Apple Mosaic Virus: Keep or discard tree?

General Fruit Growing
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I am 99% sure that I have apple mosaic virus in a second leaf Chestnut crab growing on M7. Leaves yellowed with green spots, no browning at all, falling off mostly near the trunk. Dropping fruit too. We have had a cold, wet spring and just started getting higher temperatures (+80 F).

I am undecided if I should take out the tree and replace with an uninfected tree. On one hand, I think the weather is largely to blame for the manifestation of the disease this year. I know that some varieties are more susceptible than others. Does anyone out there have experience with AMV on a chestnut crab (purchased from Adams County Nursery)? I was hoping to graft some other crabs on in the future (Centennial, Wickson, Bastain’s orange crab, etc.). Anyone with experience with AMV with those apple cultivars? I just do not want to keep this tree if I am going to have to fight a losing battle year after year. Opinions?

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I’m interested in any information on the topic and hope someone comments.

ACN should have a comprehensive program to test for AMV and other virus infections. Grafting material that is 100% clean may not be possible, but I expect ACN would be interested to know if they shipped trees infected with AMV.

I have not seen much discussion about AMV on crab apple rootstocks but G935 and some other rootstocks have big problems with AMV and other latent virus infections.

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I did send an email to ACN regarding my findings. I am awaiting a response.

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I am sure some varieties are more prone to it than others, but I do know it depends on your scion source. I had Ohio Nonpariel that I got from a source last year every graft showed signs of apple mosiac virus amongst a row of misc other varieties. I dug them out and disposed of them. This year I tried a different source for ON and the grafts are just fine.

I would agree that I doubt ACN would knowingly sell any trees infected with AMV as well.

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It must be hard to get certified virus free scion wood for less popular varieties. When I spoke with the ACN salesman during an apple conference he indicated they would not custom bud their Winesap to G935 because of virus concerns.

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Here is a related thread.

The infected tree stopped showing symptoms and is doing great now that the weather has warmed up. I plan to keep mine.

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Thanks Dan. Yes, my leaves look pretty similar to those you posted. I lost most of my fruit on this tree, unfortunately. It is difficult to say if the fruit drop was due to AMV or being a second leaf tree or some other reason (no curc bites that I have noticed). I am not sure how my zone 6 (Pennsylvania) will compare to your 9b (California) with respect to the disease. Hopefully, the awful weather that we had this spring does not repeat itself in the near future!

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