Phytophthora ramorum - The Food and Environment Research ...

Syringa (Lilac) leaf & bud blight
Lilac leaf necrosis
Leaf symptoms are very similar to
those described for Camellia, Kalmia
and Leucothoe, with leaf necrosis
starting at the tips and margins.
Greyish-brown diffuse, water soaked
lesions become evident later. Bud
blight leads to a brown to black shoot
discoloration as the infection spreads.
Other, similar appearing, diseases of
Syringa include the well known
bacterial shoot, stem and leaf blight
P. syringae, although P. ramorum
primarily affects the leaves of lilac
rather than leaves and shoots.
Taxus baccata (Yew) leaf blight
Yew leaf blight (next to a healthy stem)
Leaf blight caused by P. ramorum is
uncommon but has been isolated
from brown lesions on young leaves
of container grown T. baccata. Yew is
very prone to leaf bronzing, due to a
wide range of diseases and disorders,
but usually the leaf tips die first, whilst
with P. ramorum, the necrosis occurs
more commonly in the leaf axils and
appears more water soaked.
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