seed germination

[ian mcdonald]

Has anyone tried using mycorrhizal fungus as an aid to seed germination, if so, what were the results?

[Maggi Young]

Hello Ian,
Mixed results reported in the past from Forumists- but this thread http://www.srgc.net/forum/index.php?topic=6697.msg187796#msg187796
has some handy links to suppliers - some posts are copied below -

........... Rootgrow is a Mycorrhizal fungi which is something different to Trichoderma harzianum. I tried the Mycorrhizal fungi for 14 months on 10 experimental Clivia seedlings. Five seedlings were planted with Mycorrhiza mixed in the growing medium and five seedlings were planted without Mycorrhiza. After 14 months I took all the seedlings out of their pots and I could not notice any difference in root growth or leaf growth between the 10 plants.

Trialling is made more difficult by the lack of a standard product available worldwide.  I think there are quite a few forumists risking our precious snowdrops with the version of Trichoderma that is available in the UK, which is something called "Canna Aktrivator".  At www.canna.com Canna describe themselves thus: "We are the Dutch experts and internationally recognised world wide leader in intelligent plant technologies for cultivating your favourite plants in cocoponics, hydroponics and soil."  We don't know if this is the same formulation as the New Zealand product, "Rootmate" or the product sold in South Africa.

A couple of us wrote to Rootgrow and got this helpful reply today...

You both enquired about rootgrow and Trichoderma on the same day, which was very unusual for us so i hope you don't mind me combining your email response.

rootgrow contains UK origin mycorrhizal fungi, a combination of arbsucular mycorrhizal fungi and ectomycorrhizal fungi, it does not contain Trichoderma.

It is likely the two products are compatible, however i need to clarify that point.

With a Trichoderma product it maybe easier to think of it as a foliar fungicide, i.e. you spray it onto leaves and the soil surface.

Trichoderma is a myco-parasite, a parasite of fungi and has been known to help control damping off or pythium in seedlings and botrytis (Gray Mould) in some crops.

Mycorrhizal fungi exhibit a symbiotic relationship with their host plant, they exist attached to plant roots living underground where they source water and nutrients and feed them to the host plant.

As a rule of thumb, use Mycorrhiza when planting into soil on the plant roots on mature plants that have left propagation, use Trichoderma in container growing, including seed growing and propagation of young plants. You can try introducing Mycorrhiza in propagation but due to artificial substrates and restricted root development the benefits are usually small, mycorrhiza really benefit plants when planted into soil.

If you were to inoculate young plants with mycorrhiza and then do a deep soil drench of Trichoderma (not just a light foliar spray but soaking the compost, which would be very expensive) then there maybe some antagonism between Trichoderma and mycorrhiza i.e. the Trichoderma would start feeding off the Mycorrhiza.

I do know of some Dutch scientists that have however found no antagonism, in fact the two organisms work well together, that may have been down to a unique strain of Trichoderma. It is here that we are right on the edge of science and what we know, it will probably be a decade or so before we understand these interactions better. As far as I recall on my studies on Trichoderma we hadn't even properly identified Trichoderma to the Species level, they were known as Species Aggregates.

If you wish to try using the products in conjunction please follow the above advice, there should be no detrimental effects to the plants as the likely negative outcome would be the Trichoderma just consumes the Mycorrhiza, however initially and from a common sense point of view try it on a small number of low value plants and see how you get on.

Regards

Mark

--

Mark Mackie
Sales & Marketing Director

M 07834 515 313

PlantWorks UK
1-19 Innovation Buildings
Kent Science Park
Sittingbourne
Kent
ME9 8HL
T 01795 411527
F 01795 411529
E info@plantworksuk.co.uk
www.friendlyfungi.co.uk

From casual discussion with friends recently it seems that quite a few are using Rootgrow and finding it useful - certainly not doing any harm - which is often half the battle!

[Maggi Young]

A reminder of the  useful info at  the  website  of the  Ontario Rock Garden Society -
https://onrockgarden.com/index.php/germination-guide/germination-guide

[Véronique Macrelle]

oh this is a topic that fascinates me!

 Moreover, I always put a small part of my garden soil in the seedling medium, to 'sow' any soil symbiosis, and I never sterilize.

I want to take the rhizosphere into account and I try to emulate, to make people understand this ecological system, but perhaps without much success: I wrote and published this article (in French unfortunately but some have perhaps to be a translator)  https://www.aujardin.info/fiches/rhizosphere-micro-organismes-plantes-equipe-gagne.php  to make people understand that we must stop using pesticides and chemical fertilizers in the ground, at least in gardens.


 in pots, symbiosis and other mutual aid relationships cannot resist the use of chemical fertilizers, because mutual aid between plants and microorganisms must be give and take. However, if the plant has these directly assimilable nutrients, it has no reason to promote and nourish lactic acid bacteria and fungi. The latter if they exist, die or at best go dormant.

Likewise, insecticides have an effect on these microbiota, and fungicides kill some of the insects and other soil life. (let's not talk about us who also absorb it in the process)

 However, in a pot, a small volume, it is difficult to develop a plant without fertilizer, except by putting a little good compost or well decomposed manure, (which I do as soon as possible) but it does not necessarily suit to all.
Mycelia increase the exchange surface between the plant and its environment, but in pots, this is not really possible.

 Unless :
-use large pots
- to transplant in the ground as quickly as possible.

I have the example of an Iris (probably sibirica, unfortunately it comes from recycled pot soil, so I'm not sure). Germinated in a large pot (made for another plant) it grows 5 times faster than in a seedling pot. Germinated last spring and planted in the ground in the fall, it is currently making 12 new shoots, some of which will flower. He never had any fertilizer. But maybe your Iris sibirica usually grow this fast when grown well?