Phytophthora cinnamomi

Phytophthora cinnamomi is a soil-borne oomycete, a water mould, that causes dieback, root rot and, in some chestnut species, ink disease across an unusually wide range of host plants. It infects economically important crops and ornamentals including avocado, pineapple, azalea, camellia and boxwood, producing wilting, reduced fruit yield, collar rot, gum exudation and stem cankers. Present in more than seventy countries, it is treated as one of the most invasive plant pathogens known and a serious threat to both commercial agriculture and native plant communities.