Common management practices for these diseases include selecting resistant varieties when available. Long periods of leaf wetness or high humidity promote development of most foliar diseases powdery mildew being a notable exception. If you grow winter greens, regardless of whether or not you have seen any of these diseases, please help by completing the survey.Įarly morning is the best time to look for symptoms because foliar pathogens produce spores during nighttime seeing spores confirms a diagnosis. This information is needed to help determine initial sources of inoculum and potential for pathogen survival between crops and spread. Knowledge about disease occurrence is important for developing appropriate, effective management programs.

This perception is based on reports received so far from growers. Occurrence of these foliar diseases appears to be sporadic, reflecting where the pathogen is present and conditions are favorable. Plastic covering high tunnels protects the pathogens from exposure to damaging UV radiation. Low light levels and short days mean these pathogens have long periods to produce spores. Prolonged periods of leaf wetness or high humidity likely is a factor. Conditions during production of winter greens evidently are very favorable for these pathogens that tolerate cool temperatures. Their occurrence in field-grown plants in late fall and in winter tunnels is perplexing because most have not been observed recently in these crops grown during traditional production periods, with the exception of brassica downy mildew. Plants are susceptible at all stages, including cotyledon stage. All are capable of rendering a crop unmarketable. They include downy mildews (spinach, brassicas and lettuce) and powdery mildews (brassicas and lettuce). Presentation on Organic Disease Control in Winter Tunnels at New England Vegetable and Fruit Conference Dec 2019įoliar diseases observed recently in winter greens are of special concern.What Works for Organic Disease Control in Winter Tunnels.Summary information from survey responses received in 2018.If you grow winter greens please complete this survey.

Downy mildew and powdery mildew of arugula.

Powdery Mildew of Kale, other Brassicas, and Lettuce.

Downy Mildew of Spinach | Lettuce | Kale and other Brassicas.

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