Gray Mold
Gray mold or Botrytis blight can be a very common disease on several different plants in the vegetable and flower garden or greenhouse. Under favorable conditions of high moisture and cool temperatures, the Botrytis fungus produces massive quantities of tiny gray spores, which are readily blown or splashed onto healthy foliage. If a film of moisture is present and other conditions are favorable, germination and infection can take place in a few hours.
Botrytis is sometimes confused with old age and thrip damage. Botrytis blight can infect any plant part. The pathogen can cause collapse and damping-off of seedlings, blossom blight, fruit rot, stem or crown rots, or shoot blight. The fungus normally establishes itself on stressed, aging, dead or inactive tissues.
The disease often over-winters on infected dead plant material. Sanitation is important. Dead head dying flowers and remove all infected plant tissue. Burning is the desired method of destroying infected tissue.
The first symptom is typically a water-soaked spot which later collapses. If the humidity remains high, a grayish-brown fuzzy coating of fungus growth develops on the diseased tissues.
Small (up to 1/4") black, hardened resting structures of the fungus called sclerotia may be produced on fleshy parts of stems or fruits. Often embedded in decayed tissue, these enable the fungus to survive when conditions are not favorable for growth.
The disease often over-winters on infected dead plant material. Sanitation is important. Dead head dying flowers and remove all infected plant tissue. Burning is the desired method of destroying infected tissue.
Control of Gray Mold:
As always, it is a good idea to ask our local County Extension Agent or local Master Gardener for advice. They are always willing to help with regional specific information. Keys to controlling Gray Mold include allowing plants to dry out during the day time, Allow good air flow and circulation , good ventilation in greenhouses, and keeping your plants maintained. |