- Shoot dieback
- Caused by multiple species of fungi
Symptoms usually start on the current year's growth, often at the site of a pruning wound. Symptoms vary but include shoot blights that cause flagging, wilting, dieback and death of branches and/or sunken cankers. Key signs include oozing ribbons of spores (called cirrhi) out of black fruiting bodies.
These pathogens often infect plants suffering from other stresses, like drought, root problems, or excess fertilizer. Phoma or phomopsis blight is caused by multiple species in the genus Phomopsis. Confusion arises because the sexual state of the fungus is often Diaporthe spp.
Prune out and dispose of infected branches. As this is an opportunistic pathogen, the underlying disorder must be addressed to remedy this secondary problem. Few fungicides are effective against Phomopsis.
Pesticides are neither available nor recommended for managing this disease.
