Plant Fungal Diseases

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

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.

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.

2023 Maryland Soybean Fungicide Trial results

Southern Blight Problem in Peppers

Black dot root rot found in high tunnel tomatoes

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

Usually when anyone talks about basil problems they talk about basil downy mildew, but there are unfortunately other disease problems with basil that are important and need to be managed.

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

I visited a few tomato fields this week and found 2-4-week-old tomato plants with some early blight (Alternaria solani) and in some cases bad early blight lesions. This is very early in the season to be seeing this level of early blight. Many of the plants had a few flea beetle adults on the plant (fig 1) and in the areas where the early blight was found also had moderate to high flea beetle feeding (fig 2).