The Plant Diagnostic Clinic at the University of Delaware accepts plant samples showing signs or symptoms of disease. The Clinic is housed in the Department of Plant and Soil Sciences at the University of Delaware in Newark , and operates as a function of Delaware Cooperative Extension.

Please Report Downy Mildew on Basil Downy mildew of basil is a serious new disease in the U.S, caused by the fungus-like Oomycete, Peronospora.   Originally found in Uganda and then Europe, basil downy mildew was detected in Florida in 2007 and the northeast U.S. in 2008.  The pathogen was reported in both field and greenhouse grown basil. The most noticeable symptom on affected plants was yellowing in between the veins, and it was thought to be a nutritional problem.   Upon close examination, grayish sporulation of the downy mildew pathogen occurs on the undersides of the leaves. Basil downy mildew spores are produced in abundance and can be spread on by air currents, as well as on infected leaf material and seeds. This disease has not been reported in Delaware, but has been reported in PA, NJ, NY,NC, and other Eastern states.  For this reason, the University of Delaware is joining other universities in a monitoring program.  If you see what you think is basil downy mildew, please send a sample to the UD Plant Diagnostic Clinic.  Please refer to the left menu for sample guidelines, submission forms, and contact information. Thank you! Basil Downy Mildew Upper Leaf Surface - courtesy of M. McGrath, Cornell University   Basil Downy Mildew Lower Leaf Surface - courtesy of M. McGrath, Cornell University   Soybean Rust- 2008 Update USDA ipmPIPE Site Photos of Soybean Rust Get Ready for Spring with Plant Disease Info General Plant Disease Fact Sheets Review the Sample Submission Guidelines Sample Submission Guidelines Sample Submission Form can be Printed From the Left Menu    2008 Delaware Plant Pathology Results and Reports Bulletin 2007 Delaware Plant Pathology Results and Reports Bulletin