Rose Rust
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Rose Rust  Spores of rose rust, a fungal disease, overwinter on fallen leaves. They germinate in spring reinfecting bushes through wind and rain splash. Spores also survive on the soil surface, plant stems, fences, stakes, and plant debris.SYMPTOMS: In early spring powdery pustules of light orange to yellow spores appear on the under side of leaves. Soon after these aecieospores can be found on the upper side of leaves where they are more obvious. As we move into summer the uredial stage usually is predominate forming the typical red brown to orange spores. This stage can repeat several times during the growing season usually in 10 to 14 day intervals. Finally as fall approaches and evenings become cool the over wintering telial stage develops black teliospores. Leaves, succulent canes and flower parts are all susceptible to the rose rust fungus. SUSCEPTIBLE PLANTS- Roses
DISEASE CYCLE: The fungus over winters as teliospores on fallen leaves or on infected canes. The spores are wind borne and germinate to infect leaves through the stomata.Rose rust fungi are obligate parasites and can not be cultured. As the infection proceeds the various
Reinfection and spread occurs through aeciospores and urediospores. PREVENTION AND CONTROL: In areas where rose rust is severe, sanitation should be practiced to reduce inoculum and prevent early season infections. Infected canes should also be spring pruned to reduce the initial inoculum levels. Pruning very dense bushes will help to reduce the moisture levels inside of plants and prevent some infections. Fungicidal Controls- The most effective fungicidal products are copper or sulfur based. Fungicidal sprays, soaps or dusts such as a Copper Fungicide
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