Integrated Approach is Best for Botrytis Blossom Blight
Botrytis blossom blight is an early-season disease impacting southern highbush blueberries. Although not frequently observed causing severe damage in Florida fields most years, infections starting during bloom can later develop into gray mold, which has become an important postharvest disease. The fungal pathogen, Botrytis cinerea, typically infects wounded or senescent floral tissues. As a blueberry bush blooms, white bell-shaped corollas (the fused petal of the flowers) should drop from the flower following pollination but before they senesce (turn brown). However, frost damage can wound plant tissues, delaying petal drop and facilitating infection of the flowers, undeveloped fruit, and damaged twigs and leaves. The pathogen survives in these dead and wounded plant tissues on the blueberry bush and on nearby weedy plants as well. Spores from these sources are abundantly produced when cool, wet periods occur during blueberry bloom through harvest.