O-zone Injury on Vegetables
Crystal Stewart-Courtens, Extension Vegetable Specialist
Eastern New York Commercial Horticulture
Hot, humid weather with stagnant air masses may lead to ozone damage on crops. Ozone warnings were recently issued for much of New York. These warnings are intended for people with respiratory problems and let them know they should limit their outdoor activity and try to stay as much as possible in air-conditioned locations. These warning are also a good indicator that ozone damage may occur in plants.
Common ozone symptoms are small, irregular, shaped spots that range in color from dark brown to black (stipple like) or light tan to white (fleck like). These spots are found only on the upper surface of the leaf. Very young and old leaves are less susceptible to ozone while newly mature leaves are the most susceptible. With severe damage, symptoms may extend to the lower leaf surface.
Insect feeding (red spider mite and some leafhoppers) produce flecks on the upper surface of leaves, much like ozone injury. Flecks from insect feeding are usually spread uniformly over the leaf surface while ozone flecks are concentrated in specific areas, usually most pronounced at the leaf tip and along the margins.
The most sensitive crops include: Bean, Broccoli, Muskmelon, Onion, Potato, Radish, Spinach, Sweet Corn, Tomato
Intermediate crops include: Carrot, Endive, Parsley, Parsnip, Turnip
Tolerant crops include: Beet, Cucumber, Lettuce
Upcoming Events
2025 Finger Lakes Auction Winter Growers Meeting
January 2, 2025
Penn Yan, NY
At this grower-focused meeting, ag industry experts will discuss pest control in vegetables, weed management strategies and best practices, seed germination, an introduction to foliar nutrient uptake in vegetables, and grouping flowers by growth needs. Plus we'll hear from a grower panel from Kutztown Produce Auction, moderated with NYS specific pest control from Judson Reid.
2.25 DEC recertification credits will be offered in categories 10, 1a, 23, and 24.
2025 Ontario Produce Auction Winter Growers Meeting
January 15, 2025
Stanley, NY
This grower-focused meeting will include information about pesticide applicator recertification and record keeping requirements, disease control in cole crops and vine crops, and using biocontrols for insect management in greenhouses. Several seed and ag input companies will be on-hand to share product news.
2.75 DEC recertification credits will be offered in categories 10, 1a, 23 and 24. CORE credits (0.5) offered too!
Intro to Food Safety and GAPs Training
February 19, 2025
via Zoom,
This virtual workshop will serve two purposes:
- For produce farms just interested in learning about farm food safety, this program will introduce principles and best practices.
- For produce farms look for a GAPs (Good Agricultural Practices) training needed to meet buyer demands for audit/certification, this program will provide that as well.