The following selection is fromMicrobe Science for Gardeners(New Society Publishers , September 2023 ) by Robert Pavlis.courtesy of New Society Publishers
actinomycete are called filiform bacterium , or mildew bacteria . They look and grow like kingdom Fungi but are biologically like to bacterium . They rise hyphae - like togs that consume tolerant organic matter , and they are tolerant of dry land , alkaline grease , and gamey - temperature stipulation . They produce antibiotics such as streptomycin and actinomycin that stop the growth of other microbes . Some of these are useable as commercial drug .
actinomycete tend to be found in decaying organic matter . They can protect plant roots from disease , and in a few cases they cause diseases such as tater scab . Their affinity for eminent temperatures and their ability to break down toughened organic matter makes them an significant contributor in hot composting . These organisms are responsible for the earthy smell of damp , well - aerated soil .
Frankiaare limited actinomycetes that form symbiotic nitrogen - fixing nodules on over two hundred coinage of nonleguminous flora . Most are tree diagram and shrubs such as alders , ocean buckthorn andCasuarinaspecies , many of which are pioneer species that grow in very poor soil .
Why Does Soil Smell So Good?
The earthy smell that climb up after a summer rain is so pleasant that we practice it to scent perfumes . One of the compounds responsible for for this fragrance is geosmin , and its biology in soil is very interesting .
Geosmin is made mostly by an actinomycetes calledStreptomyces , which have a host of other compounds admit the well knownantibiotic streptomycin . Scientists have been wondering for quite some metre why this organism piddle geosmin , and they now havesome insight into this .
Streptomycesgrow mycelium threads through the pore in grime . When they run out of nutrients , it is time to move on , and theyform spores . These spore propagate by flatus and water . As part of the unconscious process of raise spore they also produce geosmin , which draw in springtails .
courtesy of New Society Publishers
Springtails are tiny critters ( hexapod ) that get their name from their ability to hop around like flea , and they have a special attractor for geosmin . As the collembolan rummage through soil looking for geosmin , theStreptomycesspores get attached to the collembolan who then spread them throughout the stain . Springtails are jumping Ubers for actinomycetes.courtesy of New Society Publishers
Microbe Myth: Soil Is an Antidepressant That Makes You Feel Good
You probably see the error - imbue meme that say , “ Soil is an antidepressant . The olfactory sensation ofmycobacterium vacii , a microorganism found in soil , compost and leaf mold , lights up neurotransmitters that unfreeze serotonin , a mood - lifting hormone . ”
Gardeners were straightaway to accept these fact , but I had a closelipped look at the skill behind this . First of all , there is no such being ; however , Mycobacteriumvaccaedoes exist .
5-hydroxytryptamine has been well examine and is know as the “ feel - adept hormone . ” It plays a key character in staving off anxiousness and depression . So , if the smell from microbes in dirt causes higher levels of serotonin , it is quite likely that these olfactory perception make us feel estimable . However , the pleasant smelling of soil is due to geosmin which is made byStreptomycesbacteria , notMycobacteriumvaccae . It is also not linked to serotonin level .
There is no scientific grounds that vulnerability toMycobacteriumvaccaeor geosmin change our serotonin horizontal surface . As with most gardening meme , there is a handful of truth , but most of the message is unseasonable . Do n’t believe horticulture meme .
courtesy of New Society Publishers
