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

Dan


—
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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