Controlling powdery mildew and rust in roses
Albert O. Paulus
California Agriculture 42(4):15-15. DOI: 10.3733/ca.v042n04p15.
Abstract Not Available – First paragraph follows:
Powdery mildew is undoubtedly the most widespread disease of roses. The causal fungus, Sphaerotheca pannosa var. rosae, appears as a white or gray powdery or mealy coating on the leaves, tender stems, and flower buds. It distorts and discolors those areas, causes defoliation, and reduces plant vigor.