How to Manage Pests

UC Pest Management Guidelines

SYMPTOMS

Development of Botrytis limb blight, also referred to as Botrytis dieback, begins when the fungus enters overwintering fruit and tips of shoots that have been damaged by frost. After invading fruit, the pathogen then moves into the shoots and causes cankers above and below the infected fruit, resulting in shoot dieback. The fungus can also infect through fruit or leaf scars, causing defined shoot cankers. In late winter and early spring, abundant buff-colored spores develop on the infected shoots, on blighted fruits and on cankers. In addition, if cool, wet weather prevails in spring, the pathogen infects young developing shoots, causing shoot blight. Foliage of blighted shoots wilts, becomes light green, and then eventually turns brown. Often several blighted shoots can be found per tree in spring.

COMMENTS ON THE DISEASE

Wet and cool springs favor disease development. The spores of Botrytis that develop on the surface of infected fruits and shoots are easily disseminated by air. Botrytis shoot blight is more common on caprifig trees than other fig cultivars because caprifigs bear fruit that is often damaged by frost in spring. Spores of B. cinerea contaminate the healthy mamme caprifig crop and result in significant damage when mamme fruit are stored at 50°F.

MANAGEMENT

Prune infected shoots below the cankered area to remove source of inoculum.

PUBLICATION

UC IPM Pest Management Guidelines: Fig
UC ANR Publication 3447
Diseases
T. J. Michailides, Plant Pathology, Kearney Agricultural Center, Parlier
L. Ferguson, Pomology, Kearney Agricultural Center, Parlier

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