Lower leaf surfaces have dark uredina where telia are also produced. Heavily infected leaves may curl upward and shoots typically do not flower. Poor winter survival once a bed of plants is infected in western Oregon.
Cultural control
- Remove and destroy infected plants or plant parts.
- Avoid overhead irrigation or apply such that plants are not wet for extended periods of time.
Chemical control
- Pageant at 12 to 18 oz/100 gal water. Do not use with organosilicone-based adjuvants. Group 7 + 11 fungicide. 12-hr reentry.
- Phyton 27 at 1.3 to 2 oz/10 gal water. Group M1 fungicide. 48-hr reentry.
- Terraguard SC at 4 to 8 fl oz/100 gal water. Group 3 fungicide. 12-hr reentry.
Reference Hernández, J.R., Palm-Hernández, M.E. and Tidwell, T. 2002. First report of Puccinia vincae on Vinca spp. in California. Plant Disease 86:75-75.