I agree with Kari’s analysis. Sounds like Marssonina. Bring or send some up if 
you’d like.


Daniel R. Cooley, Professor of Plant Pathology
Stockbridge School of Agriculture                 
418 Paige Lab
161 Holdsworth Way
University of Massachusetts, Amherst, MA 01003                          
Office Phone: 413-577-3803  |  Cell: 413-531-3383 

> On Oct 9, 2018, at 7:52 PM, David Kollas <kollasorchar...@gmail.com> wrote:
> Dan, Brian, Kari, Mo, and others:
>       Having read your comments and links, I looked more closely at my 
> symptoms.  I was wrong about its association with yellow delicious breeding.  
> I can find it in Macoun, Empire, and many others.  The symptom common to all 
> that I looked at with magnifying
> glass was scattered dark blackish raised dots in the live or dead “spot” that 
> often retains its green color after surrounding areas have
> yellowed. I did not find any affected leaves that exhibited the concentric 
> bands noted in the 2012 blog, with click-enlarging photograph, by Dave 
> Rosenberger on Glomerella leaf spot.  Therefore I conclude it is not 
> Glomerella infection.  If it is Marssonina leaf spot, I would
> not expect it to have survived all the captan sprays I have administered. 
> Sooty Blotch and Flyspeck, in spite of all the favorable
> conditions for those diseases, are rare here at this time.  I suppose it 
> could have a physiological cause that made areas of the leaves
> susceptible to opportunist fungi, and some petri dish work in a lab might 
> isolate and identify those raised black dots. It is discouraging
> to loose the leaves before harvest, not knowing why, nor what could have been 
> done to avoid it,
> David Kollas
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