RMV :(

This is RMV isn’t it?

  1. Cecile Bruner:

  1. Dr Huey:

  1. Altissimo

Faint, tell-tale oak leaf RMV patterns were obvious in #1 and #3. I would say there is no clear evidence of it in your picture of ‘Dr. Huey’, though; I’d say that discoloration is more likely caused by something else fairly routine like stress during leaf development or insect feeding.

Hmmmm… good news about Dr Huey (best news actually as I want to use it as a rootstock), bad for the other two.

I have read that RMV may be transmitted via soil (I assume through something like a nematode vector etc). Has this been confirmed? My Cecile Brunner is a new plant bought during winter (planted where there has never been roses before) and if I was to buy a replacement would it be a waste of time putting it where this one is, even i I remove and replace as much soil as possible? Can RMV be resident in the soil even if there are no other roses around it? If not, how long can RMV persist in the soil before it is considered clear? I have an old apple orchard on this property. Is this a possible source of infection? Is there any evidence to suggest that insects may be a possible vector? Most of the common sources on the internet state that the virus can’t be spread from one plant to the other and is spread by using infected propagating material. The archives on this website, however, state that it may be transmitted via root contact in crowded situations, pollen, soil, possibly propagating tools. Has pollen been confirmed as a effective source of trasmission? If pollen is a possible source does it infect the developing seed or the fertilised plant or both? My instinct is to bin all the plants that show up with RMV. Is this being too drastic (my rose garden is approaching one acre in size… I would hate to have it spread through everything…)?

I thought the discolouration in Dr Huey was a magnesium deficiency symptom because the potting mix it was in was far too acidic making magnesium unavailable. he new leves coming on, since this issue has been corrected, are not showing any sign of the discolouration. Thought I would ask for a second opinion though…

Simon,

Unless you have a source for virus-indexed (VI) Dr. Huey, I’d suggest you not use it for rootstock.

The surest way to avoid getting RMV in your plants is to use only seedlings, or cuttings from seedlings or plants you know are clean because they’ve never been grafted on and come from someone who follows the same precautions. If you follow this rule, you can be pretty sure of keeping your stock clean.

I recognize that there is a slight chance of getting virus in plants (see the current thread re. other ways of spreading RMV, PNRSV, etc), but it is just that, a slight chance.

Peter

Simon, where are you located? Nematodes are an accepted spreader of rose virus in England; but in the U.S. ???

Part of the confusion is due to the fact that the term “RMV” is a collective name for a group of viruses that infect roses. What viruses are included under this collective name seems to vary with author.

The following is one broad list of viruses that infect roses:

http://www.agdia.com/testing/cropscreens/rose.shtml

The list is not complete as recent research has reported additional viruses in roses.

Link: www.agdia.com/testing/cropscreens/rose.shtml

Simon, the link that you gave on November 26, 2007 in the following thread http://www.rosehybridizers.org/forum/message.php?topid=14084#14149

seems to have been withdrawn.

I used the following link:

http://www.ncbi.nlm.nih.gov/ICTVdb/Aussi/ausidesc.htm

Once I reached that link, I used your my browsers find command with the term rosa to see which viruses have been reported in roses in Australia.

I found:

Apple mosaic ilarvirus

Arabis mosaic nepovirus (VECTORS. Nematodes: Xiphinema diversicaudatum; same as in other parts of the world but occurs only in few places in Australia, it has been found in a rose collection at Burnley, Victoria)

Citrus vein enation - woody gall virus

Potato Y potyvirus

Prunus necrotic ringspot ilarvirus

Strawberry latent ringspot `nepovirus’

So it appears that you may have to be concerned about soil transmission if you have the nematode and Arabis mosaic nepovirus.

Link: www.ncbi.nlm.nih.gov/ICTVdb/Aussi/ausidesc.htm

It doesn’t resemble magnesium deficiency either, but it sounds like it’s not really a problem whatever it was. I’d say that it’s a virtual certainty that your other two roses were already infected with the disease when you bought them.

The following is from New Zealand Journal of Zoology, volumn 24, pages 309-322,(1997):

"Xiphinema diversicaudatum (Micoletzky, 1927)

Thorne, 1939

In the first record of this species for New Zealand,

Dale (1 97 1 ) reported it from Te Puke and Riverhead.

X. diversicaudatum is the virus vector nematode

most frequently recorded in New Zealand (99

records available). The species is widely distributed

in the North Island. In the South Island it is common

in the Nelson and Marlborough area and in Christchurch,

and is present around Wanaka and Alexandra

in the south (Fig. 2B). It occurs almost exclusively

in cultivated soils, where it has been found associated

with roses, carnations, and other flowers, Rubus

ursinus, Thuja and other ornamentals, strawberries,

vegetables and in hop gardens, and in the rhizosphere

of apple, apricot, olive, tamarillo and Citrus trees.

It is also common in turf and Cotula soil from bowling

greens."

If you have this nematode, you may have a very rapid natural spread of rose viruses.

In England 80 % spread (by nematodes) of SLRV and AMV has been documented.

Title: Epidemiology of 3 viruses infecting the rose rosa-spp in the UK.

Author: THOMAS B J

Published in: Annals of Applied Biology. volumn 105, pages 213-222 (1985).

Abstract: “Epidemiology of 3 viruses infecting the rose [Rosa spp.] in the UK. Studies on the epidemiology of arabis mosaic (AMV), prunus necrotic ringspot (PNRSV) and strawberry latent ringspot (SLRV) viruses were made in relation to commercial production of standard and bush roses. AMV or SLRV apparently induced either symptomless infection in rose cultivars and Rosa spp., or leaf symptoms ranging from small chlorotic flecks to severe chlorotic mosaic and, occasionally, plant death. Infection of R. canina ‘inermis’ or R. corymbifera by an isolate of SLRV from R. corymbifera also severely depressed flowering and hip formation. Whereas this isolate could be graft-transmitted to all Rosa spp. tested, isolates from R. rugosa and R. multilfora failed to be graft-transmitted to R. canina ‘inermis’ or R. corymbifera. No difference was detected in graft-transmission tests of Rosa spp., with several isolates of AMV or PNRSV. In plantings of up to 7 yr none of the viruses was transmitted through pollen to healthy roses grown in nematode-free soil, and only SLRV was readily seed-transmitted, particularly in R. rugosa. In soil containing viruliferous nematodes, AMV and/or SLRV were transmitted to .apprx. 80% of healthy plants. AMV and particularly SLRV were each damaging to field-grown maiden rose bushes cv. Fragrant Cloud. SLRV delayed the onset of flowering, and reduced the number and size of blooms. Diseased bushes were less vigorous, and half or none of the AMV- or SLRV-infected bushes, respectively, conformed to the British Standards Institution specifications for maiden bush roses. These results are discussed in relation to the commercial production of field-grown roses in the UK.”

http://cat.inist.fr/?aModele=afficheN&cpsidt=17487462

http://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-3059.1975.tb01869.x

Specifically relating to roses in Australia (I’m in Northern Tasmania):

Info on the Apple Mosaic Virus in Australia:

"Apple mosaic ilarvirus

Probably introduced into Australia; in plant material; during the last two centuries, but exact time unknown, though virus is present in apple trees planted on the Tasman Peninsula about 1835.

PRINCIPAL GEOGRAPHICAL DISTRIBUTION. Known to be present in all parts of the world where apples are cultivated.

VECTORS. Virus spreads but the vector, if there is one, is not known.

DISTRIBUTION IN AUSTRALASIA. Found in New South Wales, in Queensland, in South Australia, in Tasmania, in Victoria, and in Western Australia (Perth, Donnybrook, Manjimup, Albany and Mt. Barker); also found in New Zealand.

INCIDENCE AND DISTRIBUTION. Less than before because virus- tested stocks are now used i.e. budwood and rootstocks.

REPORTED AUSTRALIAN HOSTS. Known Australian host plants

Aesculus hippocastanum,

Corylus sp.,

Humulus lupulus,

Malus domestica N.S.W., Tas, Vic,

Malus sylvestris Qld,

Prunus cerasus,

Prunus domestica,

Rosa sp. N.S.W., S.A., Tas, Vic.

AGRONOMIC FACTORS. Varieties known to be susceptible are Golden Delicious and Jonathan. Granny Smith display considerable tolerance of mosaic when grown on Sturmer Pippin seedlings or Malling-Merton 104 rootstocks. Yield of crops in apples is moderately affected, or is severely affected in Red Jonathan, in which infection is not latent. Measures to minimize losses: use virus-tested stone, pome and rose stocks.

REFERENCES.

Basit, A.A. and Francki, R.I.B. (1970). Aust. J. biol.

Sci. 23: 1197.

Basit, A.A., Francki, R.I.B. and Kerr, A. (1970).

Aust. J. biol. Sci. 23: 713.

Garrett, R.G., Cooper, J.A. and Smith. P.R. (1985).

“Virus Epidemiology and Control”. In: The Plant

Viruses, p. 269. Ed. R.I.B. Francki, Plenum Press,

New York.

Harvey, H.L. (1957). J. Agric. West. Aust. 6: 427.

Johnstone, G.R. (1969). Phytopath. Z. 65: 155.

Johnstone, G.R. and Boucher, W.D. (1973). J. hort.

Sci. 48: 175.

Sampson, P.J. and Johnstone, G.R. (1974). J. hort.

Sci. 49: 183.

Wood, G.A. (1979). “Virus and virus-like diseases of

pome fruit and stone fruit in New Zealand” New

Zealand D.S.I.R. Bull. No 226, p. 21. Mosaic

symptoms in roses in Australia are most likely due

to prunus necrotic ringspot and not to apple mosaic

virus infection.

Data collated by J.A. Cooper, 1986; R. Ikin, 1987; G.R. Johnstone, 1987; G.D. McLean, 1985."

So seeing this assumption on the cause of mosaic virus-like infections in roses in Australia:

"Prunus necrotic ringspot ilarvirus

Probably introduced into Australia; in plant material; during the last two centuries, but exact time unknown.

PRINCIPAL GEOGRAPHICAL DISTRIBUTION. Found worldwide in temperate regions where Prunus spp. and roses are cultivated.

VECTORS. Virus spreads without the help of a vector and spreads through pollen carried by honey bees.

DISTRIBUTION IN AUSTRALASIA. Found in Melbourne, Kyneton, Irymple and Tatura in Victoria, in New South Wales, in Queensland, in South Australia, and in Western Australia in Pickering Brook, near Perth, Manjimup and Donnybrook; also found in New Zealand.

INCIDENCE AND DISTRIBUTION. Since the rosette and decline' was recorded. A dual infection of prunus necrotic ringspot and prune dwarf viruses increasing gradually in Victoria in an orchard of the variety Golden Queen’ from 0.9% to 91.5% over 11 years and in `Pullars Cling’ orchard from 1.5% to 29.6% over 5 years (Smith et al., 1977).

REPORTED AUSTRALIAN HOSTS. Known Australian host plants

Humulus lupulus Tas,

Prunus armeniaca Qld,

Prunus avium N.S.W., Qld, S.A., Tas, W.A.,

Prunus cerasus Qld, Vic,

Prunus domestica Qld,

Prunus persica N.S.W., Qld, Tas, Vic,

Prunus sp. N.S.W., Tas,

Rosa sp. Qld, Tas, Vic.

AGRONOMIC FACTORS. Varieties known to be susceptible are the peach cultivar Golden Queen that is very sensitive to combined infection with prune dwarf and prunus necrotic ringspot virus. F12/1 cherry rootstock and some sweet cherry varieties show `tatter-leaf’ symptoms, when infected with prunus necrotic ringspot virus. Yield of crops is moderately affected . The effect on fruit yield is most obvious when a combined infection of prune dwarf and prunus necrotic ringspot virus occurs, which can result in a 66% yield reduction in Golden Queen. Measures to minimize losses: use virus-tested budwood and rootstock. Plant healthy trees some distance from older infected trees, to reduce the likelihood of virus infection via pollen.

REFERENCES.

Basit, A.A. and Francki, R.I.B. (1970). Aust. J. biol.

Sci. 23: 1197.

Bjarnason, E.N., Hanger, B.C., Moran, J.R. and Cooper,

J.A. (1985). N.Z. Jl agric. Res. 28: 151.

Munro, D. (1983). Proc. 4th int. Congress Plant Path.,

Abst. No 479.

Munro, D. (1987). Aust. J. agric. Res. 38: 83.

Smith, P.R. and Challen, D.I. (1972). Aust. J. agric.

Res. 23: 1027.

Smith, P.R. and Challen, D.I. (1977). Aust. J. exp.

Agric. anim. Husb. 17: 174.

Smith, P.R. and Neales, T.F. (1977). Aust. J. agric.

Res. 28: 441.

Smith, P.R. and Stubbs, L.L. (1976). Aust. J. agric.

Res. 27: 839.

Smith, P.R., Stubbs, L.L. and Challen, D.I. (1977).

Aust. J. agric. Res. 28: 103.

Stubbs, L.L. and Smith, P.R. (1971). Aust. J. agric.

Res. 22: 771.

Wood, G.A. (1979). "Virus and Virus-like diseases of

pome fruit and stone fruit in New Zealand", New

Zealand D.S.I.R. Bull. No 226, p. 39.

Data collated by J.A. Cooper, 1986; R.A.C. Jones, 1987; G.D. McLean, 1985."

So it is commonly transmitted by infected pollen.m My rose gardens are located next to my apple/nectarine/plum/pear orchard… I live in a highly agricuoltural part of Tasmania where the crops grown in adjacent farms are onions, opium poppies, pyrethrum, potatos, carrots, and peas. Immediately next to me potatoes, onion and poppies are being grown on several hundred acres and the farmer uses nematicides to reduce the incidence of parasitic nematodes in his crops (which, unless he rotates his chemcials effectively might mean there are resistant populations).

I am beginning to wonder whether I will be beaten before I start on hybridising my own roses here :frowning: none of mine are showing signs of virus now but if my pollen/seed stock becomes infected it won’t matter how good the new seedlings are they can never be released :frowning:

Source:

Link: www.ncbi.nlm.nih.gov/ICTVdb/Aussi/ausidesc.htm

I wouldn’t be worried about it too much. If these viruses indeed infect your roses effectively, it means that roses in nurseries will be infected even more effectively, since the concentration of hosts is much greater than in your garden and surrounding area. So that means that roses you buy from nurseries there will be infected no matter what and then it doesn’t really matter that your seedlings are infected also.

On the other hand, if roses you buy in your area show no signs of infection, then the effectiveness of infection by harmful viruses is probably low. This means that your seedlings will probably not be infected very effectively also and probably stay clean (if you follow normal hygienic and precautionary measures).

In both cases my reasoning is that your roses can be released, because other’s roses are released also (assuming you take the same measures others take, e.g. grafting only on virus-indexed rootstock)

Rob

The infected ‘Cecile Brunner’ is newly planted and hasn’t yet flowered eliminating pollen as the likely mode of transmission. Whether it was due to grafting onto virused understock or it contracted the disease after it was planted via another mode/vector I cannot say.

The infected Altissimo has been here for many years and again I can’t say when or how it was first infected.