Hello Everyone,

I have found two leaves of Berberis which apparantly have a Diaporthe fungus growing on them. There is no protruding ostiole, unlike with most Diaporthe species.

The spores are 1-septate, 4-guttulate, hyaline and with a small appendage ~ 0.75 um at each end. Also, they appear to be longitudinally striate and measure between 12.5 - 14.5 x 4 um.

The 8-spored ascus tips react blue to lugol.

I have attached photos of the hemispherical fruit bodies contained within a blackened area of an old leaf, which is becoming skeletal. Also two more photos showing fruit bodies within an area demarked by stromatic lines on the upper side of a less decayed leaf. On the underside of this leaf, the demarked area is blackened.

A photo of the appendaged spores is attached, along with an image of asci and spores in lugol, showing the longitudinal striations. The excipulum seems to be brown to reddish brown.

The closest species to mine, which I can find, is Diaporthe scobina, but from the sparse information which I have found, this species seems to grow on wood of Fraxinus and reacts red to lugol at the ascus tip.  

I wonder if anyone has an idea as to which species mine might be?

Thank You,
With Best Wishes,
Peter.