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Instant FMV?

Here are about 50 seedlings saved this year. Most have about 6-10 leaves on them at this point and are 6-18" tall and maybe 5 months old at most. The interesting thing is that they all are showing signs of FMV already. That means that either the seeds were infected, or the transmission of FMV is very simple, easy and quick.







Interesting Jon, i read in past they do not come from seeds themselves.
Don't believe what you hear and only half of what you see i suppose as the ole saying goes.
Thanks for posting that Jon.

Did the seedlings come from the same fig, or are they from various figs?

Suzi

It's interesting because I took cuttings off one of my heavily infected FMV trees in So Ca and have grown them in Phoenix. Absolutely no sign of FMV there. Of course they are carrying the virus still, but no signs or symptoms of it.

I wonder how much is known about FMV.

If they are all from the same mother tree then I think the virus came through the seed. LMV (lettuce mosaic virus) can be transmitted that way. Otherwise mite populations could be very high because of weather.

Long story, but the seeds all came from the same tree, but not the same fruit.

I assume that the seeds do not transmit the infection, so the point is how easy and how quickly the new seedling have become infected. It would be interesting to repeat this in a location where there are no fig trees and no source of infection and see if indeed it was in the seeds, or not.

As reported by Flock and Wallace in 1957, eriophyid mites can transfer mosaic disease in less than 10 days.

http://californiaagriculture.ucanr.org/landingpage.cfm?articleid=ca.v011n01p12

Mites are impossible to see, for me anyway, without magnification. So, they are easy to miss. It is entirely possible that you have fig mites in your growing area and the mosaic disease was transferred from one or more of your infected plants. If you want seedlings to stay mottling disease free, they need to be grown in a restricted area or clean greenhouse environment from what I read in the scientific literature.

Because FMV is an RNA virus and RNA viruses normally have error-prone polymerases, there are lots of minor variants of FMV. There is not much published on the degree of variation as yet or how the variants might impact mottling disease. Just to make things yet more complex, at least 8 additional fig viruses that cause mottling have been identified in the past few years causing the disease to be referred to by the scientists as fig mosaic (or mottling) disease, FMD for short. They are:

Fig Leaf Mottle-Associated Virsus 1 & 2  (FLMaV 1 & 2)

Fig Mild Mottle-Associated Virus  (FMMaV)

Fig Latent Virus 1  (FLV-1)

Arkansas Fig Closterovirus 1 & 2  (AFCV 1 & 2)

Fig Badnavirus-1  (FBaV 1)

Fig Cryptic Virus  (FCV)

Several of the above viruses are also RNA viruses with meaningful variation between different isolates just to make the puzzle more annoying.

The Falk lab at UC Davis and the Martelli lab in Italy were the 2 groups to isolate and get the genetic sequence of FMV.

http://apsjournals.apsnet.org/doi/pdf/10.1094/PDIS-93-1-0004

http://vir.sgmjournals.org/content/90/5/1281.full.pdf+html

It appears that FMV is not transmitted in seedlings. However, FLV-1 is reported to be transmitted in seedlings. I do not know about the other viruses.

http://sipav.org/main/jpp/index.php/jpp/article/view/563

 

Reports are starting to appear of efforts to screen trees across broad areas for FMV and other viruses. The ones that I have seen find FMV broadly distributed. They are using PCR based methods to detect. My guess is they are getting some false negatives even when >90% rates of infection are found. I hope this is useful.

Good luck with your trees!!

Quote:
Originally Posted by pitangadiego
Long story, but the seeds all came from the same tree, but not the same fruit.

I assume that the seeds do not transmit the infection, so the point is how easy and how quickly the new seedling have become infected. It would be interesting to repeat this in a location where there are no fig trees and no source of infection and see if indeed it was in the seeds, or not.


Jon perhaps try starting another by seed indoors and sterilize the soil yourself via high heat to help not get any knats cause those are a real pain in the house.
Then see what happens.

if i'm not mistaken, the seed can carry virus. if the virus is in the reproductive cell, and when cell splits, one or both side can carry them.

My thinking is, Why woundn't the seed carry FMV? It is all part of the tree. Any and all parts of tree would be infected. Yes? No?

luke

It seem we should not worry about FMV if plant is a strong grower,because it must be a mild virus,that the plant can cope with.

Quote:

http://en.wikipedia.org/wiki/Plant_virus#Seed_and_pollen_borne_viruses

Plant virus transmission from generation to generation occurs in about 20% of plant viruses. When viruses are transmitted by seeds, the seed is infected in the generative cells and the virus is maintained in the germ cells and sometimes, but less often, in the seed coat.
...
Little is known about the mechanisms involved in the transmission of plant viruses via seeds, although it is known that it is environmentally influenced and that seed transmission occurs because of a direct invasion of the embryo via the ovule or by an indirect route with an attack on the embryo mediated by infected gametes.
...
Many plants species can be infected through seeds including but not limited to the families Leguminosae, Solanaceae, Compositae, Rosaceae, Curcurbitaceae, Gramineae. [5] Bean common mosaic virus is transmitted through seeds.

Quote:
Originally Posted by Herman2
It seem we should not worry about FMV if plant is a strong grower,because it must be a mild virus,that the plant can cope with.



Herman hope you are right. One of the plants I just bought is showing signs of FMV - not the ones I bought from you  . I have it separate from my others and am hoping that it will not go to the others. I'm still not quite clear on this virus as to whether it is harmful or not to trees in the long term and in young trees.
The tree that is exhibiting all the mottled yellow signs - is there anything anyone does to lesson the degree as this is a very young tree?

Patty:If you read The
,DWD2 post ,it is clear that not all Fig mosaic viruses  are the same,and affect the plant just as bad.
I have seen plants that grow very well,with Fig mosaic virus and other ,they just do not want to grow.
The plants that do not want to grow clearly must be the ones having the bad virus,and that is the plants we should avoid growing.
Not because it will spread to other plants,because I am sure it does not spread without the agent,(aceria Fici),but because it is just too hard to  have a good production from  such a plant.
One cultivar I could not get anything out of it ,despite best care was Calvert.
It just do not want to grow period,but lately I resolved the problem,because I found out after a lot of Observations,on plants that JH Adriatic is the same cultivar minus Fig mosaic virus.

Thanks Herman for that clarification  :-)



Quote:
Originally Posted by Herman2
Patty:If you read The
,DWD2 post ,it is clear that not all Fig mosaic viruses  are the same,and affect the plant just as bad.
I have seen plants that grow very well,with Fig mosaic virus and other ,they just do not want to grow.
The plants that do not want to grow clearly must be the ones having the bad virus,and that is the plants we should avoid growing.
Not because it will spread to other plants,because I am sure it does not spread without the agent,(aceria Fici),but because it is just too hard to  have a good production from  such a plant.

Luke,

Virus can be in the tissue without being inside the cell.

You can have bacteria and virus in your bloodstream, but that doesn't mean that it has entered your cells, and more specifically you reproductive cells.

Jon, That is very interesting to hear. It is always good to learn more, and one of the best ways are to experiment. Being fairly new to figs, I'm still trying to rap my hands around this FMV thing. Because I live in the Northeast, it affects me more then others in a warmer climate. Since I have the space to grow, I'll experiment with many figs even if others have tried. One of my experiments this year was to plant a Scotts Black in the ground and grow one in the pot. Both being the same age and size. The one in the ground I didn't do anything with, just planted and forgot it. Well I did pinch it. The one in the pot got everything. Compost, fertilizer and lime. Watered properly and also pinched. The one in the ground is twice as big and shows no sign of fmv, while the one in the pot is showing signs of fmv. My final results will have to wait till spring to see how well this holds up. it will be protected.

luke

Some viruses can survive in the embyro of the seed as well not just the seed coat.

I hope I can clarify a couple of points here. As I mentioned above, according to the literature labs grow seedlings in glasshouses (the term used for greenhouse) or pots under a screen system to get FMV free trees. There are many scientific papers starting with one published with Condit in 1933 demonstrating that FMD/FMV is NOT seed transmissible. Any of you interested in learning more about seed transmission of plant viruses may find this review helpful.

 

http://www.dias.kvl.dk/EJCVetc/Johansenetal1994.pdf

 

Gina, thank you for the Wikipedia link! I read a recent paper that I neglected to grab as a pdf and now can not find saying current thinking is ~30% of plant viruses can be seed transmitted. The upward revision comes with the finding that some viruses seed transmit inefficiently causing some to be missed initially. In the case of fig viruses, FLV-1 is the only one to date demonstrated to be seed transmitted. FLV-1 is reported to cause a mild mottling condition at worst and is apparently not the cause of significant FMD by itself. Many trees are infected by multiple viruses. The degree to which FLV-1 might interact with other viruses and cause significant FMD is unknown.

 

http://www.sipav.org/main/jpp/index.php/jpp/article/viewFile/546/334

 

Herman, as usual, I think cuts right to the core of the problem and supplies us a big dose of common sense. It seems to me he has constructed a pretty effective solution for himself by vigorously working to only retain the healthiest trees in his collection. Although, I have a fair bit of experience with citrus, apricots & plums, I have only been playing with figs for 18 months. So, I pay close attention to Herman's experience(s) as he posts. My reading of the literature is that the scientists actively studying FMD believe that FMV is the usual cause of significant FMD as opposed to mild mottling. The degree to which the different variants of FMV cause greater or lessor disease is unknown. The degree to which the other fig mottling viruses I list in my post above cause significant FMD alone or in conjunction with any of the other viruses is unknown. The degree to which HOW you grow your fig trees might affect whether they show FMD is unknown although anecdotes like luke's above surely suggest there is something there. I think it is clear that it is a complex problem & there is a lot yet to be discovered. So, there is a lot to be said for Herman's common sense, practical approach.

 

Relative to whether these fig viruses are intracellular (inside the cell)  or intercellular (outside the cell), the statement that bacteria and viruses need not be intracellular is correct. However, for a virus to replicate and cause pathology, it must be intracellular. Bacteria and fungi do not normally need host cell machinery to reproduce and can exist either intracellularly or intercellularly and cause disease either way depending on the particular microorganism.

 

There is one intriguing possibility that might supply a possible treatment for FMD. Aspirin. Salicylic acid (aspirin) is produced by plants in response to infection by pathogens and activates the plant's innate immune system. It has been demonstrated that treatment with salicylic acid can prevent or limit several plant infectious diseases.

 

http://segenetica.es/cng2/cng2008/biblio/Ref-Marc-Valls---Jones-and-Dangl-Nat06.pdf

 

http://igitur-archive.library.uu.nl/bio/2009-0512-200821/NatChemBiol-Pieterse-2009.pdf

 

This is my first year propagating from cuttings. All but one of my cuttings are from Encanto (thanks Jon!!!). Two of my 3 Sicilian Black Italian cuttings are doing well and showing little, if any, sign of FMD. However, one started showing significant FMD several weeks ago. It had been doing well but slowed up as the FMD appeared. I do a foliar spray of worm casting tea that contains salicylic acid on my tomatoes roughly every week. So, I decided to spray the fig too. After 2 sprayings, the leaves have greened considerably and the mottling is clearly decreased. How much of that is due to the aspirin or nutrition from the worm casting tea or both I can not say. My plan is to try to test for any aspirin effect more carefully next year on what I think many (most?) would agree is a true FMD challenge: cuttings from UC Davis. I will propagate some with and some without routine salicylic acid treatment and see if there is an impact on FMD appearance. I am assuming that they provide several cuttings of each cultivar as Jon did. If not, I'll have to try something else.

 

Good luck with your trees!

DWD2. Not sure where you came from or where you have been all my life but I very much appreciate your weighing in on this. I am definitely learning. And someone is doing the heavy lifting in this case, which is a definite plus. I only wish I had time to digest all the literature that is out there.

DWD2, thanks for all the references and what concentration of acetylsalicylic acid do you use?

Jon, thank you for your kind words! And THANK YOU for this site! If you have technical questions, I am happy to help. After 30 years in science, tracking down references and separating useful information from the useless is reflex.

Bob, I use 1 tablet (325mg) per gallon. That is probably a little excess, but I am too lazy to be splitting aspirin tablets. My best guess is that I would hesitate going higher than that amount. This is a pretty active area of research. Based on what I have seen to date in a number of papers, most groups are trying 225mg to 250mg per gallon (when you convert from liters), which is typically derived from receptor saturation per leaf area, a very reasonable approximation to my mind. Receptor saturation probably varies from plant to plant somewhat, but probably not dramatically. In the case of my fig, the initial response appears to be positive. I will try to remember to update in 4 to 6 weeks or you should feel free to send me a PM.

Good luck with your trees!

Ha Asprin ...interesting .Any one else try this ?

  • jtp

Makes sense. FMV can be a headache. :)

So, to make it simple, what is the best treatment for young plants with FMV?

I have two newly purchased plants exhibiting FMV, what should i combine and spray?

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