Thank you, IRISH 063.....
I chose to purchase the wettable powder product you mention above specifically because it contains only the endomycorrhizal fungus, Rhizophagus intraradices (a.k.a Glomus intraradices) and excludes other microbes (e.g. the aggressive tricodermas and non-arbuscular ectomychorrhizals.
I have learned from my readings online and in other forums that Cannabis benefits most from its unique symbiotic relationship with Rhizophagus intraradices (a.k.a. Glomus intraradices), and another endomycorrhizal species Glomus mosseae, that is also symbiotically associated with Cannabis. Of these two endomycorrhizae, Rhizophagus intraradices is the more plentiful and dominant species.
Today (Apr 08, 2018), I came across a published research study that may be helpful to those who are searching for a product containing mycorrhizae.
The article is entitled CROP-SPECIFIC AND SINGLE-SPECIES MYCORRHIZAL INOCULATION IS THE BEST APPROACH TO IMPROVE CROP GROWTH IN CONTROLLED ENVIRONMENTS, by authors Maarten Van Geel, Matthis De Beenhouwer, Bart Lieven and Oliver Honnay (June 2016). The lead author, Maarten Van Geel, is a well-published researcher with expertise in Soil Science, Environmental Science, Geostatistics, etc. Although this article does not deal specifically with Cannabis as a host plant, I think the author's conclusions support my decision to choose the single species product which contains Rhizophagus intraradices.
To ensure I have "all bases covered", I also purchased the 2.2 lb (1 kilogram) size bag of an endomycorrhizal mixture sold by another company. This other, granular, product contains a mixture of eight arbuscular myhorrhizal endomycorrhizal species (1) Glomus intraradices, a.k.a rhizophagus intraradices (104 propagules/gm), (2) Glomus deserticola (3) propagules/gm), (4) Glomus etunicatum (9 propagules/gm), (5) Glomus clarum (9 propagules/gm), (6) Glomus cloroidum (9 propagules/gm), (7) Glomus mosseae (9 propagules/gm) and (8)) Gigaspora albido (9 propagules/gm).
I have looked at many other popular products mentioned in these forums. All products purport to have beneficial fungi for cannabis with "Mycorrhizae". With so many products available, choosing where to spend one's money can be difficult.
What I look for in any containing live organisms, (1) I look for the expiration date which should be clearly visible and prominently stated on the package/bottle. Some products claim to be "good for 6 months from date of manufacture". Other products are supposedly "good for two years from date of manufacture", while other products do not have that vital information which forces the consumer to contact the manufacturer directly. The expiration date is extremely important to me because I want the freshest products which have been stored properly indoors and which were kept within a safe temperature range. I want to ensure I am buying a product that has the greatest number of live organisms. If I am going to spend money on a product with a shelf life, I expect the seller to give me the information I need to justify the expense. (2) Secondly, I look for the list of ingredients in the product in order to eliminate any product that contains Trichoderma and ectomycorrhizae (because I want endomycorrhizae). If I see the words "tricoderma" or "ectomycorrhizae" in the ingredients, I put the product back on the shelf and keep shopping.
I do not have enough knowledge to conclude that Trichoderma or ectomycorrhizae are unhelpful or may have adverse effects or cause any harm to Cannabis. So I kept searching for information.
In another article I came across, the suggestion was made that if you really, really, really want to add Trichoderma to soil for cannabis, one should first inoculate the plant's roots with endomycorrhizae to let those fungi get a head start in establishing themselves. According to that study, when Trichoderma was introduced into soil after the endomycorrhizal fungi had been given sufficient time (the article does not state how much time is sufficient) to grow and become well-established, the later introduction of Trichoderma did not apparently have as destructive or aggressive effects on the healthy, established resident colony of endomycorrhizal species.
Another thing I learned in this search for the appropraite mycorrhizal species for Cannabis: One grower tried to use Trichoderma as a foliar spray, with unfortunate results to the sprayed leaves. Lesson from this anecdote: If I see someone jump off a cliff to dive into a deep lagoon and observe that he does not pop back up to the surface of the water in a reasonable period of time....alive, unbloodied, and happily breathing....I will take that as a warning against repeating the act.
