paphioboy
hehehe...
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This was brought up in the vermicompost thread and I think it deserves a thread of its own, seeing that many people are interested. The use of effective microorganisms (EM) to help orchid growth is interesting because I think what you add is more important than how much. Mainly because most of the epiphytic species do not have a symbiotic relationship with many of the soil-dwelling fungi. Most epiphyte species, in fact, are symbiotic with certain isolates of potentially pathogenic fungi, including Rhizoctonia, Fusarium and Pythium. There are many papers on this, you can Google 'Orchid mycorrhiza'. In contrast, the more common mycorrhizas or beneficial fungi for non-orchid temperate terrestrial plants belong to the Glomerales and Gigasporaceae. Many EM products tend to contain these fungi or other supposedly biocontrol agent species that help protect the plant, like Trichoderma (a known parasite on other fungi).
For the slipper alliance, it is known that most of the naturally-associated fungi belong to the Tulasnella/Epulorhiza and Ceratobasidium group, some of which are unculturable. Epulorhiza is strongly-associated with Paphs. If you add in a different fungus, the additive could in fact be competing with the naturally occurring fungi, and could be detrimental to plant health. Several people here who have used EM products say they get detrimental effects like leaf-spotting, which could be due to use of an incompatible microbe. Interesting to note, one of the papers below (Shefferson 2007) states that some widely-occurring Cypripedium species (calceolus) have a more specific relationship with the symbiotic fungi, whereas other cyp species which have a more narrow habitat (formosanum) are more generalist in their preference of fungal partners.
Some references for those interested in orchid mycorrhiza:
http://www.academia.edu/458826/Studi...nachal_Pradesh
Fungus in Paph thaianum roots:
http://www.scirp.org/journal/PaperDo...?paperID=22189
Fungus in Parvisepalum (no full text, but you get the gist in the abstract):
http://english.kib.cas.cn/rh/rp/2011...321_66672.html
Evolution of fungi in Cypripedium:
http://nature.berkeley.edu/brunslab/...ferson2007.pdf
For the slipper alliance, it is known that most of the naturally-associated fungi belong to the Tulasnella/Epulorhiza and Ceratobasidium group, some of which are unculturable. Epulorhiza is strongly-associated with Paphs. If you add in a different fungus, the additive could in fact be competing with the naturally occurring fungi, and could be detrimental to plant health. Several people here who have used EM products say they get detrimental effects like leaf-spotting, which could be due to use of an incompatible microbe. Interesting to note, one of the papers below (Shefferson 2007) states that some widely-occurring Cypripedium species (calceolus) have a more specific relationship with the symbiotic fungi, whereas other cyp species which have a more narrow habitat (formosanum) are more generalist in their preference of fungal partners.
Some references for those interested in orchid mycorrhiza:
http://www.academia.edu/458826/Studi...nachal_Pradesh
Fungus in Paph thaianum roots:
http://www.scirp.org/journal/PaperDo...?paperID=22189
Fungus in Parvisepalum (no full text, but you get the gist in the abstract):
http://english.kib.cas.cn/rh/rp/2011...321_66672.html
Evolution of fungi in Cypripedium:
http://nature.berkeley.edu/brunslab/...ferson2007.pdf