Fungus, Disease or Deficiency???

[Heather_0651]

I’m not quite sure what’s going on? We try to be more natural and not use chemicals so we have not sprayed anything but lavender, tea tree and lemongrass for bugs twice this year. I noticed in my garden my green bean leaves are doing the same thing. It only seems to be on a few leaves out of 200 grapevines. So not all of the plants are doing this. We are in North Texas with lots of rain this year. Zone 8. I’ve tried contacting A&M plant pathology no answer and I’m waiting on a phone call from the Tarleton Horticulture Dept too.

 

[srcorndog]

You will have to spray chemicals because you have then classic diseases of grapes.
1. Phomopsis early infection can lead to fruit rot
2. Anthracnose lesions tend to congregate around main veins unlike phomopsis
3. Black Rot small black (pycnidia) are fruiting bodies that release spores.
Good luck trying to organic garden grapes
To confirm send a leaf sample to your county extension agent

 

[GreginND]

Yes, fungus, fungus, fungus. At this point it is probably too late. Spraying should be started well before any signs of fungal problems show up. But, you can try to keep it in check with some spraying now in hopes that it won't be as bad next year.

 

[TikiWine]

Any thoughts on what this might be. I have narrowed it down to a few possibilities. Also what's the best course of action. These are muscadines

 

[Masbustelo]

Most of us can't identify these diseases very well, because we use various sprays and have never had these problems.

 

[BigH]

Any thoughts on what this might be.

Your last pic looks like downy mildew to me. The second pic in your original post looks like the onset of black rot. Disclaimer, I have no particular skill when it comes to disease identification. If I am right, then your grapes will likely turn to fuzzy black mummies on vines that exhibited black rot.

H

 

[TikiWine]

Thanks big H I am going to try a wide spectrum fungicide. Or since the cluster haven't formed yet is it too late? These aren't my vines just started looking after them didn't know what to expect.

 

[BigH]

Thanks big H I am going to try a wide spectrum fungicide. Or since the cluster haven't formed yet is it too late?

It is worth a shot. I have read posts in the past that would say it is too late to start spraying for black rot once you see it on the leaves. I don't have enough experience to say either way. I don't think the news is quite as gloomy for downy mildew. I would spray if I were in your shoes. If nothing else, you can prevent it from showing up on healthy vines.

H

 

[BigH]

I’m not quite sure what’s going on? We try to be more natural and not use chemicals so we have not sprayed anything but lavender, tea tree and lemongrass for bugs twice this year.

Unfortunately, the Fungi kingdom rules the "all natural" world. Think about it, every insect that can be a pest has some predator that is on your side. Weeds can be eaten by goats or out-competed by other plants . But the Fungi sit pretty much at the top of the food chain. Organic grapes are tough to pull off in most of the country.

H