Excerpts from NC State Plant Pathology’s June 22, 2018 biweekly vegetable production conference call: Veggie Calls:
- Powdery Mildew has been reported on zucchini in three counties from Western and Central North Carolina.
- Cucumbers in Western North Carolina are exhibiting symptoms of chemical burn. The plants were sprayed with Quadris and Manzate on a hot and humid day at 10 am. However, the new growth appears to be fine and is growing out of it.
- Powdery Mildew is caused by the fungal pathogens Podosphaera xanthii and Erysiphe cichoracearum. Disease can occur on all cucurbit crops. However, due to the incorporation of resistance genes, most commercial cucumber and melon cultivars are less susceptible. High-humidity (50-90%), moderate temperatures (68 to 80 ℉), dense foliage, and low light conditions favor disease development. However, dry conditions favor colonization, sporulation, and dispersal of the pathogen.
