Dothiorella canker—Botryosphaeria and Fusicoccum spp.
Dothiorella cankers exude reddish sap that dries to a brown and white powder. Bark may be cracked, discolored, or sunken. Under the canker, inner bark and wood is brown, orangish, or red. Small branches and leaves can be killed, leaving entirely brown dry leaves attached to dead limbs. Dead branches may retain fruit, which blackens and shrivels. Fruit infection is not often obvious until it is picked and starts to soften. Initial lesions are small, irregular brown to reddish discolorations on the peel. Brown streaks may occur in the flesh. As fruit ages, the surface lesions become sunken and black, and decay spreads throughout the entire fruit.
Identification | Life cycle
Solutions
Dothiorella canker is usually of minor importance in established, older trees. Where it is a problem, use good sanitation and optimal cultural practices to control it. Prune out dead limbs and twigs during dry conditions. Dispose of dead wood and old fruit away from avocado trees. Knock down groups of dead leaves stuck in trees. Provide sufficient irrigation, and consider planting rootstock cultivars that have some resistance to this disease. | 
Brown dry leaves attached to dead limbs
Reddish sap and white powder |
Black and shriveled fruit |
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