Novel Phytophthora and biodiversity impactsHealthy foliage free of Phytophthora © James Williams



Phytophthora is a genus of plant-damaging water moulds that are responsible for a number of notorious plant diseases, such as potato blight.  Three species, named ramorum, kernoviae and pseudosyringae have recently been identified in the UK affecting heathland plants.  They are believed to be non-native, and may have been introduced via international horticultural trade.


Phytophthora ramorum and kernoviae can affect a wide range of native and garden plants.  Findings in the 'wild' in the UK were originally restricted to infections of the non-native invasive species Rhododendron ponticum, however it has now spread to infect bilberry and larch. Larch is commonly planted in forestry and has high direct economic value across the UK. Bilberry is a native species and an important component of many habitats such as heathland. Laboratory testing shows that other native species such as heather, cowberry and bearberry may also be highly susceptible.


Once infections occur, they can spread very rapidly through other susceptible species due to spore production. Larch in particular produces very high numbers of spores which disperse widely due to the height of the trees.  


Damage produced by Phytophthora @ Forestry CommissionFurther Information