Nova doença de Phalaenopsis vindos de Taiwan
Autor: Nossas Orquídeas | Publicado: 2012-01-16T07:34:00-08:00

Nova doença bacteriana em Phalaenopsis com alta  resistência que ataca inclusive outras orquídeas. &nbsp; Hello  Oliver,What  you are describing sounds a lot to me like a Taiwanese diseasecalled  Taiwan Yellows. The Taiwanese have been using high levels ofantibiotics  for years on these plants in their giant production housesto  control Psedomonas bacteria. They have used these antibiotics so muchthat  they have created a super strain of the bacteria which althoughlatent  when they ship their plants to foreign countries usually eruptson  infected plants in a month or two after shipping. Often the cooltemperatures  in countered in shipping in containers by sea and thecooler  environs of finishing greenhouses in say North America and Europeoften  portend the onset of the bacterial infection. We have had manycustomers  come in with these mass produced plants from Some of the BigBox  stores wanting us to diagnose the problem. We simply don't allowthose  plants in our retail area anymore due to the virulent nature ofthis  bacteria.My  own personal experience goes back to the world orchid conference inMiami  in January of 2008. I went there to look for plants to add to mybreeding  stock and had purchased 10 Phal. bellina coerulea from aTaiwanese  vendor. I brought them back to Minnesota, potted them up andput  them on the bench to grow and flower out in the coming summer. Afterabout  2 or 3 weeks I lost one of the plants and then another etc. everyweek  or two until I started noticing that in the same area radiating inan  outward circle more and more of my plants were becoming infected.This  went on until early summer and the circle of death was enlarging astime  went on. I had thrown out over $50.000 worth of plants and not justPhalaenopsis  but any other species as well. I tried using everyfungicide  and bactericide I could find including Physan 20, Phyton 27,Cleary's  and others and could not stop the spread. I had to get theUniversity  of Minnesota involved and they looked at the cell tissue andfound  that there was the highest concentration of the bacteria in a cellthat  they had ever seen. Their suggestion was to destroy every plant inthe  greenhouse and then to bleach all the greenhouse surfaces includingwalls,  benches, floors glazing everything!After  collecting orchids for 30 years I could not &nbsp;imagine destroyingplants  that could simply not be replaced. I just happened to read in agreenhouse  trade magazine about a new product that was made of dimethylammonium  chloride laced with urea that would go inside the plant tissuesand  kill bacteria, fungal and even virus from within but yet stillpreserve  the nucleus of the cell. I was ready to try anything so Icalled  the company that made it and they sent me some samples to try.After  1 application the disease was halted. I applied the product 2 moretimes  at 2 weeks apart and managed to clean the bacteria right out ofthe  plant.Yellow leaves, slowly over a period of 2 or 3 months regainedtheir  green look and what amazed me more was the cleaning of certainorchid  viruses right out of Stud phalaenopsis that I knew had viurs butkept  anyway for historical purposes.One  of the symptoms can be a yellow watery filled leaf. The diseasespreads  through water and can swim across benches and up walls as wellas  across the floor. I know of folks in Canada and the US who have losttheir  whole collection to this disease some were commercial growers andothers  were hobbyists.Not  all Taiwanese plants or growers have this problem but I do believethat  Since some countries like the USA or other European countriesstarted  allowing Taiwanese Phalaenopsis to be imported with the Sphagnummoss  and pots they were originally growing in the problem has onlygotten  worse. Bare root plants didnt seem to be as much as a problembefore.  I have also personally seen Dendrobium weevils hiding in thesphagnum  moss and then climb up the flower stems to chew on the flowers.Us  growers were asked by the U.S.D.A. for comments and opinions aboutallowing  plants from Taiwan in to the US with the potting mix (moss)still  on the roots and in pot. US growers all voiced their opposition tothis  idea but we were brushed aside as what this was really about was areciprocal  trade deal made during the Clinton era. The Hawaiian growerstried  to sue the government but they made a mistake and sued them inWashington  D.C. where things have a habit of being tilted in thegoverment's  favor. It would have been better to sue in Hawaii. TheHawaiians  then decided to impose a ban on Plants arriving in Hawaii inMoss  and in pot but the USDA forced their hand and told them theycouldn't  impose a State rule over a Federal rule regarding nationalagricultural  commerce.I  would suggest that any serious hobbyist or commercial grower eitherisolate  new plants for a time of treat them and isolate them to preventa  tragic loss of beloved stock that is sometimes irreplaceable.--Best  wis*Orchids  Limited4630  Fernbrook Ln NPlymouth,  MN 55446 USATOLL  FREE 1-800-669-6006LOCAL  763-559-6425FAX  763-557-6956www.orchidweb.comorchids@orchidweb.com*