Dear Dave: Thanks, I wonder why certain genera are hard to propagate by meristem culture, I hope it is simply 'hard' and not impossible. Lot of talk regarding virus, apparently some think all variegation in plants is caused by virus, many Camellias have a non lethal virus which causes pleasing variation in the foliage. I have one such plant growing in close proximity to other Camellias for at least 25 years, no transfer of this non lethal virus has taken place. I am wondering if, as is the case with ourselves, virus is present but remains inactive until it comes in contact with a 'trigger' virus, for want of a better name. I often wonder if such a 'dormant' virus, plays a part in other aspects of growth but not, to date, understood. I feel but not yet convinced that such symbiotic relationships with virus and the plant play part in growth we do not understand. Because a plant does not show it has virus when tested, does not mean, in my mind that NO virus exists in the plant. Rather I think it (a virus) has not encountered the trigger to allow it to assume its destructive work. This could also be considered perhaps as providing an immunity to problems. The virus free Enchantment we obtained, came down with other problems, faster clonal breakdown, as an example, which makes me think virus can help, in some way in perhaps a juvenile ( i.e. not able to be detected by present methods) form but is part of all plants just as certain diseases are in us all the time but not apparent until 'triggered' Just the musings of an old Plymouthian!! Spent too long on the Hoe! Cheers, John E. Bryan David Fenwick wrote: > > Hi John, > > >>>>>I read with interest your omments regarding virus. It seems to me that, > if there is a rare species or historically important cultivar with > virus, propagation by meristem culture might result in the production of > a virus free plant. Not all plants are able to be propagated by such > means, but an effort should be made to preserve such important plants in > this way. > > I fully agree, sadly Crocosmia do not microprop so well, this is why I said > that 'post micropropagation trial' may be neccessary, to select the closest > clone to the original plant. Basically Crocosmia are genetically unstable > when micropropagated, one grower I know got three distinct hybrids when he > tried to microprop one of his new hybrid, he gave up in the end. > > >>>>It might not be possible to get an establishment to undertake such work, > but if of such importance an effort should be made. Are there such > establishments which could undertake such work? > > Yes there are establishments that could do it, either universities or > commercial facilities, I think my role though is basically to promote the > need for this to be done. I'll let you know if it's ever offered. > > >>>> it seems to me every effort should be made in this regard rather than > destroy important collections. > > What we have to look at is the number of hybrids that have been developed in > the past by our forefathers, sometimes these are referred to as heirlooms in > the US. In the UK there were many fantastic advances in the production of > garden worthy hybrids from the Victorian era until the outbreak of war in > 1939. This makes it historically important to conserve, and for the sake of > the 'gene pool', for it could be used now to make further advances in > hybridisation. > > This 'gene pool' may also be medicinally important. One example of this is > in the case of Germany. As Germany could not get good supplies of medicinal > herbs in the early 20th century, and they embarked on a breeding program to > develop their own, one genus developed in particular was Aconitum. The > plants that were produced contained highly increased levels of 'active > ingredient' than any other hybrids produced at that time. Hence on finding > and conserving these plants we may now find plants that could be cost > effectively used at the moment, either by large companies, or third world > countries. > > If found these latter plants would be the first to have their viruses > eradicated through micropropagation, it's all down to economics at the end > of the day.. > > Best Wishes, > Dave > > Websites: > http://www.theafricangarden.com/ > http://www.crocosmiaheritage.com/ > > Address: > David Fenwick > NCCPG National Collection of Crocosmia with Chasmanthe and Tulbaghia > The African Garden > 96 Wasdale Gardens > Estover > Plymouth > Devon > England > PL6 8TW > > ----- Original Message ----- > From: "John Bryan" <johnbryan@worldnet.att.net> > To: "Pacific Bulb Society" <pbs@lists.ibiblio.org> > Sent: Monday, March 03, 2003 6:14 PM > Subject: Re: [pbs] Virus in bulbs > > > Dear Dave: > > I read with interest your omments regarding virus. It seems to me that, > > if there is a rare species or historically important cultivar with > > virus, propagation by meristem culture might result in the production of > > a virus free plant. Not all plants are able to be propagated by such > > means, but an effort should be made to preserve such important plants in > > this way. I remember we propagated the Lilium 'Enchantment' by this > > means and raised good quantities of this virus free plant. > > It might not be possible to get an establishment to undertake such work, > > but if of such importance an effort should be made. Are there such > > establishments which could undertake such work? it seems to me every > > effort should be made in this regard rather than destroy important > > collections. Cheers, John E. Bryan > > David Fenwick wrote: > > > > > > >>>>>There is a lot of virused material in the trade and > > > several nurseries have a few cultivars of Crocosmia that are terribly > > > virused. Any comments Dave? In my opinion it was viruses who wiped out > all > > > those fabulous Crocosmias you mentioned of late. > > > > > > Dave here, > > > Yes, Alberto I'd like to raise a few points. > > > > > > I hate to contradict you but I sincerely doubt viruses were responsible > for > > > wiping out many of the old Crocosmias, bad winters and Adolf Hitler were > > > primarily the two main causes; but I am considering 'disease' also and > for > > > reasons I will discuss. > > > > > > It my opinion that the commercial popularity of a genus, any genus, and > its > > > sale, has a direct relationship between the spread and increase of pest > > > populations and disease. Hence the more people that grow Crocosmia, the > > > higher the level of disease and increase in pests, many of which will be > > > virus vectors. Given that when plants are propagated, pests can be too, > and > > > transfered as unseen eggs, instars or larvae, and fungi, bacteria and > > > viruses transmitted unseen systemically. > > > > > > In my case, as a national collection holder it is very important for me > to > > > continually seek healthy stock, or know where I can get it from, and > mainly > > > because any collection of this size and of same genus can be considered > a > > > monocrop. In some respects monocrops are much easier to look after and > > > manage, however, pests which translocate viruses have a devastating > > > potential, and thus the correct proceedures need to be taken regarding > pest > > > and disease management, and crops need to be continuously supervised. > > > > > > Having followed Crocosmia hybrid development very closely from the > breeding > > > of Crocosmia x crocosmiiflora in 1879 it is possible to see a pattern > emerge > > > in the development of hybrids, their fashion trends and decline. However > > > this pattern is greatly masked by both the first and second world wars, > but > > > I am certainly looking into the fact that the higher the sale and > fashion, > > > the quicker the decline and probable extinction, but this is difficult > when > > > you have to consider two world wars. It is more probable though that > plants > > > have suffered because of changes in the economy, garden ownership, harsh > > > winters, and lack of time before and between wars to release these > hybrids > > > commercially. > > > > > > This commercial frequency, the dates plants were sold, from specific > > > nurseries, eg. such as with Lemoine, France, can be recorded in his > > > catalogues from 1879 - 1908, and may give an indication of resistance to > > > pests and disease, and thus eventual hardiness, if combined with > evidence on > > > parentage for that hybrid. This data could also be used as an aid to > > > identify un-named forms, as graphs can easily be prepared and the > evidence > > > collated. > > > > > > Getting back to viruses. It is obvious for in general, if we can't cure > the > > > plants, we must kill them. However there is a case whereby we are > condemning > > > plants to possibly extinction by killing them. Alberto mentions national > > > collections and specifically, the Canna collection. To answer this, one > must > > > firstly consider the plants importance, its rarity, its place within the > > > garden, potential vectors of viruses in the local vacinity, the > management > > > of these vectors, and the risk of spread to other plants by mechanical > means > > > (by human or leaf contact), and of course correct quaranteen proceedures > > > when plants enter collections of this type. But please don't condemn me > for > > > my honesty when I believe there is a case for conserving plants with > virus, > > > and yes there is a very good case for this to be done. > > > > > > We have to look at the types of viruses that our plants may have, their > > > symptoms, the vectors in each specific case, their ease of tramsmittion, > and > > > how virulent the viruses are. It is very important that when talking > about > > > conservation issues and viruses, that we do not generalise, as each case > is > > > important, and each case must be considered by scientific determination. > > > > > > I have only ever had one really badly infected virused Crocosmia ever > sent > > > to me, and this was destroyed. In conserving old hybrids it is obviously > > > highly probable that many plants contain viruses that can be considered > > > latent, have little or no effect on plant growth, and low risk of > spread. It > > > is threfore for us as an organisation dedicated to bulbs both to > educate, > > > neccessitate, facilitate and promote further scientific study in this > area, > > > and in our own countries. > > > > > > It is also possible that through micropropagation, and by post > > > micropropagation selection, we may eventually be able to distribute > > > certified virus free stocks. > > > > > > Best Wishes, > > > Dave > > > > > > Websites: > > > http://www.theafricangarden.com/ > > > http://www.crocosmiaheritage.com/ > > > > > > Address: > > > David Fenwick > > > NCCPG National Collection of Crocosmia with Chasmanthe and Tulbaghia > > > The African Garden > > > 96 Wasdale Gardens > > > Estover > > > Plymouth > > > Devon > > > England > > > PL6 8TW > > > > > > ----- Original Message ----- > > > From: "Alberto Castillo" <ezeizabotgard@hotmail.com> > > > To: <pbs@lists.ibiblio.org> > > > Sent: Monday, March 03, 2003 2:22 PM > > > Subject: [pbs] Virus in bulbs > > > > > > > Dear Mary Sue: > > > > You are wrong: not all panic at viruses. You > can > > > > still see remarks like "well, it has virus but I like it anyway" too > > > often. > > > > Fortunately there is a growing concern and you have growers like > Diana, > > > Dirk > > > > Wallace and Dash Geoghegan that spend lots of time and money in taking > > > every > > > > precaution to sell healthy material. With time (and no doubt with > more > > > > valuable collections destroyed by viruses) people will learn that it > is a > > > > poor bargain to keep a diseased incurable plant against the rest of > the > > > > collection. We did not invent virus: it is a terrible occurrence that > we > > > can > > > > encounter during our experience as bulb growers. Right now, before our > > > very > > > > noses, one of the most fantastic projects of our time, the assembling > of a > > > > huge Canna collection has been put to an end by this. Most of you know > > > about > > > > the National Collections scheme in England. Well, there was a fabulous > > > > collection of them being assembled and the owner was very happy to > have > > > > found in France 52 cultivars most of which would prove new > introductions > > > (to > > > > the 140 others he was already growing). BUT, in came the Trojan horse! > > > Among > > > > those plants from France some had a virus that rapidly spread to other > so > > > > far healthy ones. That virus was masked by the plants' inherent vigor. > > > When > > > > the owner noticed the appearance of uncommon yellow mottling in many > > > plants > > > > had them tested and it gave bean yellow mosaic and Canna viruses. As > a > > > > result 70 cultivars (yes, 70!) had to be destroyed at once and the > news > > > were > > > > that he had discontinued the project altogether. So remember this > short > > > tale > > > > every time something shows symptoms and you decide to keep it. In my > > > > experience in most cases this is a common plant that sooner or later > you > > > > could replace! > > > > One can never overemphasize the need of a quarantine period . Do > maintain > > > > your newly introduced plants away from your collection for a time (two > > > weeks > > > > at last). Virus symptoms can be masked (there are symptomless and > latent > > > > viruses) but under periods of serious stress (like when you take a > plant > > > > from its "home" and take it somewhere else) symptoms can appear. They > are > > > > more visible (at times ONLY visible) in new growth so watch for the > tips > > > of > > > > new leaves. If they are uniformly green you have many chances that the > > > plant > > > > is healthy. If it shows mottling in a different shade of green be very > > > > worried. If you are not convinced do not let it close to your healthy > > > > collection. For instance if you live in Halifax, send it to Vancouver > for > > > > safety!. > > > > You are right in that there is so little in the > web > > > > on virus symptoms images. In the Ball Guides there are a few images of > > > > viruses in Liliums, Agapanthus, Canna and in a number of dicots. > > > > There is a lot of virused material in the > trade > > > and > > > > several nurseries have a few cultivars of Crocosmia that are terribly > > > > virused. Any comments Dave? In my opinion it was viruses who wiped out > all > > > > those fabulous Crocosmias you mentioned of late. > > > > Regards > > > > Alberto > > > > > > > > > > > > > > > > > > > > > > > > > > > > _________________________________________________________________ > > > > Charla con tus amigos en línea mediante MSN Messenger: > > > > http://messenger.yupimsn.com/ > > > > > > > > _______________________________________________ > > > > pbs mailing list > > > > pbs@lists.ibiblio.org > > > > http://www.pacificbulbsociety.org/list.php > > > > > > --- > > > Outgoing mail is certified Virus Free. > > > Checked by AVG anti-virus system (http://www.grisoft.com/). > > > Version: 6.0.459 / Virus Database: 258 - Release Date: 25/02/03 > > > > > > _______________________________________________ > > > pbs mailing list > > > pbs@lists.ibiblio.org > > > http://www.pacificbulbsociety.org/list.php > > _______________________________________________ > > pbs mailing list > > pbs@lists.ibiblio.org > > http://www.pacificbulbsociety.org/list.php > > --- > Outgoing mail is certified Virus Free. > Checked by AVG anti-virus system (http://www.grisoft.com/). > Version: 6.0.459 / Virus Database: 258 - Release Date: 26/02/03 > > _______________________________________________ > pbs mailing list > pbs@lists.ibiblio.org > http://www.pacificbulbsociety.org/list.php