I dug up eight small rooted layers/suckers around a fig tree this spring that the owner described as a yellow/white good for fresh eating.  They are in pots and rank in size from 6" to 2'. 

I have had no luck in grafting it to my frankenfig, and today I got a wild hair and thought I'd try again using a whole plant, one of the little ones, and incorporate some roots along the far end of a bark graft. 

Up on desoiling the plant, I think I saw why the parent tree had looked so forlorn, RKN







Is it RKN?

The plants were collected bare root, and are confined to pots, originally with uncontaminated soil, but surely runoff has contaminated the surrounding soil by now. Agree?  Is there anything I can do in any case now to prevent the whole yard from eventual contamination?

Can I take cuttings of the above-ground portions of these plants, dispose of the soil, and root/graft RKN-free trees?  ie, is the above ground portion of the trees uncontaminated?

thanks!

Take cutting and re-root and destroy the soil in the pots. You can throw it away or if you want to reuse it nuke it. 

I would plant it in a pot, then do an air layer. Once the air layer is growing good remove it from the parent tree then destroy the infected tree, soil and all. If you are going to reuse the pots I would wash them out with hot water and let them dry a few days or better yet put them aside and use them next year to be safe.

Were I to go through with my plan to graft the pictured plant into my big tree, roots and all, would the big tree be contaminated, or is RKN strictly a soil-borne, root-harbored disease?  This is theorectical, as I likely wouldn't take the chance anyway.  Just curious.

RKN are worms that live in the roots. If you cut open one of the root knots you should see tiny tiny worms come out. They live in the roots. Taking a cutting or air-layering won't transfer them to the new tree. 

Right, but If I were to graft the pictured specimen into a large host tree, incorporating the root into the graft, would the nematodes survive and spread within the tree?  Just a question about the nature of the nematodes themselves. 

A very different question is whether use of the root increases/decreases/indifferent in determining the likely success a graft, which is what I set out to find out in the first place before the RKN discovery.

I will be air layering the two trees large enough to do so, and try rooting cuttings and grafting the rest.

Thanks

They could maybe spread within the tree's water vascular tunnels. They will most likely end up back in the roots. I think the actaully nematode is too big, but the eggs might make it. I wouldn't try it at all. 
Would you take a diseased organ for a organ transplant?

Hopefully someone who is an expert on grafting will comment. 

Done and done with the air layering




I one-cut girdled (did not remove bark) and scuffed up this one



 

The cut pot allowed me to sneak the whole plant in without removing any leaves.





You can see one of the scrapes at the to of the leaf litter added to the botoom to prevent over drainage, then filled with old compost.





trimmed the leaves off all three branches of the other one

I have seen trees that have lumpy bumpy bark above the soil line that were infected with RKN. I would inspect the airlayers root system a bit down the road when you up-pot them just to be safe.

brackishfigger,
Nice air layer technique.
Here's a Website with lots of info on Root Knot Nematodes. And their graphic of the Nematode Life cycle..
Good Luck.

If your galls were on the extremeties could you remove those roots, sanitize the rest and replant in clean medium? Unless there were J2's present you might could save a small plant that might be two small for air layering or would it be better to let it grow out hoping to get it large enough to air layer?

When I did this operation I cleaned the area pretty good and covered the infested soil with turface and some plastic wrap. You have to be careful that the infected soil doesn't splash into the new soil when watering or raining.

I have moved the affected plants/pots to the far end of the drainage of my property, and placed them on pavement.  I have ordered the most nematode-toxic marigolds  offered at Lee "guardian" to plant around the area the pots had been sitting.

I do wonder if a potted plant can be salvaged with fumigants:  place a dry cleaning bag around the pot and have at it.  Any suggestions on the appropriate toxin?

i think RKN is the only thing i'm really worried about when it comes to figs.

Yeah, once an in-ground is infected, the soil is contaminated, I think your done for. . .

Just an update on those air layers.  All died, getting the bark eaten away by something claiming many of my cuttings, too.  All future pots/soil get microwaved prior to use with cuttings!!

THe pic show what the dying air layer looks like before it perishes, and the debarked branchs of the other two air layers are coming out to the left of the little pot.

 

Any thoughts on the likely culprit?

http://forums.gardenweb.com/forums/load/pests/msg1222134928674.html  this is from another garden site, but on point.

That's what all cuttings look like when they die.  What I mean to say is, I don't think it's a critter that munches the bark, which then kills the cutting.  The cutting dies, for some reason.  Usually some form of rot starts to affect the part in the soil.  Many roots may die, bark will soften and decay.  Once enough roots die, or the bark decays enough, the cutting can no longer support the water needs of the leaf.  So the leaf droops and falls off.  By this time the damage is irreversible.  If I had to guess a culprit, I'd say too much moisture in the soil.  But even in good conditions some cuttings/airlayers will die. 

I've been reading up on soil bacteria and fungus and there are types that go after those nematodes, it will look it up again and get back to you...

Are the nematodes on grape roots the same nematodes?

There are a BUNCH of different kinds of root nematodes.  Even on fruit trees if you get a nematode resistant root stock that root will not be resistant to all the RKN just the more common ones.  If you happen to live in an area with the more aggressive RKN types......well you have my sympathies.  

Thanks Wills. 

So can nematodes from grapes spread to the figs or vica versa? 

RKN can infect many plants; vegetables, fruits, and more.

Hello everyone, I have experimented with RKN, and with the help of the good doctor from this forum,
I have applied peroxide 2 % to the pots and inground and the results have been super.
I have not killed any fig plants only a strawberry plant. No measuring, just go with the feel.
Mulch, Mulch, Mulch like the expert says with the inground plants, and you will be fine.
Enjoying figs in Cape May Court House NJ.