Subject: Boletus edulis culture

From: [email-masked] (Richard Winder)
Date: Thu, 11 May 1995 21:26:13 GMT

Hello,

This is probably not a completely amazing event, but:

For some bizarre reason I made some PDA plate cultures of B. edulis last 
September, and buried them in the 20 C incubator somewhere.  When I ran 
across them today, the cultures had formed substantial (ca. 2-3 cm) lumps 
with fairly well-developed hymenial layers (with tubes) on the upper surface.
Next step- larger volume containers.  If I generate enough of the stuff, I'll
let you know how it tastes.  If it works, I'll trade potatoes for B. edulis
any day...  

We now return you to your regularly-scheduled morel discussion  -RSW

  RICHARD WINDER                    Title: Research Scientist
  Canadian Forest Service           Phone: (604) 363-0773
  Victoria, B.C.                    Internet: [email-masked]

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From: [email-masked] (Steven Carpenter)
Date: 16 May 1995 12:31:59 GMT

Did you place the cultures upside-down?  I am interested in terms of
the position of the tubes you saw in the culture.  If they formed on the
colony surface in a plate that had the surface facing downwards, this would
make sense.  If the tubes formed on a surface that was oriented skyward,
then there may be something genetically interesting.

Are there any yeasts in the culture?  Sometimes native microbes make
it possible for good growth.

-Steve Carpenter
 Cascade Research Associates
   & Abbey Lane Laboratory
 [email-masked]

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From: [email-masked] (Richard Winder)
Date: Wed, 17 May 1995 19:26:01 GMT

In article <[email-masked]>, [email-masked] (Steven Carpenter) 
>it possible for good growth.

The 2 cultures were right-side-up and the tubes formed pointing up. However, 
the tubes are shallow (abortive?) and they lack basidiospores.  There are
primordia present without the tubes as well.  The cultures have been
transferred to wide-mouth tissue cultures with about 2" of PDA in the bottom
in an effort to spur futher development of the primordia.  The primordia
are firm and fleshy, composed of parenchyma-like cells (not hyphae) which
appear to be organized somewhat into tissue layers.  There are no yeast or
bacterial contaminants in the culture I checked microscopically.  The outer 
part of the colonies contains rhizomorphic hyphae that extend about half-way 
to the rim of the Petri dish- the colonies do not colonize the entire plate 
before forming the primordia.  Nutrient diffusion would appear to be occuring,
considering the energy which must have gone into making the primordia.  
During the long (8 mo.) incubation period, the agar lost some water content 
(about 50%), but I cannot say if that happened before or after formation of 
the primordia.  The source for the Potato Dextrose Agar was Difco.  During an 
earlier fruiting of the same patch of B. edulis, I made a deep-beaker culture 
of the fungus using modified Hagem/Modess medium, but the fungus has not done 
anything remarkable for me in that system, other than barely grow.

I just had a sample of B. barowsii (White King Bolete) brought into the lab- 
we've got that one going on PDA now to see what it will do as well.  -RSW

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From: Thomas O'Dell <[email-masked]>
Date: Thu, 18 May 1995 13:21:40 -0700

Have you seen Pantidou's papers from the early 60's?
Can J. Bot. 40:1313
ibid 42:1147
Fertile sporocarps of several boletes have been obtained in culture 
(though i don't think it has been repeated and I'm sure that edulis was 
not one of te species, maybe not even Boletus spp. but other bolete genera).
By the way, if that is really B. barrowsii that would probably be the 
first record for the species outside of the southwest... was there 
Ponderosa (or other) pine in the vicinity? (it may be pine specific).
It could be a pale edulis or B. pinicola...
Cheers!
 
[email-masked]

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From: [email-masked] (Richard Winder)
Date: Sun, 21 May 1995 01:39:55 GMT

In article <Pine.A32.3.91j.950518131006.124603B-100000@
>Have you seen Pantidou's papers from the early 60's?

Yes.

>not one of te species, maybe not even Boletus spp. but other bolete genera).

B. rubinellus, mostly, because of it's typically small size.
That system appears to have been used by several researchers.  B. edulis has 
been reported cultured in Poland, but I have not run across any replications
of that work by other researchers- I'd like to hear about them if someone
has done that kind of thing.  A few others in the boletaceae have also
been mentioned.  I suspect that many times B. edulis makes it to the kitchen 
before it gets into the lab.  As I said in my original post, this is not 
a completely unprecedented thing.  I think that the interesting point is 
that the primordia formed in a system as small as a parafilm-sealed Petri
dish (with appropriate lag time & room temp.), and with a medium as simple 
as non-acidified PDA.

>It could be a pale edulis or B. pinicola...

B. barrowsii is also said to associate with oak in California.  The caps 
were very white, not appearing to be merely faded or paler.  Cap cuticles 
were not all that thick, and were non-viscid.  Morphology similar to B. 
edulis, but a bit smaller.  There were no ponderosa pine nearby- they were 
in a Garry oak (Quercus garryana) meadow.  The late spring fruiting was a 
bit of a surpize, and I know that there are supposed to be some pale B. 
edulis forms kicking around up here- now that you have me doubting what's 
what, we'll have to take another look at the samples to be certain.

Its great to see so many people out there keen to know about boletes- I'm
certainly not a bolete expert, but I would definitely like to learn more.
Thanks for your post.  -RSW