TastyFrost
Member
Hi, does using organic liquid fertilisers kill mycorrhizae, or is it just chemical fertilisers that kill it? Also which ones are safe.
Thanks
Thanks
mycorrhizae with organics
- Thread starter TastyFrost
- Start date
download and read this.
http://www.saviskyproturf.com/28.html
a quick tip.... too much P has been known to inhibit the growth of mycorrhizae
http://www.saviskyproturf.com/28.html
a quick tip.... too much P has been known to inhibit the growth of mycorrhizae
not my thread but thank you, thank you, thank you!
and from your excellent link...
"Fertilization can produce large plants, but it often suppresses mycorrhiza
formation. Fertilization lacks or even suppresses the other
important benefits of mycorrhiza. Fertilization cannot increase plant
species diversity; it tends to favor large individuals of the few most
vigorous species. Fertilization cannot improve plant survival, but
rather tends to favor a few large plants rather than many smaller ones.
Fertilization does not make the site unfit for weeds, but instead gives
them a nearly insurmountable competitive edge against native plants.
Fertilization does nothing to decrease root disease, favor beneficial
bacteria, or improve soil structure, perhaps the most important effects
of mycorrhiza in natural systems. In a revegetation project, fertilization
is often a serious mistake."
and from your excellent link...
"Fertilization can produce large plants, but it often suppresses mycorrhiza
formation. Fertilization lacks or even suppresses the other
important benefits of mycorrhiza. Fertilization cannot increase plant
species diversity; it tends to favor large individuals of the few most
vigorous species. Fertilization cannot improve plant survival, but
rather tends to favor a few large plants rather than many smaller ones.
Fertilization does not make the site unfit for weeds, but instead gives
them a nearly insurmountable competitive edge against native plants.
Fertilization does nothing to decrease root disease, favor beneficial
bacteria, or improve soil structure, perhaps the most important effects
of mycorrhiza in natural systems. In a revegetation project, fertilization
is often a serious mistake."
I have read though that once the mycorrhizae are established, the phosphorus only stops them from growing further, but only huge amounts outright kill them off. Makes me suspect that when adding phosphorus to the soil, one should do so in smaller amounts over time rather than all at once.
HortProOrganics
Member
Gargantuan, immense colonies with kelp meals, along with Bacillus and Trichoderma, in my experience. I always go the way of teas and dry meals, along with my straight earthworm casting syrup. Never had a balancing problem with P in my containers. Now, conventional applications with synthetic or only 90% organic supplements/ferts, totally different story.
LadyLargely
Member
Aha!
Excellent discussion here, lots of good thoughts.
My good man jaykush. That handy hunk of reference material you have provided here could well as be a part of the my Bible! The good Dr. St. John definitely knows what he's on about, and his reference tags and back-list beggar belief. He has pulled a gargantuan amount of hard data, but the article is still not crazy-difficult to digest. I've been up till past 6 in the goddamn morning reading it, and having covered a good strong 90% of the material presented. I've put it up as the first official outside reference manual for Club Bio Box. Its awesome.
Becoming intimately familiar with the awesome science in that reference would definitely be a huge help to anyone looking to go organic. This kind of stuff, beneficial microbes that can live in soil, are the single largest benefit of going organic.
But I figure some practical experience could help out the OP as well!
TastyFrost:
Everyone has provided good answers and it is starting to paint the real picture: There are a lot of variables involved in your question.
To answer what you asked quickly: liquid organic ferts should be fine for beneficial microbes. I would recommend bubbling such ferts up as a tea in the final dilute before applying it to the soil for extra microbe power! In general, any kind of strong mineral based nutrient will kill off Mycorrhiza. The biggest culprits are salt-based nutrients, more neutral stuff like non-organic CAL-MAG substances tend to be fine. But this can all be elaborated on:
What you overall are asking about is fungal vigor. Given different environments and nutrients to consume various breeds of Mycorrhiza fungus will operate at various levels of strength.
In a normal pot of well-amended organic soil a nice variety of dormant Mycorrhiza spores will take over rapidly and perform quite well. The trouble is keeping that happy environment the same over a long period of time. Soil compaction and lost space due to the damn thing filling with roots not to mention the build-up of non-nutritious water-insoluble material that is inherent to organic fertilizers.
Even still, fungus developed this way does very well and will be quite stable. But as several have mentioned, that stability is a bit of a balancing act. A nearly 100% organic nute regime complete with high-carbohydrate amendments (lots of kelp) is basically a must to achieve a strong mycelium network in the medium. Usage of strong salt nutes of any kind has been long-considered an invitation for failure.
And so it has been for some time.
Recently, a small clutch of gardeners have looked to get around the limitations of traditional soil-based grows. Creating a more specific soil-based environment to end up with more flexible microbes.
The result has been the aforementioned Bio Box. The idea is to inject oxygen into a super-low-density soil-based medium. Various design elements are needed to keep it contained and wet and not turn into a soup, but its all pretty straightforward. The result is a brand of beneficial microbes which are unusually resilient.
And active! Do what you want to the soil, the pH will get automatically balanced by the microbes. They are so flexible and have such a large margin of control over the soil chemistry that a well-established Bio Box will withstand doses of salt-based fertilizers with Mycorrhiza colonies happily in-tact.
Keep the salt nutrient sources high-quality and the dosages reasonable and properly maintained Mycorhizae colonies can live through plenty of artificial fertilization. Its best to save this ability for times of heavy blooming, between starve/flush cycles where the nugs really start to wad up!
Can't say I really endorse this ability, I think it spoils the founding ideas of oxygen injected organics a little bit. I prefer to run my Mycorrhizae colonies on 100% organic nutrient sources. But Bio Box is all about Flexibility, so the capability should be put out there.
The power and survival abilities of Mycorrhiza just gets more and more astonishing the more you know about it. I think Bio Box is a great way to leverage it, but really all organic gardeners need to embrace the wonder-fungus somehow. What method you choose to use and the environment in which you cultivate Mycorrhizae will have a strong impact on how powerful your colonies will be. And that means how much abuse they can take
Excellent discussion here, lots of good thoughts.
My good man jaykush. That handy hunk of reference material you have provided here could well as be a part of the my Bible! The good Dr. St. John definitely knows what he's on about, and his reference tags and back-list beggar belief. He has pulled a gargantuan amount of hard data, but the article is still not crazy-difficult to digest. I've been up till past 6 in the goddamn morning reading it, and having covered a good strong 90% of the material presented. I've put it up as the first official outside reference manual for Club Bio Box. Its awesome.
Becoming intimately familiar with the awesome science in that reference would definitely be a huge help to anyone looking to go organic. This kind of stuff, beneficial microbes that can live in soil, are the single largest benefit of going organic.
But I figure some practical experience could help out the OP as well!
TastyFrost:
Everyone has provided good answers and it is starting to paint the real picture: There are a lot of variables involved in your question.
To answer what you asked quickly: liquid organic ferts should be fine for beneficial microbes. I would recommend bubbling such ferts up as a tea in the final dilute before applying it to the soil for extra microbe power! In general, any kind of strong mineral based nutrient will kill off Mycorrhiza. The biggest culprits are salt-based nutrients, more neutral stuff like non-organic CAL-MAG substances tend to be fine. But this can all be elaborated on:
What you overall are asking about is fungal vigor. Given different environments and nutrients to consume various breeds of Mycorrhiza fungus will operate at various levels of strength.
In a normal pot of well-amended organic soil a nice variety of dormant Mycorrhiza spores will take over rapidly and perform quite well. The trouble is keeping that happy environment the same over a long period of time. Soil compaction and lost space due to the damn thing filling with roots not to mention the build-up of non-nutritious water-insoluble material that is inherent to organic fertilizers.
Even still, fungus developed this way does very well and will be quite stable. But as several have mentioned, that stability is a bit of a balancing act. A nearly 100% organic nute regime complete with high-carbohydrate amendments (lots of kelp) is basically a must to achieve a strong mycelium network in the medium. Usage of strong salt nutes of any kind has been long-considered an invitation for failure.
And so it has been for some time.
Recently, a small clutch of gardeners have looked to get around the limitations of traditional soil-based grows. Creating a more specific soil-based environment to end up with more flexible microbes.
The result has been the aforementioned Bio Box. The idea is to inject oxygen into a super-low-density soil-based medium. Various design elements are needed to keep it contained and wet and not turn into a soup, but its all pretty straightforward. The result is a brand of beneficial microbes which are unusually resilient.
And active! Do what you want to the soil, the pH will get automatically balanced by the microbes. They are so flexible and have such a large margin of control over the soil chemistry that a well-established Bio Box will withstand doses of salt-based fertilizers with Mycorrhiza colonies happily in-tact.
Keep the salt nutrient sources high-quality and the dosages reasonable and properly maintained Mycorhizae colonies can live through plenty of artificial fertilization. Its best to save this ability for times of heavy blooming, between starve/flush cycles where the nugs really start to wad up!
Can't say I really endorse this ability, I think it spoils the founding ideas of oxygen injected organics a little bit. I prefer to run my Mycorrhizae colonies on 100% organic nutrient sources. But Bio Box is all about Flexibility, so the capability should be put out there.
The power and survival abilities of Mycorrhiza just gets more and more astonishing the more you know about it. I think Bio Box is a great way to leverage it, but really all organic gardeners need to embrace the wonder-fungus somehow. What method you choose to use and the environment in which you cultivate Mycorrhizae will have a strong impact on how powerful your colonies will be. And that means how much abuse they can take
I think he just means more flexible in terms of what sorts of food they can consume without being damaged. Obviously microbes developed in a loose medium would not develop to move through dense material as well. Life tends to fit itself to it's environment. It probably isn't flexible in all ways, but being able to safely process chemical nutrients could make that solution a good transitional solution for farmers not willing or able to give up chemical sources right away.
LadyLargely
Member
Magiccannabus has hit the nail on the head here. Oxygen-injected microlife is not more flexible overall, it does not become a super-species. It cannot do anything its genetics didn't dictate in the first place.
What happens with oxygen injection, what sets Bio Box apart, is increased matabolism of the present microbes.
This makes them better at consuming new raw matirials, they are able to work faster and make more rapid adjustments to the soil chemistry. This doesn't mean they are more effective. Nothing about the microbes have changed. Its just the fact that they have a greater avalibility of raw matirials to work with.
All life is based on some kind of metabolism, some form of raw material consumption to drive energy production. Mitochondria are the specialized inner-cell organs that allow this to occur. One of the most impressive things about this process is its scalability. Two genetically identical organisms can have vastly different food consumption, and therefore energy production rates. A starving cow may live for weeks with no food because its metabolism slows down. Conversely, treated the right way a dairy cow's metabolism can be ramped up enough that it can consume grain and produce more than a hundred pounds of milk a day! Same cow, vastly different levels of performance based on different conditions.
Likewise, Bio Box gardeners are able to ramp up the metabolisms of the microbes present in our medium.
You have to remember that Bio Box creates a very specific environment. The ability of Mycorrhizal fungus to do so much better in Bio Boxes is due to this specificness. Bio Boxes are actually much less biodiverse than ordinary organic soil. In normal soil you still get plenty of anaerobic life that contributes quite a bit to the overall biomass of that environment. In Bio Boxes anaerobic life cannot possibly survive. This is why I say Bio Box is not 'better', just more specific. In certain ways this makes Bio Box much less flexible than its ordinary soil counterparts. However the lost flexibility covers things like the capability of a soil to rapidly decompose freshly dead matter. A good patch of forest soil could decompose a dead body quite quickly. Bio Box soil could never do this. Bio Box has been designed to sacrifice flexibility that home gardeners do not need in order to enhance flexibility that we could use more of.
As far as unsupported by evidence you just have to know where to look and what to look for. True, the idea that Bio Box style oxygen injection automatically leads to stronger micro-life is not currently proven by hard science.
But, it is well scientifically-proven, as a rule, that More Oxygen = More Mycorrhiza
Bio Box gardeners are assuming that these hard scientific principals scale up to cover oxygen injection. There is not yet enough hard scientific evidence to prove this directly, but the real-world results that Bio Box gardeners have seen are compelling:
Our ability to add nutrients to the medium without fear of pH fluctuation raises interesting questions if you don't believe me directly. Just what could cause that to happen? The current assumption is that it is happening because of soil chemistry modifications made by microbes with ramped-up metabolisms. There is not currently enough evidence to prove this as true, but given that the next competing theory is that pH Pixies are taking care of our soil chemistry we are compelled to believe it is due to Increased Microherd Metabolism.
FWIW: Why I don't suggest using AM fungi when growing Cannabis spp.:
I came to the conclusion, backed up by data, that soils with even moderate levels of *organic* P (~>0.5% P), can and will hinder AM fungi (especially important is the N/P ratio). Available organic minerals are of most concern and at the stated level can hinder or prevent AM fungi growth and reproduction. See the paper by David D. Douds, PhD, titled "On-farm Production and Utilization of AM Fungus Inoculum"[1].
I have also been researching time frame (days, weeks, months) for fractional and full infection % and values of various hosts roots by various AM species (mostly Glomus spp.). It seems full infection (~70-90%) occurs around and between the 5th to 10th weeks after inoculation of soil (or media) with live AM fungi inoculum propagules[2][3][4], not freeze dried spores which is what nearly every 'weed' grower uses :sad: ...
I have been researching those two topics (P quantity and infection time) in regards to use of AM fungi with Cannabis spp. cultivation. Almost every 'grower' uses AM not at their own fault, but at the falut of the industry hype. Even those who use chemical fertilizers tend to apply AM fungi! It turns out that over 32ppm of P (chemical) will almost totally inhibit AM fungi infections (value = 0)[1].
After much research I have come to the conclusion that the use of AM fungi when growing Cannabis spp. is not wise as it's merely a waste of money. The problem is two fold: (1) infection time frame considering the average cultivation time of Cannabis spp. (~2-3 months indoor; ~2-5 months outdoor) and (2) the usage of high levels of P (organic or chemical) which is necessary for intense Cannabis spp. cultivation. The former issue (1) is a problem if one uses freeze dried AM fungi spores as inoculum, not when using live AM fungi inoculum. The use of freeze dried AM fungi spores greatly slows the infection time frame, probably past the point of usefulness for Cannabis culture. The latter issue (2) is a problem because low levels of P, even with fully AM infected host roots, is most probably going to lower the Cannabis flower quality and yield.
Also of note is most AM fungi products (ie. freeze dried spores) are mixed with freeze dried Trichoderma spp. spores! This is not wise because the Trichoderma spp. will grow and reproduce much more quickly than the AM fungi spores, thus the Trichoderma spp. will parasite the AM fungi spores and hyphae. The AM fungi must first be in a mycorrhiza association and be thiving, then Trichorderma spp. could be introduced. However, in my opinion, it is redundant to use Trichoderma spp. AND AM fungi because the AM fungi can protect the “extraradical environment” (eg. soil around rhziosphere), the rhizosphere and host roots as well as, or better than Trichoderma spp.; besides, AM fungi offers so many other great benefits. There are some studies which found Trichoderma spp. to have a synergistic relationship with some AM fungi[5] and should be “...designated as mycorrhizal helper organism..."[6].
[1] “On-farm Production and Utilization of AM Fungus Inoculum”
Author(s): David D. Douds, PhD.
USDA-ARS Eastern Regional Research Center, June 16, 2009
[2] “Infection of Vesicular-Arbuscular Mycorrhizal Fungi to Plants and Spore Numbers in Cultivated Soils in Miyagi Prefecture”
Authoer(s): Kanehito Sansai
August, 31, 1992
[3] “Modeling arbuscular mycorrhizal infection: is % infection an appropriate variable?”
Author(s): Michael F. Allen
Mycorrhiza (2001) 10:255–258
[4] “Quantification of Active Vesicular-Arbuscular Mycorrhizal Infection Using Image Analysis and Other Techniques”
Author(s): S.E. Smith and S. Dickson
Department of Soil Science, Waite Agricultural Research Institute,
Glen Osmond, SA 5064, Australia.
Aust. J. Plant Physiol., 1991, IS, 637-48
[5] "Interactions between the arbuscular mycorrhizal fungus Glomus mosseae and plant growth-promoting fungi and their significance for enhancing plant growth and suppressing damping-off of cucumber"
by W.A. Chandaniea, M. Kubotab and M. Hyakumachi
[6] "Enhanced growth and nutrition of micropropagated Ficus benjamina to Glomus mosseae co-inoculated with Trichoderma harzianum and Bacillus coagulans"
by Jayanthi Srinath, D.J. Bagyaraj, and B.N. Satyanarayana
I reserve the right to edit this for typo's I tend to make, haha. I will post this and then read it, again, to look for anything stupid I wrote :smile:
Hi,
I don't have much time to post or read but I do try to scan them from time to time. And this time this thread caught my eye.
This is a great question and isn't considered nearly enough. I'll answer the O.P.s question, but I also want to correct some statements from the PDF JayKush linked to. Thanks to Jay Kush for that link, overall it is a very well written paper, however, I found many errors and inaccuracies. Because the paper is quite good overall, and many people will benefit from reading it, I want to try and correct the errors I believe I found so people will not learn inaccuracies about mycorrhizal fungi and mycorrhizal plants/trees/grasses.
I'm just gonna copy/paste statements from the paper here. I will write what I think are corrections for the inaccuracies/errors I believe I found in the paper (no disrespect to the author). I am considering emailing the author, Ted St. John, Ph. D. sometime this week about my concerns and corrections.
OP's Question:
Yes and yes. It depnedings upon usage (see below)...
Surprising low levels of organic and inorganic P can cause AM fungi inhibition. In my opinion, the inhibitory level of P is much too low for intense growth of Cannabis spp. (see the following quotes). The level of organic phosphorus (esp. available P) which hinders AM fungi is very low at NPK ~>0.5% P (esp. considering N/P ratio where it seems ~=>5/1 is suggested). And =>32ppm P (inorganic chemical) prevents growth and reproduction of AM fungi, that is too low for intense growth of Cannabis spp. At 32 ppm P the AM fungi infection rate and “extraradical” mycelium growth has a value of 0.[1]
QUOTES:
“General considerations
An important consideration in AM fungus production is the level of available P in the media in which the plant hosts are grown. Plants growing in high P situations limit colonization of their roots by AM fungi. In effect, they are deciding to limit the “cost” (in terms of sugar) of the symbiosis in the absence of benefit (in this case, improved uptake of phosphorus) since the roots can function well enough on their own in the high nutrient situation. The reduction of colonization then limits the fungus’ ability to acquire sugars for growth and reproduction. This phenomenon is also important in the greenhouse production phase for the growth of inoculated vegetable seedlings, as we will see later.”[1]
…
“Maximal production of inoculum in this system requires the proper dilution of the nutrient rich compost with a nutrient poor substrate such as vermiculite. This is because colonization of roots by AM fungi, and hence growth of the fungus, is inhibited by high nutrient levels, notably of available P (see the general considerations, above). We did try growing the bahiagrass plants in pure compost one year and saw no spread of colonization within the root system or spore production by AM fungi. Further, the extent of the dilution will vary for composts with different nutrient levels. Table 1 shows important characteristics of three composts studied in the development of this technology. We conducted a complete factorial experiment (all possible combinations were examined) with three AM fungi, three composts, and five dilution ratios. Inoculum production was quantified in terms of spore production by the fungi (Fig. 1). Notice how spore production in the composts with the lower P levels and high N
ratios (yard clippings compost and dairy manure plus leaf compost) was better at lower dilutions while that in the compost with high P and low N ratio (controlled microbial compost) was better when the compost was diluted more. We have developed predictive equations (Douds et al., 2008) in which compost nutrient levels are used to estimate compost and vermiculite dilutions for the growth of three AM fungi. In general, however, we have had success routinely with dilutions ratios of 1:3 to 1:9 (1:4 typically) compost:vermiculite, volume basis.”[1]
…
“Organic growers must find a different strategy to adjust P availability in their potting media. We have conducted experiments on this topic, but as yet only preliminary information is available (Table 2). We utilized an organically approved potting mix (NP mix from Living Acres, New Sharon, ME) with an NPK analysis of 0.4–0.5–0.3. The manufacturer recommends no nutrient addition to young plants grown in this media in the greenhouse. However, since P appeared to be high relative to N, we added two further treatments to the experiment. In addition to growing plants in media amended only with the inoculum, we grew plants in the media mixed 1:1 with vermiculite with and without a supplemental low P fertilizer (“Biogrow,” 1.8–0.1–6.6 from Biobizz, Groningen, The Netherlands). Ten mL of a stock solution containing 11.67 ml of the concentrated Biogrow per L was applied three times each week for 5 weeks. This supplied the same amount of supplemental N as was given in the inorganic treatments in the previous work (Figure 4). The goal of this work is to develop a regime in which plants are sufficiently colonized by AM fungi and of a size that is competitive with plants grown in high P. The results were mixed, and appeared to vary by cultivar (Table 2). Diluting the potting medial with vermiculite tended to decrease shoot growth, and this was alleviated by the extra nutrient addition. The effect upon colonization by AM fungi was inconsistent, but told us we are headed in the right direction. However, colonization of plants grown in the unamended media was still better than we have found in conventionally managed greenhouses, so we recommend this to growers as a place to start.”[1]
…
“To have beneficial associations between the fungus and plant roots, a low but sufficient level of P in the soil or rooting medium is needed. If the soil P level is extremely low, the fungus can be parasitic (harmful to the plant) rather than beneficial, because it will compete with the plant for available P. When soil P is high (above “sufficient”), the plant can obtain enough P without the fungus, and the association will not be formed.d”[2]
…
and to all those who use chem ferts and AM fungi!:
“On-farm Production and Utilization of AM Fungus Inoculum – eXtension that colonization decreased with increasing P level to effectively zero at 32 ppm PAfter the seedlings have been transplanted into the inoculated potting media, the next decision is proper choice of fertilization regime, especially for conventional growers. With too much phosphorus, plants will not become colonized and the inoculum—or the money used to purchase the inocula—will have been wasted. To aid the conventional grower
in this decision, we conducted an experiment to describe the response of AM fungus colonization of tomato and pepper roots to added P. Plants received, three times per week, 10 mL of a balanced, complete nutrient solution (Hoagland and Arnon, 1938) adjusted to supply P levels ranging from 0.31 to 62 ppm P as KH2PO4. Nitrogen was supplied as KNO3 and Ca(NO3)2 and was 210 ppm for all treatments. Results underscored the need to control P applications and showed that colonization decreased with increasing P level to effectively zero at 32 ppm P (Fig. 4).”[1]
Discussing Statements in “The Instant Expert Guide to Mycorrhiza” by Ted St. John, Ph. D.
(page 1, paragraph 1)
There are a few different 'types' of mycorrhizal associations which can vary between (inter-) Family, Genus, species and even intraspecies (aka “intraspecific”)[3]:
However, there is only one known 'type' of AM fungi, and that would be “obligate symbiont”[1]. AM fungi can not grow or reproduce without its' associated host plant root biomass for food (as special types of carbohydrates). The only exception I can think of is where a clone AM fungus has no mycorrhiza association and could 'fuse' (via. "anastomoses") with another clone AM fungus which has a mycorrhiza association, thus the first AM fungus clone could 'feed' off of the second AM fungus clone and the host plant it has a mycorrhiza association with. The caveat here is I'm not sure if that would happen. I have not researched AM fungi anastomoses too far, but I have yet to read of an instance I just described. In all cases I have read each AM fungus clone has its' own host plant with mycorrhiza association.
Not to mention plants which are mycorrhizal do not need to be infected to grow, and grow well. The plant just need the media bound microbes to breakdown organic amendments (nutrients like P) into forms available to the roots (via. Soil foodweb). Besides, even when a root system is 'fully' infected, which means infection of ~70-90% of total host root biomass within about the first 10 cm of media, the bio-chemical processes of the micro-herd will still provide P which the roots will adsorb, along with the P pipped directly into the roots by the AM fungi. If there is 'too much' available P in the media (organic or inorganic) the plant will use that P, and in turn AM fungi, and mycorrhiza associations are hindered.
(page 1, paragraph 2)
“[...]They make plant growth possible,[...]”. True in most cases, in nature. However, mycorrhizal plants/trees/grasses strictly make AM fungi growth possible. The fact is non-obligate mycorrhizal plants can grow without their associated AM fungi, however, the associated AM fungi can not grow or live without the host.
“[...]control the mix of plant species on the site,[...]”. Yes, however, this is in soils with high AM fungi biomass (spores, hyphae and mycelium (free and in mycorrhiza association to existing host roots)). In soils with low AM fungi biomass it's generally the plants/trees/grasses roots exudes which control much of the microbial biomass (micro-herd) within and immediately surrounding the rhizosphere. Colonizing soils which have low AM fungi biomass with AM fungi inocula to increase the AM fungi biomass is no easy task...and I know of NO professional horticulturist or botanist who would prefer to use freeze dried spores as AM fungi inoculum (which is the de facto standard for growing 'weed'). The standard is a *living* mix of hyphae, spores and infected host root biomass.
“[...]and dominate the microflora, selecting a soil full of “good bugs” when the site might otherwise fill up with pathogens.[...]”. That would be an accurate statement for soils rich in AM fungi biomass, like old-growth forests or prairie grasslands, not like soil tilled on a yearly basis, or soils with high clay or sand fractions. The plants/trees/grasses are in control of the micro-herd within the rhizosphere and immediate surroundings in many situations.
(page 1, paragraph 3)
(page 1, paragraph 4)
(page 2, paragraph 1)
AM fungi do in fact fix, and even *transport* (via. extraradical mycelium) nitrogen to host plants, along with absorbing and transporting P, S, Ca, K, Fe, Cu, Zn to host plant roots[5][6][7]. AM fungi not only aids in P and N uptake by the host, along with other minerals, but acts as a defensive barrier (via metabolites, enzymes, etc) against harmful microbes, protecting the host rhizosphere, along with providing an extended water resource (ie. pseudo roots), etc.
(page 3, paragraph 2)
(page 4, paragraph 1)
a) “Manual on Arbuscular Mycorrhizal Fungus Production and Inoculation Techniques”
Author(s): S.C. Miyasaka, M. Habte, J.B. Friday, and E.V. Johnson1
Departments of Tropical Plant and Soil Sciences and Natural Resources and Environmental Management
Soil and Crop Management, July 2003, SCM-5
b) “On-farm Production and Utilization of AM Fungus Inoculum”
Author(s): David D. Douds, PhD.
USDA-ARS Eastern Regional Research Center, June 16, 2009
c) “Appendix I. Checklist of steps for the on-farm production of arbuscular mycorrhizal [AM] fungus inoculum”
This appendix accompanies the article, “On-farm Production and Utilization of
AM Fungus Inoculum”, by David D. Douds Jr., USDA-ARS Eastern Regional Research Center.
d) “Arbuscular Mycorrhizas: Producing and Applying Arbuscular Mycorrhizal Inoculum”
Author(s): M. Habte and N.W. Osorio.
This book may be purchased from CTAHR; obtain an order form at:
http://www.ctahr.hawaii.edu/oc/forsale/AMFflier.pdf
(page 4, paragraph 6)
(page 6, paragraph 1)
Use of a “brightfield” compound microscope (among others) enables one to rather easily identity whether or not the spore (or mycelium/hyphae) is in fact, AM fungi. Anyone reading this could do so with a ~$700.00 dollar microscope (comprable/better than the Lecia CME, ~>$1,500) and a few taxonony references.
Visable with the Naked Eye: AM fungi extraradical mycelium network extension outward:
(page 10, paragraph 2)
(page 27, paragraph 2-5)
(note: live “propagules” (spores, hyphae/mycelium, infected host roots) are used for inoculum)
“Mixing inoculum into the potting media:
The next real decision-making step occurs when it is time to mix the inoculum into the potting media. There are two things to consider here: the potency of your inoculum, and the rooting volume of the cells in which the plants will be grown. Three years of on-farm production of AM fungi at 7 cooperating farms as part of a SARE grant yielded an average of 82 ± 20 propagules of AM fungi cm-3 (SARE grant LNE 03-179 final report). Propagule numbers averaged 503, 240, and 42 propagules cm-3 for the 1:4, 1:9, and 1:99 mixtures of yard clippings compost and vermiculite (Douds et al., 2006). Though this indicates only several cm3 of inoculum would be needed per planting cell to reach a target of 100-200 propagules of AM fungi per plant, it is very difficult to uniformly mix the inoculum into the potting media at a rate of only 1-2% by volume. We recommend utilizing the inoculum at a dilution of 1:9 or 1:19 (inoculumotting media, volume basis). This comes as a result of an experiment conducted with 8 cultivars each of tomato and pepper. Plants were grown in a greenhouse for 4 weeks in 50-cell flats (70 cm3 per cell). Two sets of plants were grown in horticultural potting media: one amended with inoculum at a 1:9 and the other at a 1:19 (inoculumotting media, volume basis) dilution ratio. The initial, pure inoculum had a propagule density of 120 propagules cm-3. At the end of the experiment, tomato plants averaged 30.5% and 12.9% root length colonized by AM fungi for the 1:9 and 1:19 dilutions, respectively. Pepper averaged 14.8% and 8.0% root length colonized. All of these colonization intensities are sufficient to potentially produce a growth response. Choice between the 1:9 or 1:19 amendment would depend upon individual flat cell size. Cells that are 50 cm3 or smaller should be filled with media amended 1:9 with inoculum to ensure proper mixing and sufficient number of propagules.”[1]
[1] “On-farm Production and Utilization of AM Fungus Inoculum”
Author(s): David D. Douds, PhD.
USDA-ARS Eastern Regional Research Center, June 16, 2009
[2] “Manual on Arbuscular Mycorrhizal Fungus Production and Inoculation Techniques”
Author(s): S.C. Miyasaka, M. Habte, J.B. Friday, and E.V. Johnson1
Departments of Tropical Plant and Soil Sciences and Natural Resources and Environmental Management
Soil and Crop Management, July 2003, SCM-5
[3] “Adaptive significance of endomycorrhizas for herbaceous plants”
Journal of Russian Ecology
Volume 37, Number 1, January, 2006
[4] “Interspecific variation in plant responses to mycorrhizal colonization in tallgrass prairie”
Author(s): Gail W.T. Wilson and David C. Hartnett
Division of Biology, Kansas State University
[5] “External Hyphae of Vesicular-Arbuscular Mycorrhizal Fungi Associated with Trifolium subterraneum L. 3. Hyphal Transport of 32P and 15N”
Author(s): A. Johansen, I. Jakob Sen and E.S. Jensen
Plant Biology Section, Environmental Science and Technology Department,
Riso National Laboratory, DK-4000 Roskilde, Denmark
(Received 26 June 1992, accepted 13 January 1993)
[6] “The Biology of Mycorrhiza in the Ericaceae. IV. The Effect of Mycorrhizal Infection on Uptake of 15N from Labelled Soil by Vaccinium macrocarpon Ait.”
Author(s): D. P. Stribley and D. J. Read
Source: New Phytologist, Vol. 73, No. 6 (Nov., 1974), pp. 1149-1155
[7] “At the Root of the Wood Wide WebSelf Recognition and Non-Self Incompatibility in Mycorrhizal Networks”
Author(s): Manuela Giovannetti, Luciano Avio, Paola Fortuna, Elisa Pellegrino, Cristiana Sbrana, and Patrizia Strani
Department of Crop Plant Biology; CNR; UO Pisa; Pisa, Italy
Institute of Biology and Agriculture Biotechnology; CNR; UO Pisa; Pisa, Italy
Copyright © 2006 Landes Bioscience
[8] “The occurrence of anastomosis formation and nuclear exchange in intact arbuscular mycorrhizal networks”
Autor(s): Manuela Giovannetti, Paola Fortuna, Anna Silvia Citernesi, Stefano Morini and Marco Paolo Nuti
Dipartimento di Chimica e Biotecnologie Agrarie, Centro di Studio per la Microbiologia del Suolo, C. N. R., Università di Pisa, Via del Borghetto 80, 56124
Pisa, Italy; 29, March, 2001
[9] “Infection of Vesicular-Arbuscular Mycorrhizal Fungi to Plants and Spore Numbers in Cultivated Soils in Miyagi Prefecture”
Authoer(s): Kanehito Sansai
August, 31, 1992
[10] “Modeling arbuscular mycorrhizal infection: is % infection an appropriate variable?”
Author(s): Michael F. Allen
Mycorrhiza (2001) 10:255–258
[11] “Quantification of Active Vesicular-Arbuscular Mycorrhizal Infection Using Image Analysis and Other Techniques”
Author(s): S.E. Smith and S. Dickson
Department of Soil Science, Waite Agricultural Research Institute,
Glen Osmond, SA 5064, Australia.
Aust. J. Plant Physiol., 1991, IS, 637-48
[12] “Structure, Extent and Functional Significance of Belowground Arbuscular Mycorrhizal Networks Author(s): M.Giovannetti
Department of Crop Plant Biology, University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
Hi,
I don't have much time to post or read but I do try to scan them from time to time. And this time this thread caught my eye.
This is a great question and isn't considered nearly enough. I'll answer the O.P.s question, but I also want to correct some statements from the PDF JayKush linked to. Thanks to Jay Kush for that link, overall it is a very well written paper, however, I found many errors and inaccuracies. Because the paper is quite good overall, and many people will benefit from reading it, I want to try and correct the errors I believe I found so people will not learn inaccuracies about mycorrhizal fungi and mycorrhizal plants/trees/grasses.
I'm just gonna copy/paste statements from the paper here. I will write what I think are corrections for the inaccuracies/errors I believe I found in the paper (no disrespect to the author). I am considering emailing the author, Ted St. John, Ph. D. sometime this week about my concerns and corrections.
OP's Question:
Yes and yes. It depnedings upon usage (see below)...
Surprising low levels of organic and inorganic P can cause AM fungi inhibition. In my opinion, the inhibitory level of P is much too low for intense growth of Cannabis spp. (see the following quotes). The level of organic phosphorus (esp. available P) which hinders AM fungi is very low at NPK ~>0.5% P (esp. considering N/P ratio where it seems ~=>5/1 is suggested). And =>32ppm P (inorganic chemical) prevents growth and reproduction of AM fungi, that is too low for intense growth of Cannabis spp. At 32 ppm P the AM fungi infection rate and “extraradical” mycelium growth has a value of 0.[1]
QUOTES:
“General considerations
An important consideration in AM fungus production is the level of available P in the media in which the plant hosts are grown. Plants growing in high P situations limit colonization of their roots by AM fungi. In effect, they are deciding to limit the “cost” (in terms of sugar) of the symbiosis in the absence of benefit (in this case, improved uptake of phosphorus) since the roots can function well enough on their own in the high nutrient situation. The reduction of colonization then limits the fungus’ ability to acquire sugars for growth and reproduction. This phenomenon is also important in the greenhouse production phase for the growth of inoculated vegetable seedlings, as we will see later.”[1]
…
“Maximal production of inoculum in this system requires the proper dilution of the nutrient rich compost with a nutrient poor substrate such as vermiculite. This is because colonization of roots by AM fungi, and hence growth of the fungus, is inhibited by high nutrient levels, notably of available P (see the general considerations, above). We did try growing the bahiagrass plants in pure compost one year and saw no spread of colonization within the root system or spore production by AM fungi. Further, the extent of the dilution will vary for composts with different nutrient levels. Table 1 shows important characteristics of three composts studied in the development of this technology. We conducted a complete factorial experiment (all possible combinations were examined) with three AM fungi, three composts, and five dilution ratios. Inoculum production was quantified in terms of spore production by the fungi (Fig. 1). Notice how spore production in the composts with the lower P levels and high N
ratios (yard clippings compost and dairy manure plus leaf compost) was better at lower dilutions while that in the compost with high P and low N ratio (controlled microbial compost) was better when the compost was diluted more. We have developed predictive equations (Douds et al., 2008) in which compost nutrient levels are used to estimate compost and vermiculite dilutions for the growth of three AM fungi. In general, however, we have had success routinely with dilutions ratios of 1:3 to 1:9 (1:4 typically) compost:vermiculite, volume basis.”[1]…
“Organic growers must find a different strategy to adjust P availability in their potting media. We have conducted experiments on this topic, but as yet only preliminary information is available (Table 2). We utilized an organically approved potting mix (NP mix from Living Acres, New Sharon, ME) with an NPK analysis of 0.4–0.5–0.3. The manufacturer recommends no nutrient addition to young plants grown in this media in the greenhouse. However, since P appeared to be high relative to N, we added two further treatments to the experiment. In addition to growing plants in media amended only with the inoculum, we grew plants in the media mixed 1:1 with vermiculite with and without a supplemental low P fertilizer (“Biogrow,” 1.8–0.1–6.6 from Biobizz, Groningen, The Netherlands). Ten mL of a stock solution containing 11.67 ml of the concentrated Biogrow per L was applied three times each week for 5 weeks. This supplied the same amount of supplemental N as was given in the inorganic treatments in the previous work (Figure 4). The goal of this work is to develop a regime in which plants are sufficiently colonized by AM fungi and of a size that is competitive with plants grown in high P. The results were mixed, and appeared to vary by cultivar (Table 2). Diluting the potting medial with vermiculite tended to decrease shoot growth, and this was alleviated by the extra nutrient addition. The effect upon colonization by AM fungi was inconsistent, but told us we are headed in the right direction. However, colonization of plants grown in the unamended media was still better than we have found in conventionally managed greenhouses, so we recommend this to growers as a place to start.”[1]
…
“To have beneficial associations between the fungus and plant roots, a low but sufficient level of P in the soil or rooting medium is needed. If the soil P level is extremely low, the fungus can be parasitic (harmful to the plant) rather than beneficial, because it will compete with the plant for available P. When soil P is high (above “sufficient”), the plant can obtain enough P without the fungus, and the association will not be formed.d”[2]
…
and to all those who use chem ferts and AM fungi!:
“On-farm Production and Utilization of AM Fungus Inoculum – eXtension that colonization decreased with increasing P level to effectively zero at 32 ppm PAfter the seedlings have been transplanted into the inoculated potting media, the next decision is proper choice of fertilization regime, especially for conventional growers. With too much phosphorus, plants will not become colonized and the inoculum—or the money used to purchase the inocula—will have been wasted. To aid the conventional grower
in this decision, we conducted an experiment to describe the response of AM fungus colonization of tomato and pepper roots to added P. Plants received, three times per week, 10 mL of a balanced, complete nutrient solution (Hoagland and Arnon, 1938) adjusted to supply P levels ranging from 0.31 to 62 ppm P as KH2PO4. Nitrogen was supplied as KNO3 and Ca(NO3)2 and was 210 ppm for all treatments. Results underscored the need to control P applications and showed that colonization decreased with increasing P level to effectively zero at 32 ppm P (Fig. 4).”[1]
Discussing Statements in “The Instant Expert Guide to Mycorrhiza” by Ted St. John, Ph. D.
(page 1, paragraph 1)
It seems the author wants the reader to think all plants/trees/grasses need AM fungi or they “[...]could not survive[...]”, which is pretty ambiguous and boarders on inaccurate. If we key in on the last few words “[...]in nature[...]” then the sentence is true. Reason being most natural soils are low in phosphorus, and hospitable in other ways to AM fungi (pH, etc), all of which is required for the rather finicky AM fungi growth (as extraradical mycelial network), reproduction and host root infections.
There are a few different 'types' of mycorrhizal associations which can vary between (inter-) Family, Genus, species and even intraspecies (aka “intraspecific”)[3]:
- Obligate mycorrhizal plant/tree/grass: Needs to achieve a mycorrhiza association for growth and reproduction (ie. “mycotrophic” relationship)
- Faculative mycorrhizal plant/tree/grass: Prefers to achieve a mycorrhiza association, but does not need to do so to survive, given sufficient 'available' soil phosphorus that is.[4]
- Non-mycorrhizal plant/tree/grass: self-explanatory
However, there is only one known 'type' of AM fungi, and that would be “obligate symbiont”[1]. AM fungi can not grow or reproduce without its' associated host plant root biomass for food (as special types of carbohydrates). The only exception I can think of is where a clone AM fungus has no mycorrhiza association and could 'fuse' (via. "anastomoses") with another clone AM fungus which has a mycorrhiza association, thus the first AM fungus clone could 'feed' off of the second AM fungus clone and the host plant it has a mycorrhiza association with. The caveat here is I'm not sure if that would happen. I have not researched AM fungi anastomoses too far, but I have yet to read of an instance I just described. In all cases I have read each AM fungus clone has its' own host plant with mycorrhiza association.
Not to mention plants which are mycorrhizal do not need to be infected to grow, and grow well. The plant just need the media bound microbes to breakdown organic amendments (nutrients like P) into forms available to the roots (via. Soil foodweb). Besides, even when a root system is 'fully' infected, which means infection of ~70-90% of total host root biomass within about the first 10 cm of media, the bio-chemical processes of the micro-herd will still provide P which the roots will adsorb, along with the P pipped directly into the roots by the AM fungi. If there is 'too much' available P in the media (organic or inorganic) the plant will use that P, and in turn AM fungi, and mycorrhiza associations are hindered.
(page 1, paragraph 2)
And they can bring about world peace! (j/k)
“[...]They make plant growth possible,[...]”. True in most cases, in nature. However, mycorrhizal plants/trees/grasses strictly make AM fungi growth possible. The fact is non-obligate mycorrhizal plants can grow without their associated AM fungi, however, the associated AM fungi can not grow or live without the host.
“[...]control the mix of plant species on the site,[...]”. Yes, however, this is in soils with high AM fungi biomass (spores, hyphae and mycelium (free and in mycorrhiza association to existing host roots)). In soils with low AM fungi biomass it's generally the plants/trees/grasses roots exudes which control much of the microbial biomass (micro-herd) within and immediately surrounding the rhizosphere. Colonizing soils which have low AM fungi biomass with AM fungi inocula to increase the AM fungi biomass is no easy task...and I know of NO professional horticulturist or botanist who would prefer to use freeze dried spores as AM fungi inoculum (which is the de facto standard for growing 'weed'). The standard is a *living* mix of hyphae, spores and infected host root biomass.
“[...]and dominate the microflora, selecting a soil full of “good bugs” when the site might otherwise fill up with pathogens.[...]”. That would be an accurate statement for soils rich in AM fungi biomass, like old-growth forests or prairie grasslands, not like soil tilled on a yearly basis, or soils with high clay or sand fractions. The plants/trees/grasses are in control of the micro-herd within the rhizosphere and immediate surroundings in many situations.
(page 1, paragraph 3)
I do not agree with this statement, it gives the value of AM fungi too much weight, in my opinion.
(page 1, paragraph 4)
That is an ambiguous statement. Does the author mean that Rhizobium spp. are N2 fixers? I hope not because they do not fix N2 I am aware of. Bacteria that fixes N2 (ex. Azotobacter spp.) also tends to fix N and are also 'free' in most cases, that is, non-symbiotic to host plants and can move around freely. Where Rhizobium spp. are generally 'fixed', that is, they have symbiosis with host plant roots and have limited mobility from host.
(page 2, paragraph 1)
FWIW, the current nomenclature of “actinomycetes” is “actinobacteria”. The reason being the microbe is a bacteria which exhibits fungal behavior.
AM fungi do in fact fix, and even *transport* (via. extraradical mycelium) nitrogen to host plants, along with absorbing and transporting P, S, Ca, K, Fe, Cu, Zn to host plant roots[5][6][7]. AM fungi not only aids in P and N uptake by the host, along with other minerals, but acts as a defensive barrier (via metabolites, enzymes, etc) against harmful microbes, protecting the host rhizosphere, along with providing an extended water resource (ie. pseudo roots), etc.
(page 3, paragraph 2)
I hope my corrections are a valuable contribution.
(page 4, paragraph 1)
Here are some good resources for the on-farm cultivation and use of AM fungi inoculum:
a) “Manual on Arbuscular Mycorrhizal Fungus Production and Inoculation Techniques”
Author(s): S.C. Miyasaka, M. Habte, J.B. Friday, and E.V. Johnson1
Departments of Tropical Plant and Soil Sciences and Natural Resources and Environmental Management
Soil and Crop Management, July 2003, SCM-5
b) “On-farm Production and Utilization of AM Fungus Inoculum”
Author(s): David D. Douds, PhD.
USDA-ARS Eastern Regional Research Center, June 16, 2009
c) “Appendix I. Checklist of steps for the on-farm production of arbuscular mycorrhizal [AM] fungus inoculum”
This appendix accompanies the article, “On-farm Production and Utilization of
AM Fungus Inoculum”, by David D. Douds Jr., USDA-ARS Eastern Regional Research Center.
d) “Arbuscular Mycorrhizas: Producing and Applying Arbuscular Mycorrhizal Inoculum”
Author(s): M. Habte and N.W. Osorio.
This book may be purchased from CTAHR; obtain an order form at:
http://www.ctahr.hawaii.edu/oc/forsale/AMFflier.pdf
(page 4, paragraph 6)
I disagree, and so do other researchers: [9][10][11], all papers are post-1990. In my opinion the term “colonization”, when referring to the penetration of the root by AM fungus, is inaccurate. Consider in mycology, when a fungus (ie. mycelium) is colonizing “something” it is so the fungus can “digest” that “something”. For example, when P.cubensis mycelium is colonizing compost it is doing so because the compost is the fungus food source. Most fungi 'eat', more like humans, though on the 'outside', than 'absorb' like roots. So following that rational, if an AM fungus “colonizes” the root of the host plant the AM fungus will 'eat' the root (eg. majically morph into a paraisitc fungi). And of course this is not the case. AM fungi absorb specialized host plant produced carbohydrates as main food source. Considering the plant which the AM fungus is symbiotic to is called the “host” plant, it makes sense to call the penetration by AM fungus as “infection”, not “colonization”. I have seen more instances of the term infection, than colonization...
(page 6, paragraph 1)
It's true that the mycorrhiza association, AM fungi spores, etc, need specialized microscopy equipment to view, but, media rife with AM fungi and well infected host root systems will surely make the AM fungi presence known by mycelium visible to the naked eye. If the media, or at least the rhizosphere has a good quantity of mycelium one could assume good infections rates.[7][8]
Use of a “brightfield” compound microscope (among others) enables one to rather easily identity whether or not the spore (or mycelium/hyphae) is in fact, AM fungi. Anyone reading this could do so with a ~$700.00 dollar microscope (comprable/better than the Lecia CME, ~>$1,500) and a few taxonony references.
Visable with the Naked Eye: AM fungi extraradical mycelium network extension outward:
(page 10, paragraph 2)
I think using the proper terms is wise, especially if the reader wishes to become an 'expert'. When the author writes “links”, he means the process of “anastomoses” (ie. fusing). It's important to remember that AM fungi of different genus and species co-exist in many soils. And there are many AM fungi isolates (aka strains) within a single species population. In most all cases two different “clones” of the same AM fungus strain, each infecting a separate host plant, will form two separate extraradical mycelium networks. When those two networks meet the “extramatrical hyphae” extending from both extraradical mycelium networks fuses to one another in the process of anastomoses. Think of it like conjoined twins. Once the two clones fuse they at that point essentially link their respective host plants to one another (but the connection is not direct). It is hard to underestimated the importance of anastomoses because it not only allows for the transfer of minerals, and other chemicals, but actually allows the exchange nuclei from each clone![7][8] [12] There are many who suggest once two clones form anastomoses they can 'communicate' with each other...whatever that means.
(page 27, paragraph 2-5)
...
QUOTE:
(note: live “propagules” (spores, hyphae/mycelium, infected host roots) are used for inoculum)
“Mixing inoculum into the potting media:
The next real decision-making step occurs when it is time to mix the inoculum into the potting media. There are two things to consider here: the potency of your inoculum, and the rooting volume of the cells in which the plants will be grown. Three years of on-farm production of AM fungi at 7 cooperating farms as part of a SARE grant yielded an average of 82 ± 20 propagules of AM fungi cm-3 (SARE grant LNE 03-179 final report). Propagule numbers averaged 503, 240, and 42 propagules cm-3 for the 1:4, 1:9, and 1:99 mixtures of yard clippings compost and vermiculite (Douds et al., 2006). Though this indicates only several cm3 of inoculum would be needed per planting cell to reach a target of 100-200 propagules of AM fungi per plant, it is very difficult to uniformly mix the inoculum into the potting media at a rate of only 1-2% by volume. We recommend utilizing the inoculum at a dilution of 1:9 or 1:19 (inoculum
otting media, volume basis). This comes as a result of an experiment conducted with 8 cultivars each of tomato and pepper. Plants were grown in a greenhouse for 4 weeks in 50-cell flats (70 cm3 per cell). Two sets of plants were grown in horticultural potting media: one amended with inoculum at a 1:9 and the other at a 1:19 (inoculumotting media, volume basis) dilution ratio. The initial, pure inoculum had a propagule density of 120 propagules cm-3. At the end of the experiment, tomato plants averaged 30.5% and 12.9% root length colonized by AM fungi for the 1:9 and 1:19 dilutions, respectively. Pepper averaged 14.8% and 8.0% root length colonized. All of these colonization intensities are sufficient to potentially produce a growth response. Choice between the 1:9 or 1:19 amendment would depend upon individual flat cell size. Cells that are 50 cm3 or smaller should be filled with media amended 1:9 with inoculum to ensure proper mixing and sufficient number of propagules.”[1][1] “On-farm Production and Utilization of AM Fungus Inoculum”
Author(s): David D. Douds, PhD.
USDA-ARS Eastern Regional Research Center, June 16, 2009
[2] “Manual on Arbuscular Mycorrhizal Fungus Production and Inoculation Techniques”
Author(s): S.C. Miyasaka, M. Habte, J.B. Friday, and E.V. Johnson1
Departments of Tropical Plant and Soil Sciences and Natural Resources and Environmental Management
Soil and Crop Management, July 2003, SCM-5
[3] “Adaptive significance of endomycorrhizas for herbaceous plants”
Journal of Russian Ecology
Volume 37, Number 1, January, 2006
[4] “Interspecific variation in plant responses to mycorrhizal colonization in tallgrass prairie”
Author(s): Gail W.T. Wilson and David C. Hartnett
Division of Biology, Kansas State University
[5] “External Hyphae of Vesicular-Arbuscular Mycorrhizal Fungi Associated with Trifolium subterraneum L. 3. Hyphal Transport of 32P and 15N”
Author(s): A. Johansen, I. Jakob Sen and E.S. Jensen
Plant Biology Section, Environmental Science and Technology Department,
Riso National Laboratory, DK-4000 Roskilde, Denmark
(Received 26 June 1992, accepted 13 January 1993)
[6] “The Biology of Mycorrhiza in the Ericaceae. IV. The Effect of Mycorrhizal Infection on Uptake of 15N from Labelled Soil by Vaccinium macrocarpon Ait.”
Author(s): D. P. Stribley and D. J. Read
Source: New Phytologist, Vol. 73, No. 6 (Nov., 1974), pp. 1149-1155
[7] “At the Root of the Wood Wide WebSelf Recognition and Non-Self Incompatibility in Mycorrhizal Networks”
Author(s): Manuela Giovannetti, Luciano Avio, Paola Fortuna, Elisa Pellegrino, Cristiana Sbrana, and Patrizia Strani
Department of Crop Plant Biology; CNR; UO Pisa; Pisa, Italy
Institute of Biology and Agriculture Biotechnology; CNR; UO Pisa; Pisa, Italy
Copyright © 2006 Landes Bioscience
[8] “The occurrence of anastomosis formation and nuclear exchange in intact arbuscular mycorrhizal networks”
Autor(s): Manuela Giovannetti, Paola Fortuna, Anna Silvia Citernesi, Stefano Morini and Marco Paolo Nuti
Dipartimento di Chimica e Biotecnologie Agrarie, Centro di Studio per la Microbiologia del Suolo, C. N. R., Università di Pisa, Via del Borghetto 80, 56124
Pisa, Italy; 29, March, 2001
[9] “Infection of Vesicular-Arbuscular Mycorrhizal Fungi to Plants and Spore Numbers in Cultivated Soils in Miyagi Prefecture”
Authoer(s): Kanehito Sansai
August, 31, 1992
[10] “Modeling arbuscular mycorrhizal infection: is % infection an appropriate variable?”
Author(s): Michael F. Allen
Mycorrhiza (2001) 10:255–258
[11] “Quantification of Active Vesicular-Arbuscular Mycorrhizal Infection Using Image Analysis and Other Techniques”
Author(s): S.E. Smith and S. Dickson
Department of Soil Science, Waite Agricultural Research Institute,
Glen Osmond, SA 5064, Australia.
Aust. J. Plant Physiol., 1991, IS, 637-48
[12] “Structure, Extent and Functional Significance of Belowground Arbuscular Mycorrhizal Networks Author(s): M.Giovannetti
Department of Crop Plant Biology, University of Pisa, Via del Borghetto 80, 56124, Pisa, Italy
Can you please quote the text from the paper you are referring to? I don't know what your writing about.
Thanks
Hi Lady,
Please see my second post in this thread. And note, in one great study by David D. Douds, Ph.D, the authors used BioBizz in one experiment.
Please see my second post in this thread. And note, in one great study by David D. Douds, Ph.D, the authors used BioBizz in one experiment.
P over ~225 ppm will probably hinder AM fungi to the point of making its' use a waste. Davd D. Douds, Ph.D has uses 210ppm of N in his experiments and even with that much N it was the concentration of P that effected the infection rates, where it needs to be ~=<20 ppm.
How so?
In my opinion that's not a good thing in most cases.
In all the studies I have read, as long as the media has about 20-35% air porosity and 5-15% water porosity (ie. pro-mix, etc), with decent bulk density and similar particle size (ideal from ~1/32" to 1/16" up to 1/8"), there will only be small pockets of anaerobic environments, which don't stay anaerobic long (drys out). However, the percent of anaerobic microbes in a 'good' media on average somewhere around 3-10% (or lower and from memory).
How so? The container generally has little to do with the anaerobic contents in media, apart from the important consideration of height vs width (eg. "perched water table") issues.
Cheers
Or just increase the media % air porosity, which for fibrous root like those of Cannabis spp. should be ~20-30%, minimum. With proper % air porosity and particle size, convection and the respiration of the aerobic media bound organisms (mostly bacteria) will add/remove gasses to/from the media...and save a bundle of dough and headaches
And adding a very high CEC powder like zeolite at ~3-6% of media by volume will reduce the ammonification by binding ammonia before it vaporizes. Also using calcidic lime instead of dolomitic lime is wise, along with high levels of humic acid. The interaction of Ca, humic acid and high CEC clay particles (eg. zeolite) creates the so called "clay-ca-humus aggregate". I sort of coined that term by adapting the methods/rational of "Luekbe Family" composting's term: "clay-humus crumb" (ala "Controlled Microbial Composting"). This aggregate will bind N among other minerals, etc.
Additionally, chemicals, enzymes, etc produced by the microbes will bind Ca with clay to form another type of aggregate which also binds N and other minerals, chemicals, etc.
Science is phun!
