what is this and can we fix it, need help

[Duster]

My In-laws recently moved to North Carolina from Indiana (Happy Retirement). Anyway, on there property is several vines that I believe to be Catawba but I'm not certain. Earlier this spring my wife and I helped them move and while we were there I trimmed the vines back for them, this is something that obviously haven't been done in a few years. They has been keeping me posted on the status of the vines as the summer progresses. I received an E-mail from them today with bitter sweet news, I am informed that the vines have lots of grapes on them but they have brown spots all over them and I was asked what can be done. My answer was simple, I have no clue but I know where to get the answer! This leads me to this post, Please see the pics and see if we can figure this thing out.
Thanks in advance for the help.

 

[Julie]

Since they are in North Carolina, I wonder if it is not a muscadine grape. I am not by any means an expert but I wonder if the brown spots is from a lack of water?

 

[Sammyk]

Duster where are they in NC?
WE have had plenty of rain, Julie. After 3 years of drought, there is no drought anywhere in NC. As a matter of fact we are on the plus side of rain for this year.

 

[Deezil]

I could be wrong (Read: Wait for grapeman) but it looks like Black Mold to me

Referencing this page, in relation to the picture in-focus, I think thats a shirt/tummy? 3rd picture..

"Fruit: Shortly after the flower petals fall, fruit infection can occur. Most infections start when the fruit is half to almost full size. A small spot will appear that becomes circular and whitish tan, often surrounded by a brown ring. This happens while the berry is still green. The spots grow rapidly and may cover half of the berry within 48 hours. Within a few days the entire berry becomes coal black, hard, and mummified. The surface of the withered fruit is soon covered with minute, black, pimple-like, sporeproducing pycnidia that are arranged in circular zones."


And then from this doc:

"Disease Cycle: The fungus overwinters in mummified
berries on the soil or in old berry clusters that hang in
the vines. Spores of the fungus are produced within the
diseased fruit and infect leaves, blossoms, and young fruit
during spring rains. Fruit infections occur from mid-bloom
until the berries begin to color. Mature leaves and ripe
fruit are not susceptible. Very few berries or leaves are
infected after late July, and none are infected after the end
of August. Black rot infections depend on the temperature
and the length of time the leaves are wet.


Disease Management:
Infected prunings and mummified
berries should be removed and disked into the soil before
new growth begins. In vineyards with susceptible cultivars
or where black rot was a problem the previous year, early
season fungicide sprays should be timed to prevent the
earliest infections. Should infections become numerous,
protecting against fruit rot later in the growing season will
be difficult. It is strongly suggested that resistant cultivars
be planted."

 

[Duster]

Since they are in North Carolina, I wonder if it is not a muscadine grape. I am not by any means an expert but I wonder if the brown spots is from a lack of water?

I would love for them to be Muscadine, I hope your right.
They are located in Murphy, extreme south west NC.
wow, considering there on the east coast, this can really get confusing and theres no wonder it's often referred to as the middle of nowhere!

 

[Duster]

I could be wrong (Read: Wait for grapeman) but it looks like Black Mold to me

Referencing this page, in relation to the picture in-focus, I think thats a shirt/tummy? 3rd picture..

"Fruit: Shortly after the flower petals fall, fruit infection can occur. Most infections start when the fruit is half to almost full size. A small spot will appear that becomes circular and whitish tan, often surrounded by a brown ring. This happens while the berry is still green. The spots grow rapidly and may cover half of the berry within 48 hours. Within a few days the entire berry becomes coal black, hard, and mummified. The surface of the withered fruit is soon covered with minute, black, pimple-like, sporeproducing pycnidia that are arranged in circular zones."


And then from this doc:

"Disease Cycle: The fungus overwinters in mummified
berries on the soil or in old berry clusters that hang in
the vines. Spores of the fungus are produced within the
diseased fruit and infect leaves, blossoms, and young fruit
during spring rains. Fruit infections occur from mid-bloom
until the berries begin to color. Mature leaves and ripe
fruit are not susceptible. Very few berries or leaves are
infected after late July, and none are infected after the end
of August. Black rot infections depend on the temperature
and the length of time the leaves are wet.


Disease Management:
Infected prunings and mummified
berries should be removed and disked into the soil before
new growth begins. In vineyards with susceptible cultivars
or where black rot was a problem the previous year, early
season fungicide sprays should be timed to prevent the
earliest infections. Should infections become numerous,
protecting against fruit rot later in the growing season will
be difficult. It is strongly suggested that resistant cultivars
be planted."

Thanks Deezil, you may be onto something, I wonder what others may think as well.

 

[grapeman]

It may be a bad case of anthracnose which gives brown spots with a dark center giving the appearance of an eye. Normally you only get one lesion per berry but in severe cases you can get numerous ones like you have. Regardless of which it is you need a spray program to PREVENT it. It is probably too late for this year. It is normally worse on uncared for vines (or recently pruned as is your case) because the disease builds up in the old wood.

 

[Duster]

It may be a bad case of anthracnose which gives brown spots with a dark center giving the appearance of an eye. Normally you only get one lesion per berry but in severe cases you can get numerous ones like you have. Regardless of which it is you need a spray program to PREVENT it. It is probably too late for this year. It is normally worse on uncared for vines (or recently pruned as is your case) because the disease builds up in the old wood.

Thanks Grapeman. Do you think Deezil may be onto something with the black mold or black rot?
If it is anthracnose do you have a recomendation for a spray?

 

[grapeman]

Mancozeb, manzate or dithane work on both black rot and anthracnose to some degree, but at this stage, it is too late for this year to control it. They are all preventative, not curative. If it was black rot, the whole berries would be affected and shrivel to mummies. Anthracnose gives the "birdseye" appearance I see on those lesions although they are generally better defines. It may be black rot also. It is always hard to tell for sure with just a couple pictures and not a specimen at hand, especially with my eyes anymore.

 

[lawrstin]

I would agree with grape man that this is birds eye (anthracnose). It would be nice to see some pictures of the leaves too. I would remove the clusters and properly dispose of them. In addition, I suggest trying to open your canopy up by toping, trimming and leaf pulling. I would also use a fungicide spray every two to four weeks after bud break, I like to hold off as late as possible.