Phytophthora mengei (P. citricola) and P. cinnamomi have been associated with trunk canker and collar rot of avocado. The pathogen infects the crown, lower trunk and limbs of older trees. The disease develops after crowns, limbs, or trunks become infected through wounds, such as injuries from equipment, pruning, vertebrate chewing, and wind damage.
The measures recommended for the control of Phytophthora avocado trunk canker disease are similar to those described for Phytophthora root rot. In fruit, prevention of infection is challenging because it is likely caused by the splashing of Phytophthora spores from the soil surface to the fruit during rainy weather.