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  Anthurium blight
From: ExoticRainforest <Steve at exoticrainforest.com> on 2010.01.11 at 11:54:00(20459)
A warning from our friend LelandMiyano from information originating from botanist David Scherberich.

There is now a very bad Anthurium blightwhich may be spreading. At least two gardens in France have hadto deal with this one which has no cure. The one that is really badis Xanthomonas campestris pv. dieffenbachiae whichcauses the leaf margins to turn yellow and all the leaves to drop. Iwould suggest you be very careful about buying new Anthuriumright now! This has the potential to kill an entire collection.

Some species appear resistant but others spread it quickly. Somecommercial growers in Hawaii lost almost entire crops of ornamental Anthurium(the kind you buy in the store) so be very careful about buying any Anthuriumin a local nursery or discount store!

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1392979/

Any of you that are knowledgeable about this blight please pass alongwhat you know.

Steve

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From: "Marek Argent" <abri1973 at wp.pl> on 2010.01.12 at 08:38:37(20462)




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From: George Yao <geoyao at gmail.com> on 2010.01.14 at 10:38:48(20472)
Hello Steve,

I asked a horticultural consultant about this and he informed me that Anthurium blight has existed in Hawaii for three decades already. According to him, the solution prescribed of using antibiotic is not effective. He asserted that "Bacterial Disease is a systems defect. They will need to ovehaul their production system to solve the problem." Additionally, he maintained that "Holland never had that problem because of the Dutch integrated agricultural approach." He informed me that recently he was hired to solve that problem in Jakarta and he claimed that "Problem now solved. No more bacterial infections."


George Yao

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From: agrsuw at ku.ac.th on 2010.01.15 at 00:47:41(20476)
Dear all,

I strongly agree with J. People should not be discouraged to purchase and
enjoy anthuriums because of the disease.

The blight has been with us for a very long time. It will spread only if
the condition (humidity and air movement) is right.

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From: ExoticRainforest <Steve at ExoticRainforest.com> on 2010.01.15 at 11:35:09(20478)
Thanks Jay. My knowledge of thisstuff is very limited but it did concern me once I began to read someof the info on the internet. We see lots of poorly grown ornamental Anthuriumin some of our local stores, often showing signs of what may bedisease. I have a relative that is a district manager for a largeretailer and he says they throw away lots of plants as a result. Ijust wouldn't want anyone to get the stuff in a prized collection.

Thanks again for the info.

Steve

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From: Jay Vannini <heloderma5 at hotmail.com> on 2010.01.16 at 08:54:56(20482)
Steve:
 
Glad to have been of service.
 
Several clarifications appear in order.
 
- IMO, it is EXTREMELY unlikely that anthurium blight is not already in everyone's exotic aroid collection who is reading this, either manifest or latent.
 
- From old lab work I know that I have had at least three separate introductions into my own, from South Florida nurseries (1999-2000), from a domestic anthurium cut flower source (1998-2000), and from a commercial supplier in South America (this was diagnosed from tissue collected at port of entry by our Ag Ministry lab in 2003...at that time Xanthomonas campestris-positive did not require destruction of the plants so they were waived. Needless to say, I quarantined the blazes out of this and all subsequent commercial imports through 2006. Following ratification of DR-CAFTA we are now under the regional one size fits all rule...these plants would be incinerated if this import occurred today). 
 
- Based on the protocol I outlined earlier, I grow many flawless, very blight-sensitive Anthurium spp. in close proximity to other plants with minor blight halos evident on leaf edges and have images to prove it.
 
- For George Yao's benefit, what I outlined in response to your initial posting IS an IPM-inspired protocol for control of this blight in private and public collections.
 
- Commercial growers have a vastly different set of challenges and require a very different protocol for blight management and require a somewhat different approach (see below).
 
- I have the short form product data sheet for Agri-mycin formulation that I use (manufactured at Pfizer's Toluca plant in México) before me. A correction to an earlier statement I made...it is in fact 15% streptomycin sulfate and 1.5% oxytetracycline + inert balance, not 17% streptomycin as I wrote. In any event, in free translation the sheet reads that the product is "recommended" for "control of the following diseases": "...bacterias caused by the genera Xanthomonas, Erwinia and Pseudomonas" in the "following crops": "Ornamentals"...Philodendron, Dieffenbachia, Aglaonema."
 
- At yesterday's market close, Pfizer, Inc. market cap was almost US$ 160 BILLION.
 
- If, say, it were revealed that Pfizer, Inc.'s ag-chem division was making manifestly false claims regarding the efficacy of one of their mainstream products then, say, a well-heeled large ornamental plant grower might be tempted to sue their pants (and big pants they are!) off.
 
- Agri-mycin can provide very effective suppression (not cure) of anthurium blight in COLLECTIONS OF ORNAMENTALS when used properly in conjunction with a broader IPM-inspired protocol. It is NOT a panacea nor a silver bullet to eradicate anthurium blight and neither I (nor Pfizer) would ever claim that it is. However, it certainly can provide suppression to a point where healthy, well-grown plants can prosper with it latent in their environments. My own fairly large blight-susceptible aroid collection, plus several published sources, proves it.
 
- IMO, and as diplomatically-put as possible; anyone who claims otherwise doesn't know what he/she doesn't know.
 
- If a given grower blithely continues to challenge their blight-susceptible tropical aroids with environmental (note: IME, lousy water quality aggravates anthurium blight in delicate plants for certain) or management issues, this critter will ultimately (often in short order) decimate all those vulnerable plants and nothing short of Divine Intervention will save them. Don't waste your money on ag-chem if you are not willing to practice clean culture - it won't really help.
 
Thus, from a hobbyists' perspective, successful management of this nasty pathogen requires a certain mindset and quite a bit of discipline with regard to handling and triage of visibly-affected plants. Believe me, it works. Conversely, commercial growers have, in the past, been faced with no other economically viable option other than having to destroy their entire blight-susceptible inventory and start afresh with new cultivation protocols and blight-resistant stock from micropropagation. This also works, but at a very steep price.
 
All those here who are willing to properly dispose of the entirety of their exotic aroid collections just because they contain some suspicious-looking or blight-diagnosed rare plants and start all over with those handsome (the colors!!!) tissue-cultured, mass-produced, PATENTED (no unauthorized asexual propagation, folks) anthuriums, aglaonemas, alocasias and philodendrons, please hold up your hands.
 
Didin't think so...  
 
J
 
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From: Jay Vannini <heloderma5 at hotmail.com> on 2010.01.16 at 10:37:58(20483)

One final clarification on control of aroid blight for those who did not catch this at the end of my first response...even at approved rates and concentrations Agri-mycin can be briefly but extremely phytotoxic to some ornamental aroids, esp. some specific anthurium spp. and cut flower types (the reason why it is not labeled for use on this genus in this region) and can burn leaves severely. For commercial growers this can be a deal-breaker for obvious reasons, but for hobbyists and BGs it is infinitely preferable to have burned leaves on your prized giant Anthurium superbum or A. veitchii for a year or so than to watch it succumb to aroid blight.
 
An old paper, but authoritative source: http://facultystaff.vwc.edu/~presslar/CultivatedAnthurium/PDF-Lib/BacterialBlightControl-No14.pdf The heads-up on not making this an everyday standby echos Surawit's earlier cautionary note about breeding blight resistance to antibiotics. I agree.
 

Date: Fri, 15 Jan 2010 13:35:09 -0600
From: Steve@exoticrainforest.com
To: aroid-l@gizmoworks.com
Subject: [Aroid-l] Anthurium blight

Thanks Jay.  My knowledge of this stuff is very limited but it did concern me once I began to read some of the info on the internet.  We see lots of poorly grown ornamental Anthurium in some of our local stores, often showing signs of what may be disease.  I have a relative that is a district manager for a large retailer and he says they throw away lots of plants as a result.  I just wouldn't want anyone to get the stuff in a prized collection.

Thanks again for the info.

Steve

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From: "Famille FERRY" <jpcferry2 at wanadoo.fr> on 2010.01.17 at 09:43:07(20484)
Dear aroiders ,

I also have this problem on some tasks oily Anthuriums.
Once a year, in autumn, I am treated with Bordeaux mixture.
The problem has stabilized.

Bordeaux mixture is obtained by mixing copper sulfate and hydrated lime well in water. This mixture should never be in a container of iron.
1.Within first container, dissolve 80 grams of lime in 5 liters of water.
2.If a second container, dissolve 150 grams of copper sulfate, also in 5 lites of water.
3.Mélangez both mixtures .

The best ,

Genevičve Ferry ,

Nancy Botanical Garden

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From: ExoticRainforest <Steve at ExoticRainforest.com> on 2010.01.17 at 13:08:33(20485)
Good info! Thanks!

Steve

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