Phytophtora

Slippertalk Orchid Forum

Help Support Slippertalk Orchid Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Joined
Dec 16, 2009
Messages
3,726
Reaction score
3,914
I know this fungus does not hurt paphs but I would like to ask for your advice.
I nave grown catts for about 20 years and paphs for 6 years. My catts were happy always, paps were suffering mostly were died by erwinia. I heard a tip about using much CA and Mg. Erwinia hates them. So I began to use many limestone in mix+mg and ca solution in water and erwinia dramatically disappeared without chemicals!!!
But I have no idea with phytophtora. Catts' new growth begins to turn black and soft at apex and die within few days. Please help me: what does phytophtora hate???????
 
I know this fungus does not hurt paphs but I would like to ask for your advice.
I nave grown catts for about 20 years and paphs for 6 years. My catts were happy always, paps were suffering mostly were died by erwinia. I heard a tip about using much CA and Mg. Erwinia hates them. So I began to use many limestone in mix+mg and ca solution in water and erwinia dramatically disappeared without chemicals!!!
But I have no idea with phytophtora. Catts' new growth begins to turn black and soft at apex and die within few days. Please help me: what does phytophtora hate???????

Actually phytophthora is one of the most important diseases of paphs, second only to fusarium and pythium...

You most likely did not see erwinia on paphs, but pythium, there are pictures here:

http://www.hark-orchideen.de/Pflanzenschutz/Phythium/bilder.php?lang=en&navID=99

For control of phytophthora and pythium, usually metalaxyl + fosetyl-Al will do it, if not, you have to use dimetomorph. Phytophthora does not hate anything specific, though proper media pH will lower the risks.

When the catt new growths turns black and die, that can be either a severe calcium deficiency, especially if the rot does not attack the rhizome. Otherwise, it is most likely fusarium...
 
Some people I know have treated phytophthora with a little bit of Amoxil antibiotic on the problematic area. But I do not know if it is ok to use such things, as it might lead to more resistant bacterial strains.
 
phytophthora

Black rot, stem rot, root rot cause by fungi = Phytophthora palmivora, metalaxyl + fosetyl-Al alternate with dimethomorph is a smart choice, because dimethomorph show no cross resistant to metalaxyl a member of phenylamide group(benalaxyl, oxadixyl),but not Pythium spp..

Soft rot cause by bacteria = Erwinia carotovora, Erwinia chrysanthemi, the different is a stong and bad smell.Antibiotic (streptomycin, oxytetracyclin etc.) is recommend but beware resistant and phytotoxic.

Plus Ca and Mg in fertilizer program is a better way to make plant grow vigor and healthy in long run,not only resist to pest but also good quality in all parts.
 
Black rot,

Plus Ca and Mg in fertilizer program is a better way to make plant grow vigor and healthy in long run,not only resist to pest but also good quality in all parts.

Are you referring to any work by Dr Easterwood? or do you have some orchid specific information?
 
phytophthora

The data Pest and Diseases from Department of agriculture (DOA),Ministry of Agriculture for Dendrobium cut flower.

Chemical data base on The Pesticide Manual by BCPC.org and Farm Chemical Handbook by Meister Publishing Company.

Application method from our experience, more than thirty years in agrochemical field,and
www.irac-online.org
www.frac.info
www.hracglobal.com
www.rrac.info
www.accuweather.com
www.fertilizer101.org

Now I'm do one stop service free of charge on soil, water, fertilizer, pest, disease in all crop.
 
phytophthora

RICK, can you forward me, detail of Dr. Easterwood.

For your information: last ten years, I'm set up a small business about fertilizer,secondary-micronutrient,sea weed,first I'm start with fertilizer manufacture in Canada, I found that Floricultura in Holland (orchid and curcuma)use it (I'm visit there on Floriade 2002),orchid fram in Taiwan, Singapore also use).Secondary-micronutrient from England,Sea weed from Algea productuer Norway and Acadian Canada.

The key word "Increase Quality, Yield Increase" by using Sugar content in cell sap to declare and compare.Sampling from the same part of sample, read it by hand refractometer.(data from Agrimart USA product technical information handbook claim that base on MSU research 30 years ago,few years ago technician from Australia show me the same paper.)

Example;
Shiraz after 1 year application the yield increase 1 time, sugar content increase from 22 to 29 brix.

Fresh produce vegetable for export ; Okra, Asparagus, baby corn, Sweet pea, Edamame etc. increase sugar content, shelf life, taste.

Orchid; dendrobium-mokara cut flower, pot plant got the same.

Now I'm recommend my grower to formulate fertilizer by themselves using the proportion of Nitrogen form the same as manufacture in Canada do.After prove it for many years, today they need top quality fertilizer,because we face the problem of climatic change,many rain, sunny day decrease from 200 to 150 days/year.

It enough or not for your consideration. many.....many THANKS.
 
RICK, can you forward me, detail of Dr. Easterwood.

Private Message me your email address, so that I can forward the article.

I don't have the link anymore, and the pdf is too big to post on this site.

I've been using a seaweed extract for about 6 months now. It has almost no NPK to it, but full of micronutrients and organics.
 
phytophthora

seaweed: I'm didn't know you choose what formulation, concentration.

in my home i recommend my grower DIY : water 60 liters mix seaweed soluble powder 20 kg.,separate in small amount agitate to good soluble,mix Nicspray 2 kg.(secondary-micronutrient), mix Nipasol-M 100 gm.(preservative),water to reach 100 liters.

secondary-micronutrient: DIY use sulphate salt 5 hydrate or some EDTA depend on material found in local.
 

Latest posts

Back
Top