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Overview of Plant Disease Diagnoses for 2013

282 samples came from Marion county in 2013. Homeowners submitted various woody and herbaceous ornamentals that had a variety of fungal diseases.

Growers (not glasshouses or nurseries) submitted mostly blackberry, blueberry, boxwood, firs (including Christmas trees), rose, wheat, and ryegrass.  Blackberry problems were mostly abiotic and associated with herbicide injury, nutrient imblance, or low soil pH. Blueberries had Blueberry Shock Ilarvirus, Phytophthora root rot, and abiotic problems associated with low soil pH, mechanical injury, chemical injury and cultural issues. Firs had abiotic water stress issues, neeedle necrosis and needle cast fungi, and dieback associated with Phytophthora root rot. English boxwood had box blight. Roses had downy mildew. Wheat and Ryegrass had BYDV, while wheat had take-all, head blight, and abiotic chemical injury.

Glasshouse growers submitted woody ornamentals. Colletotrichum was associated with cutting rot and anthracnose.  Various fungal rots were associated with Pestalotiopsis, Phytophthora and Thielaviopsis.

Nurseries submitted mostly woody ornamentals, but also blueberry with a similar range of problems to those of the glasshouse growers. In addition, Volutella blight was found on boxwood, and Apple mosaic virus and Prunus necrotic ringspot virus were found in roses.