kazaa81 - 27-8-2005 at 07:40
Hallo to all,
have anyone tried to cultiving lichens?
Any information welcomed!
Thanks at all for help!
E.b.C: spelling
[Edited on 30-8-2005 by chemoleo]
12AX7 - 27-8-2005 at 10:22
No idea. Scrape some off trees/fences/rocks?
Heck, what is it that lichens do in the first place? What interest do you have in them?
Tim
unionised - 27-8-2005 at 11:29
Somebody must know about them or we would run out of litmus paper. On the other hand a quick google for "lichen cultivation" didn't get
far.
kazaa81 - 27-8-2005 at 11:36
What terrain should be suitable? Agar? Water-sucrose? Lichens are a cross between alga and fungus and they do reproduce them via ifes.
Lichens are a good air quality check, because some types grow in a certain air while others not.
my interests in them? firstly for good looking at strange forms of them, also they synthetize certain chemicals.
For who don't know what they are or something i've found this: http://www.earthlife.net/lichens/intro.html
Esplosivo - 27-8-2005 at 22:48
A lichen is composed of two symbiotically related organisms, a fungus and a photosynthetic microorganism, such as a unicellular green alga or a
cyanobacterium. There are three main groups of lichens, namely the crustose (crustlike), foliose (leafy) and fruticose
(shrubby). They are hardy and managed to evolve, survive and colonize most of earths' habitats, including hostile ones such as the antartica
planes. Despite their hardiness, as already mentioned, they succumb to industrial pollution. I had once developed an interest in certain
'species' which accumulate sulfur from the sulfur dioxide in the air.
They may reproduce either by fragmentation of the thallus, that is simply scraping off some part of a lichen and placing it on a 'fertile'
medium will do, or else by soredia, which consists of a few photosynthetic cells surrounded and held together by fungal hyphae, which are
released naturally by the lichen.
Lichens can colonize diverse habitats, ranging from bare rocks to tree barks. They satisfy most of their nutritional requirements from the air and
rainwater, gaining some minerals from their substratum and dust. They are mainly active mainly after a rain, after which they 'dry out'
(<10% water content) and may fall into a dormant state in which they are extremely tollerant to extremes of temperature.
If anyone is interested in growing lichens beware the fact that they typically grow less than or approximately 1cm per year (depending on the
'species' ).
Hope this helps.
Edit: After double checking the relationship between the fungus and the photosynthetic organism is not of the mutually beneficial symbiosis type. The
fungus in the lichen literally squeezes out nutrients from the photosynthetic microorganisms. It was also found out that photosynthetic microorganisms
grow much faster on their own then when associated with the fungus. Thus the relationship is more a type of parasitism by the fungus on the
photosynthetic microorganisms.
[Edited on 28-8-2005 by Esplosivo]
Oxydro - 29-8-2005 at 19:51
I was under the impression that in the harsh environments some lichens grow in, the photosynthetic portion of the organism could not survive without
the aid of the fungus making a protective shield for it. Maybe in terms of nutrients the fungus is a parasite, but overall I think it does contribute.
However its been a while since I looked at such things, and I will humbly accept your version if you tell me I'm wrong 
.
Esplosivo - 29-8-2005 at 23:41
To a certain extent the fungus might be said to provide shelter/protection and maybe create a humid microclimate with an increased availability of
water, but that is it. The fungus reaps most of the benefits, namely the photosynthetic products. It is (in most cases) true that the photosynthetic
organism might not survive in the harsh environment, but this also applies to the fungus which cannot survive without the relation between the two.
Besides, certain relations between organisms are not clear cut, such that they may seem to fall in between two different types of relations.
[Edited on 30-8-2005 by Esplosivo]