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Salvia Go to: Sage (Salvia sp.) ...

Schefflera-Pseudomonas Leaf Spot Cause Pseudomonas cichorii, a bacterium. Warm, humid conditions such as frequent misting favor disease development on schefflera. Older, more mature leaves are more susceptible. The bacterium can survive on a wide range of ...

Schizanthus (Butterfly Flower)-Botrytis Blight See: Greenhouse Plants, Ornamental- Gray Mold Chemical control Best used with cultural controls. Tank-mix and/or alternate products with different modes of action to prevent the buildup of resistant fungi. As ...

Sedum-Root Rot and Stem Rot See: Greenhouse Plants, Ornamental- Pythium Seed Rot, Damping-off, and Root Rot Cause Pythium sp. and Phytophthora sp. have been found several times by the OSU Plant Clinic. These pathogens are favored by water saturated soil c ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Black Leg By C. M. Ocamb Cause Plenodomus lingam (syn. Leptosphaeria maculans, anamorph: Phoma lingam) and Plenodomus biglobosus (syn. Leptosphaeria biglobosa) are fungi that can infect a range of crucifer ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Black Rot Cause Xanthomonas campestris pv. campestris is a bacterium that overwinters in plant refuse for up to 2 years and is carried internally and externally on seed. The bacterium infects other crucife ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Alternaria Diseases (Black Spot, Gray Leaf Spot, Pod Spot) By C. M. Ocamb Cause Alternaria brassicae and A. brassicicola can infect leaves, petioles, stems, flower parts, and seed pods of a wide range of B ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Cladosporium Leaf Spot Cause A fungus, Cladosporium variable. This fungus can grow under a wide range of temperatures, but 59°F to 68°F with relative humidity above 80% is most conducive to disease develop ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Downy Mildew (Staghead) By C. M. Ocamb Cause Peronospora parasitica (= Hyaloperonospora parasitica), a fungus-like microorganism that overwinters in roots or on leaves or stems of infected, living plants. ...

Seed Crop, Crucifers (Brassica and Raphanus spp.)-Chlorotic Leaf Spot (Light Leaf Spot) By C. M. Ocamb Cause The fungus, Cylindrosporium concentricum (sexual stage: Pyrenopeziza brassicae) was found in Oregon on canola, turnip, volunteer or wild radish, w ...