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rrd

16 years ago

going through old threads, this horrible, horrible disease has mortified me. I have never heard of it, much less seen it before. It seems to be in the nature of these things that global infections are rife. We are still reeling from Dutch Elm, sudden oak deaths, chestnut leaf miner and other horrid pests and diseases. What are the chances of RRD arriving in the UK?

Comments (7)

  • 16 years ago

    found a long article by Ann Peck - very helpful but totally horrifying. My great sympathies to anyone trying to deal with this menace.

  • 16 years ago

    I've been watching to see if you get any responses. Ann Peck knows as much about it as anyone you could find, so you have gone to the source.

    I'm interested, but don't know the answer. I sincerely hope it does not. Since RRD is spread by a wind-borne mite, I don't think it would cross the ocean without human assistance. Still, there are always people who flout import quarantines, so I suppose it could happen.

    I for one do hope that this disease does not spread past its present range, and that we manage to control it even there. I suppose it is too late to hope that we eliminate it altogether, which would be the best outcome.

    Rosefolly

  • 16 years ago

    I've been thinking about this question, and at first I thought surely the mite would not be able to cross the ocean, BUT - I bet it does get to you eventually.

    Human assistance - Rosefolly said it right there - if vendors get roses from the US, there are bound to be some roses that are affected without showing it immediately.

    Case in point: I bought a rose from a local nursery that they had purchased from another vendor. It looked great - until later that summer when it showed signs of RRD. There were a couple more roses that I watched carefully, but nothing ever came of them.

    Now, it may be 10 years or more (or less), because not all of the US is affected just yet. But with vendors selling to the nurseries, people purchasing from mail order companies, and some of those companies reliable and others not, most of us are bound to run across it at some time, whether it is introduced from us or from a neighbor down the way that bought an affected plant and didn't know it. And it would be my guess that it will cross the ocean in a mail order at some point in the future.

    Just my guess.

  • 16 years ago

    It may take a heroic effort to keep it out of the UK, but there is hope.
    It seems I read somewhere that the UK has eradicated rabies and has successfully kept it out of the country?
    If that is true, perhaps something like RRD can also be kept out? I realize those are very different issues, but it's just something to think about.

    We'll keep your fingers crossed for you. By the way, there are large portions of the US where RRD has not been an issue ... yet.

    Randy

  • 16 years ago

    Hi, Campanula,
    So far, the RRD isn't anywhere but North America.
    Some similar symptoms have been found in glasshouse rose culture in Poland, but they have been tied to a phytoplasma and are thought to be leafhopper transmitted. Papers by Kaminska et al. are the main source of that information.
    In North America, several groups of scientists have so far found NO evidence that RRD is phytoplasma caused and there is a virus-like disease that may prove to be the cause. The only known vector so far is an eriophyid mite. Absent the mite, there is no spread.

    In Great Britain, there has been a Black Current disease known for over a century. Only with molecular studies in teh last decade have the scientists found that it is a combination of diseases and they have described the virus that is Black Current Associated Virus. It is vectored by a eriophyid mite, but a different mite that the RRD mite.
    People continue to grow Black Currents, but it's not as easy as it once was.
    Other similar diseases inclue PigeonPea Sterility, Plum Pox, Peach something or other, a date palm disease, and on and on.

    To my mind, people who love plants can't stand by and let ignorance take over. Ignorance says that there are solutions for everything; we just have to wait for nature to find them. With diseases, we need to be aware that things are going wrong by knowing what is right and what isn't .

    The first time I saw RRD, I was having a potluck dinner for my local rose society. Someone brought six canes of Double Delight into my garden and was waving them around and she wanted to know why her Double Delight had stopped blooming. She had bent the canes into rounds with a 12 inch diameter and they didn't snap; they were hyperthorny; the leaves were deformed and spaced every inch on the canes and all she noticed were that the canes didn't have blooms.

    There are no easy answers. One of my brothers in law earned his PhD in Molecular Biology; his answer: find a rose with resistance and splice those genes in.
    Except I had a short list of roses that I thought might have resistance and all have come down with RRD.

    There are no easy answers.

    But you can't know how important to the collection of data GardenWeb Rose Forums were. This community came together and shared information effectively. This has been important in understanding the spread of the disease. I know the 'where' is always several years behind the actual spread, but at least we keep trying.

    Ann

  • 16 years ago

    yes Ann, you are absolutely right on so many things. Ignorance is the worst pest of all. On my allotment, Big Bud mite is rife in blackcurrants - a tour around showed every plot has it. We grubbed ours up and burnt them and warned every other plot holder but so far, not one has been removed - because the plants don't actually die - they get reversion disease, smaller distorted leaves and a much reduced crop but still go on....and so the problem continues. We resort to using horticultural fleece for loads of things - out plot looks really weird covered in white material but we can keep the many pests, from flea beetles to foxes off our crops.
    We are a bit complacent in the UK sometimes, the island mentality and all, but we do have a global economy with massive human movement around the globe - we've just recently got the harlequin ladybird from mainland Europe now. Worse, we cannot trust our leaders who all have their own agenda, usually venal self-interest and profit. Thankfully, we do have forums like this where we can work together and benefit from some serious expertise and where the only agenda is to maintain healthy, vigorous and diverse plants.

  • 16 years ago

    So far, the RRD isn't anywhere but North America.

    Interesting.

    That would seem to suggest it's truly a new rose disease - although on the other hand the strain of Phytophthora ramorum that causes sudden oak death on the West Coast (it infects a huge number of other plants besides oaks, doing varying degrees of damage to them) hasn't ever been found anywhere except the US West Coast, and yet was identified as a sister strain of the same species that had just the year prior been identified as a new rhododendron disease in Europe.

    It's odd how sometimes diseases seemingly arise out of nowhere.