What are the symptoms of botrytis?
Botrytis primarily attacks tender, weak, wounded or dead tissue. Symptoms appear on infected flower petals as restricted lesions. Subsequently, these lesions become necrotic and spread to the whole petals and receptacle, finally resulting in collapse of the flower head and petal drop, causing reduced market value. On leaves, symptoms start as small, water-soaked spots that enlarge and coalesce, so infected leaves appear blighted. When stems are infected, black, sunken and elongated lesions can develop.
On bulbs, outer bulb scales may also be infected and show yellow to brown sunken lesions. Small, shiny, black fungal resting structures (sclerotia) may be visable on the surface of infected bulb tissue. Grey, fluffy mycelium evident on infected plant tissues is a characteristic of identifying Botrytis blight.
Botrytis Life Cycle