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Mycorrhizae - root fungal symbionts · Hydroponics Daily

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  Hi, welcome back to Hydroponics Daily. I'm Dr. Russell Sharp and today we're
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  talking about mycorrhizal fungi.
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  Mycorrhizal. Myco means fungus and rhizor means plant roots.
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  So these are the fungi that live in a symbiotic relationship with plant roots.
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  So the plant gives the fungus 15% of all the carbon it creates through photosynthesis,
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  all the sugars through photosynthesis, 15% goes to the fungus.
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  To equate that, that's the same amount that a plant would normally devote to
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  flowering and fruiting.
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  To give another organism, a completely different species, 15% of its photosynthetic
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  sugars, it must be doing something in return.
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  The mycorrhizal fungi do a lot of things for the plants.
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  The main one is they are extremely important in absorbing phosphorus from the
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  soil or the surrounding environment.
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  However, in hydroponics, that's less of an issue because there's lots of available phosphorus.
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  So what else can they be doing? Well, they can help with stress tolerance.
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  They can help with flooding tolerance and other things like that.
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  And so mycorrhizae are very important for a number of different aspects when
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  it comes to plants. Now, some plants
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  have an absolute requirement for a mycorrhizae or they couldn't live.
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  So an orchid cannot even germinate without a mycorrhizae to provide the early
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  sugars it needs to germinate and nutrition.
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  So the orchid seeds are extremely small, they float in the air like dust and
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  then they land somewhere and hopefully that area has mycorrhizae fungi.
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  And then for the rest of the life of that orchid, it needs mycorrhizae fungi.
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  If you think about an orchid's roots they're extremely thick and they
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  can't absorb they can't get into as much soil as a single-celled
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  fungal strand can so they're extremely
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  important for orchids other plants will form mycorrhizal connections with them
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  and things like pines need a lot of mycorrhizal connections anything in acidic
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  soils and they might form a connection with a number of different species of
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  fungi at once or the same fungus might form a connection with multiple different species of plants.
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  So it's a sort of, what's that film where everyone's blue and there's aliens
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  and they're fighting in space.
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  Go on comment below or getting in
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  touch what is it called is it james cameron film the
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  guy who did titanic anyway it's a bit like that a lot of the
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  pro a lot of the ideas around mycorrhizal fungi avatar that's
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  it that avatar in avatar a lot of the the uh concepts are around mycorrhizal
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  connections and soil connections other plants so about 90 of plants form a mycorrhizal
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  connection with a fungus and then about 10 don't and those 10 include all the
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  brassicas so if you're trying to grow cabbages,
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  it doesn't matter about adding mycorrhizae because they're not going to be important.
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  Proteas, a lot of plants from South Africa don't form mycorrhizae connections
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  and that's thought to be for one of two reasons.
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  One is that the proteas are already living in an extremely phosphorus deficient
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  environment and so they're already exuding lots of chemicals into the soil to
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  absorb phosphorus and so they don't need a fungus to do that.
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  The other reason a lot of plants are thought to evolve not to take on mycorrhizal
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  connections is because a lot of fungi fungal
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  pathogens have an ability to trick the plant into
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  thinking they're mycorrhizal when actually they're a pathogen so if you allow
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  yourself open to good relationships and you're an open plant with you know open
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  arms then and you don't have your defenses up then a pathogen could come in
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  and attack you and pretend to be a mycorrhizal so that's one of the reasons why,
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  scientists believe that certain plants have evolved not to open up themselves
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  to symbiotic relationships.
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  One of the big problems when it comes to mycorrhizal fungi is that you can buy
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  a mycorrhizal product and once it's inoculated the plant, you've got no way
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  of knowing whether it has actually successfully inoculated the plant.
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  It doesn't produce a toadstool or a mushroom or a lesion like mildew would.
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  And so you've just got to believe that it's hoped that it's worked and then
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  the other problem is that even if it has formed a connection and it's.
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  It's doing its thing, it's helping the plant, you might not notice it or you
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  might not think it's significant enough.
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  So imagine you've put mycorrhizae on your plants and it's helped to ward off
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  a disease or a pest, probably a disease more than a pest, but like a root rot.
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  You don't know that that root rot was going to kill your plants.
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  It's a bit like health and safety laws.
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  Everyone complains about health and safety laws because you don't know whether
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  a health and safety law in place at your workplace helps save your life one day.
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  And just like mycorrhizae, you don't know if it helps save your crop.
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  So a lot of people can think they're expensive, nice to haves rather than essentials.
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  And then even sometimes you can get a yield drop if you add mycorrhiza because
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  15% of sugars are going to them.
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  If you're not, you might think, oh, there's a slight yield drop.
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  If the sugars of the plant hadn't formed that connection, could have actually
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  produced more flowers and fruits.
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  Often it's considered a good thing to have though. If you add too much phosphorus
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  fertilizer, it can kill off mycorrhiza.
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  That's because any biocide you apply to the root zone so
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  peroxide something like that will kill mycorrhizae
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  and then there are a number of products on sale that contain
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  mycorrhizae and also additional beneficial microbes the
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  big problem with mycorrhizae products and the reason why we i
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  don't sell them is that they're always dying just
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  like you you're dying now and you've got
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  a population of you know nine billion people
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  a proportion of nine billion people would die every
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  day and if you've got mycorrhizae products
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  on the shelf make sure you're selling them because if
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  you're not selling them they're dying and you don't want
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  to sell somebody a product that's three years old and is dead so try and make
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  sure my top tip if you're a growth shop is or a hydroponic supplier is cycle
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  your your mycorrhizor and your beneficial bacterial products as quickly as you
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  can don't hold massive stocks because they will be dying,
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  Some interesting mycorrhizae include truffles. I'm a big fan of truffles.
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  I'm going to try to convince my family that we should get a truffle dog that
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  we can train to go and find truffles.
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  We live in just south of Leicestershire, and apparently there's a woodland somewhere
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  in Leicestershire that's been seeded with truffles.
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  So my idea is to go out, get some truffles from the supermarket,
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  train this dog for the smell of truffles, and then go out hunting truffles.
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  Other mycorrhizal fungi that are known commonly known fly agaric that hallucinogenic
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  poisonous mushroom the bright red one with the white spots that famous for gnomes and norwegians,
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  they like this fly agaric norwegian i
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  mean we just don't mean norwegian i don't mean norwegian i mean vikings they
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  used to eat it didn't they used to feed it to reindeer or feed
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  it to slaves and then drink the wee and then get hallucinogenic stuff
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  on it and they go raping and pillaging north of
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  england and scotland and things like that so yeah that's
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  my there's some strange mycorrhizal fungi aren't it so there are three main
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  types of mycorrhizal fungi there are the endomycorrhizal fungi which are commonly
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  associated with the plants that live in acidic conditions like the heather family
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  and the orchid family and a lot of herbaceous plants.
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  They're they're particularly important as i said in excess and nutrients for
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  infertile soils The second type are the ectomycorrhizae.
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  These form like a mantle around the plant roots and they're thought to be very
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  good at protecting plants from toxins.
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  And that's one of the areas where mycorrhizae have been explored scientifically
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  is looking at ability to plant to increase the ability of plants to resist toxic and poisonous soils.
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  And then the third type are the vesicular arbuscular mycorrhizae or VAM.
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  And they form a, they live in
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  between the cells in the cortex of the roots okay
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  and they have projections that go
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  within the cells and they're found throughout the world on all different types
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  of plants and they're probably the most primitive form of mycorrhizae so to
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  give you an example an onion root is fairly big and thick and for every centimeter
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  of onion roots there's about 80 centimeters of mycorrhizal strands.
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  So you can think about the increased absorption of the nutrients that that plant
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  can take due to that extra 80 centimeters of growth.
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  Certain plants, when you're cultivating them, mycorrhizae are very, very important.
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  So when you're growing conifers, for example, on a conifer nursery,
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  they always reuse their growing trays because they know they can seed the next
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  seedling with the mycorrhizae.
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  For other crops, you'd never do that because the risk of pathogens and other
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  problems and diseases would be far outweigh the benefits.
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  But for pine trees, the benefits of getting a mycorrhizae connection
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  early on are far outweigh any disadvantages and
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  while mycorrhizal fungi are not a biopesticide they
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  do help the plant resist attack by pest and disease and the number of reports
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  of mycorrhizal preventing a pathogen from infecting a crop are numerous now
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  especially in nutrient film technique commercial growers of like cucumbers and
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  tomatoes really horrible diseases like verticillium wilt,
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  phytophera root rot if you're suffering from root rots then obviously reduce your.
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  If you're growing in like a medium trying to increase
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  aeration but also look at exploring different mycorrhizae
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  okay make sure you've got the right type of mycorrhizae and
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  if you've got any other thoughts about mycorrhizae and then
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  let me know if you've got any good experiences bad experiences we've had
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  both here we we've tried mycorrhizae products
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  that i think some of the contaminants in it and some of the bulking agents have
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  actually impeded the growth of certain grass species we were growing really
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  poor results but then i've seen other really good results on things like bamboo
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  and stuff like that that you wouldn't expect so yeah mycorrhizal that's been
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  hydroponics daily for today.