Latent viruses in garlic

[bower]

Just wondering if anyone has had trouble with latent virus, showing up in garlic after a bad summer?

We had late frosts, cold wet July and now two weeks of heat in August, and today I went to pull the earlier porcelains and found that all my Chesnok Red plants have yellow streaks on all their leaves that look like pictures of yellow dwarf or mosaic virus.. I decided to pull them and OMG the bulbs are as small as my thumb. These came from regular sized bulbs I grew last year from a bulb of seed I bought, and seemed healthy and for sure normal size. The Music planted next to them in the same bed have no spots on the leaves and the bulbs although smaller than hoped for are more or less normal I guess for the bad time they had...(worst weather on record).

One row of another variety next to the Chesnok also had affected leaves and there are leaf hoppers around and whatnot, so I pulled everything that looks infected and bagged it foliage and all for the moment till I figure out how to dispose of it. Then I also noticed that some of the rounds I harvested today also have streaky looking leaves and may have been infected by insect spread?... or maybe they also had something latent, that became symptomatic just in the past few days but didn't affect their growth or size, unlike the parent seed... This has been a pesty year and there are various leaf miners and others that could affect garlic or other alliums and maybe look like virus but is not? Wishful thinking maybe. Yes I am confused.

What would you do? Cull everything with any sign of a yellow streak on the leaf? I don't want to lose my rounds for seed stock if there's any way to salvage. If I cut the leaves off before they cure would that help, possibly? Does it matter if a latent virus is there, should I just accept that these plants may go down hard when they're stressed?

[Father'sDaughter]

What a nightmare! Have no experience with this type of thing, so unfortunately (or should I say fortunately) I have no advice.

After recently reading about the garlic bloat nematode showing up in nearby states, I've been leery about buying any new seed stock and my biggest fear is loosing my own seed stock.

I hope you can figure out what it is, and keeping my fingers crossed for you that it turns out to be something benign.

[Father'sDaughter]

Have you read through this document? It might give you some more possibilities.

http://www.gourmetgarlicgardens.com/...es--pests.html

I had been told by the farmer I first bought my seed stock from to soak the cloves in water (he said to add baking soda) and then give them a dunking in alcohol before planting. I still follow his advice, but I had forgotten the details of why it should be done!

[bower]

Thanks, Father'sDaughter, that's a great link... You can't beat simple, straightforward treatments that a grower has used and found helpful and not harmful. Reading about this is making me really mindful of the compost issues for disposing any commercial garlic - I still had to buy some this year - which could bring along any number of pests or diseases. The alcohol dip for mites is a great idea. (vodka ?)

The good news about garlic viruses, they don't seem to be easily transmitted although the diseased plant material should be burnt not composted. The worst one is called Onion Yellow Dwarf virus - it can be spread by insects that puncture the leaves but doesn't spread by simple contact afaict, and it isn't soil borne, but will overwinter on volunteers or perennial onions. I had a walk around the garden this morning and there's no sign of any symptom on my several patches of leeks, three kinds of green onions, chives, bulbing onions.... thank goodness. So I guess that isn't the problem.

The rounds that seem to be affected are from the same two varieties - Chesnok Red and Leningrad - and some Persian Stars that were grown in the same small tub. So it may have been latent on one or both of these and the spread wasn't too far. Or possibly what I'm seeing is just insect damage and not the same thing - hard to tell on the smaller foliage, which is also drying down really fast. I still need to read more about mosaic virus on garlic, but for now I think I would go ahead and plant these big rounds in a separate place away from the others, and just keep a very close watch on them next season and pull and dispose if there's any sign of virus. Unless there is something more contagious about mosaic than the other.

The worst effect of latent virus seems to be, it can reduce the size of your bulbs. So ultimately the practice of replanting the biggest ones would also help to weed out virus or susceptibility to it or its negative effects. I certainly won't be replanting any of those tiny cloves. The rounds were a good size, so I'm not seeing this concern. I don't understand why growing stock from bulbils restores the vigour of the stock so they say, but maybe it will...
I do think the small size of the Chesnok bulbs can be mostly blamed on the weather and the lateness of these purple stripe varieties - they're just not as well adapted to our short season and cool conditions in the first place. Most of my bulbils last year were from Persian Star, and it's a late one as well... Not a great choice I guess.

So for sure, this time I'm going to focus on planting some bulbils from the healthy Music and Argentina, and try to increase my seed stock of varieties that really do better here.

[henry]

How is your soil drainage? and how wet has your season been. In a cold year garlic needs less water and may be two or more weeks later then normal harvest times. Purple stripe varieties size up at the end of their growing and it is easy to harvest them to soon.

[bower]

The drainage is not bad I think, it's a raised bed mostly organic matter although the subsoil is clay, and for sure it was a very wet year.

I don't think the soil is that great either, it was the best spot I could find that had no alliums the year before. A bit shaded too. Peppers did well there because it's sheltered on the north. I meant to cut some trees that are partly shading that bed but didn't get to it this spring. So it wasn't optimal in several ways.

I didn't know that about the purple stripes sizing up at the end, but I think you're right it was too early to harvest them, their scapes were a good bit later than the Music. So the small size can't really be blamed on a virus. It's my fault for panicking and pulling them all up.

I have a few plants of Persian Star that are in a different bed, and just put up scapes a couple days ago! So late. They look healthy enough, so perhaps they'll have a chance to size up before the season is over.. I read somewhere that garlic should be ready about 20 days after their scapes are cut.... ? Lots of wild guessing here.

[neoguy]

This is something new, never heard that before. I always go by the color of the leaves.

Originally Posted by bower

I read somewhere that garlic should be ready about 20 days after their scapes are cut.... ? Lots of wild guessing here.

[bower]

Originally Posted by neoguy

This is something new, never heard that before. I always go by the color of the leaves.

Yes, they mentioned that too. I found the link, it is what I followed to cure my garlic last year.
http://www.growveg.com/growblogpost.aspx?id=194

[henry]

I always leave some scapes on a few garlic in each bed, when the scapes uncurl and stand tall is when I stop watering and about two weeks later I dig down and check to see if the bulbs are full size and if they are we dig then.

[bower]

Originally Posted by henry

I always leave some scapes on a few garlic in each bed, when the scapes uncurl and stand tall is when I stop watering and about two weeks later I dig down and check to see if the bulbs are full size and if they are we dig then.

Well that's what I'm going to try next year. Thank you, Henry!