Fungi

Clubroot caused by Plasmodiophora brassicae is a major disease of brassica, i.e., broccoli, cabbage, turnip, rutabaga, and radish. It can also infect weeds in the mustard family as well as some grasses.

Corky root is caused by the fungus Pyrenochaeta lycopersici. Tomato plants affected with corky root may appear stunted and generally lack vigor.

Black dot root rot found in high tunnel tomatoes

Southern Blight Problem in Peppers

2023 Maryland Soybean Fungicide Trial results

Agronomy Newsletter -June 2024, Volume 15, Issue 3. Topics include: State Court of Appeals Overturns Circuit Court’s Right-to-Farm Decision, Thoughts on Tar Spot Management, Scouting for Fusarium Head Blight, Paraquat Training Opportunities, June IPM Insect Scouting Tips, UMD Faculty Member Partners Nationally to Release Highly Anticipated Decision Aid Tool to Produce Maximum Crop Yield, New Forage Enterprise Budgets, Fungicide Efficacy Tables for Corn and Soybean, Weather Outlook, and Maryland Regional Crop Reports.

A County agent sent pictures of squash that were turning yellow and wilting (fig. 1). This was found to be Fusarium crown rot caused by the fungus Fusarium solani f. sp. cucurbitae with a little Anthracnose caused by Colletotrichum orbiculare mixed in with it. In the field, Fusarium crown rot is generally a problem in summer and winter squash, and some pumpkin cultivars, but most cucurbits have been found to be susceptible.

Tar spot is a disease of corn caused by the fungus Phyllachora maydis.

Botrytis in High Tunnel Tomatoes

Agronomy Newsletter -May 2024, Volume 15, Issue 2. Topics include: