Strigolactones: The Unmasking of a New Branching Hormone
Strigolactones are a group of terpenoid lactones that act as a host-derived signal in the rhizosphere communication of plants with arbuscular mycorrhiza and root weeds. They also occur as endogenous plant hormones regulating shoot branching in plants. All natural strigolactones contain a tricyclic ring system connected to a butenolide via an enol ether bridge. Most of the germination stimulants identified so far are strigolactones.
Shoot branches grow from axillary buds that arise in leaf axils. Auxin and cytokinin have long been known to be important plant hormones involved in regulating the outgrowth of axillary buds into branches. Recently, thanks to the use of branching mutants in several species, we now know the identity of a third hormone group, strigolactones, involved in this process.
http://5e.plantphys.net/article.php?ch=&id=486
Dizzlekush says:
Strigolactones initiate germination of AM, increase mitochondrial activity and density of AM, increase cell proliferation of AM (growth), and promote pre-symbiotic branching of AM. This naturally occurs in the rhizosphere as a/the plant starts lacking nitrogen and/or phosphorous and exudes specific strigolactones into the rhizosphere, or when certain environmental cues happen. The entire process usually unfurls in a 4-6 week period. One could essentially sidestep this whole 4-6 week natural forming of symbiosis by doing this process yourself, as i previously mentioned, saving your plants 4-6 weeks of work/waiting...
Again this is all just theory, im not aware of strigolactones ever being concentrated or synthesized and utilized in any sort of experimentation. We're pretty slow when it comes to strigolactone research ATM. We've known about them for over 15 years and have thought they were detrimental to plant growth for more than half the time we've been aware of them (because they were exuded by witches weed). Only ~7 years ago we discovered that they had beneficial aspects , and only 4 years ago did we find out that they are one of the essential groups of phytohormones in all (terrestrial at least) plants.
Master hormone controls plant growth
A single hormone co-ordinates how a plant grows in response to the environment, researchers have found.
Plant molecular biologist Dr Phil Brewer, of the University of Queensland, and colleagues, report their findings about a chemical called strigolactone
Stem thickening
Brewer and colleages have found that when strigolactone levels are high, not only does this stop buds from turning into branches, but it also thickens up the main stem.
This makes sure that a plant growing tall to reach the light, also has the structural strength to do so.
"We now think that this is a hormone that co-ordinates a response for the whole plant," says Brewer. "It's not just about the branching, it's also about other parts of the plant. It's about optimising its growth."
He says that for many years, scientists thought the thickening of stems was controlled by a chemical called auxin, but these latest findings challenge this.
"This is a breakthrough for us because it shows that auxin works through strigolactones to do this job," says Brewer. "It's a big change in the dogma of the field."
Brewer says he and collaborators are also finding strigolactone influences other parts of the plant too.
When nutrient levels are low, strigolactone levels rise and this stimulates production of root hairs and beneficial mycorrhizal fungi, which both help increase uptake of nutrients.
On the downside, some parasitic weeds have hijacked this system, says Brewer.
Strigolactone exuded from the plant roots signals to the seeds of these weeds its time to germinate and invade the nearby host plant.
Brewer says it's possible that strigolactone could be fed to trees that are being grown for timber to make them grow strong, tall and straight.
"It would also potentially make the trees more efficient at taking up nutrients,
http://www.abc.net.au/science/articles/2011/11/29/3378297.htm
Strigolactones fine-tune the root system
https://www.google.com/url?sa=t&rct...=D66T-r2Atjnm6gAOSouLYw&bvm=bv.57799294,d.b2I
Strigolactones are a group of terpenoid lactones that act as a host-derived signal in the rhizosphere communication of plants with arbuscular mycorrhiza and root weeds. They also occur as endogenous plant hormones regulating shoot branching in plants. All natural strigolactones contain a tricyclic ring system connected to a butenolide via an enol ether bridge. Most of the germination stimulants identified so far are strigolactones.
Shoot branches grow from axillary buds that arise in leaf axils. Auxin and cytokinin have long been known to be important plant hormones involved in regulating the outgrowth of axillary buds into branches. Recently, thanks to the use of branching mutants in several species, we now know the identity of a third hormone group, strigolactones, involved in this process.
http://5e.plantphys.net/article.php?ch=&id=486
Dizzlekush says:
Strigolactones initiate germination of AM, increase mitochondrial activity and density of AM, increase cell proliferation of AM (growth), and promote pre-symbiotic branching of AM. This naturally occurs in the rhizosphere as a/the plant starts lacking nitrogen and/or phosphorous and exudes specific strigolactones into the rhizosphere, or when certain environmental cues happen. The entire process usually unfurls in a 4-6 week period. One could essentially sidestep this whole 4-6 week natural forming of symbiosis by doing this process yourself, as i previously mentioned, saving your plants 4-6 weeks of work/waiting...
Again this is all just theory, im not aware of strigolactones ever being concentrated or synthesized and utilized in any sort of experimentation. We're pretty slow when it comes to strigolactone research ATM. We've known about them for over 15 years and have thought they were detrimental to plant growth for more than half the time we've been aware of them (because they were exuded by witches weed). Only ~7 years ago we discovered that they had beneficial aspects , and only 4 years ago did we find out that they are one of the essential groups of phytohormones in all (terrestrial at least) plants.
Master hormone controls plant growth
A single hormone co-ordinates how a plant grows in response to the environment, researchers have found.
Plant molecular biologist Dr Phil Brewer, of the University of Queensland, and colleagues, report their findings about a chemical called strigolactone
Stem thickening
Brewer and colleages have found that when strigolactone levels are high, not only does this stop buds from turning into branches, but it also thickens up the main stem.
This makes sure that a plant growing tall to reach the light, also has the structural strength to do so.
"We now think that this is a hormone that co-ordinates a response for the whole plant," says Brewer. "It's not just about the branching, it's also about other parts of the plant. It's about optimising its growth."
He says that for many years, scientists thought the thickening of stems was controlled by a chemical called auxin, but these latest findings challenge this.
"This is a breakthrough for us because it shows that auxin works through strigolactones to do this job," says Brewer. "It's a big change in the dogma of the field."
Brewer says he and collaborators are also finding strigolactone influences other parts of the plant too.
When nutrient levels are low, strigolactone levels rise and this stimulates production of root hairs and beneficial mycorrhizal fungi, which both help increase uptake of nutrients.
On the downside, some parasitic weeds have hijacked this system, says Brewer.
Strigolactone exuded from the plant roots signals to the seeds of these weeds its time to germinate and invade the nearby host plant.
Brewer says it's possible that strigolactone could be fed to trees that are being grown for timber to make them grow strong, tall and straight.
"It would also potentially make the trees more efficient at taking up nutrients,
http://www.abc.net.au/science/articles/2011/11/29/3378297.htm
Strigolactones fine-tune the root system
https://www.google.com/url?sa=t&rct...=D66T-r2Atjnm6gAOSouLYw&bvm=bv.57799294,d.b2I
