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growingdeeprootsorganicly
11-22-2008, 02:41 PM
lately i've been doing alot of research/studying about the usefulness/harm from using single species compared to using a wide diverse community of organisms for disease,insect prevention,regulation/nutrient cycling/nutrient retention/soil building/plant growth improvement/ete.

i bring this topic up to broaden my own personal understanding on the subject and to bring out discussion from the forum. this thread is not intended to discredit or bash single or multi-mono culture microbial products in anyway.

my first feeling on the subject is that mono cultures depending on the species could already be present at site/soil/leaf?

if not present at site and not local to area could there be a competition/unbalancing issue depending on situation if used regularly?

single species organisms have a "window" lets say that they grow in...right environment,temp/moisture/ph/food/other micro's in area?........if condition's aren't right or since they change through out the year,how can these products compensate for environmental changes and still provide benefit since there is no diversity in the microbial community to adapted to changes if it's a product intended for plant growth in a closed system?

since it's up to the plant what organisms it wants, out of the thousands/millions/billions? of DIFFERENT species in soil/above round....
..how can these mono cultures inoculate/benefit any given plant in any given soil/climate in an out door open system?

healthy soil microbe community's have thousands and thousands of diverse species doing different things at different times... all working together?
what impact/harm/benefit can using a single species in a diverse environment like that?

insect control,disease control seems like a perfect place's for mono cultures,
since a specific microbe or better yet specific microbe's can produce substances to combat these SPECIFIC issues.
but can these off set balance in the soil since they will find their way there?
since these type of products work by preventing wouldn't a well made diverse community CT be safer/better for the site issue



here are a few things i pulled from doc I's books on the subject

Adding biology page 50 titled Diversity of microorganism community essential.

A wide diversity of species of each functional group is needed because the environment,at any given time,selects for the growth of a very LIMITED set of those species.The environmental conditions will be right for some species of organisms to be working,while others will be asleep.A few to SEVERAL hundred will match the growth conditions at any one moment,so THOUSANDS of species of each functional group are needed. The PLANT selects and FEEDS those organisms that prevent disease around it's roots,leaves,stems,ete. Beneficial species for each set of conditions through out the year,then disease or pest cannot get established. DIVERSE sets of organisms will out compete disease pathogens and pest for food and space.

same book referenced page 62 titled, Single species inoculants

Applying a single bacteria species to control a specific problem OFTEN does not succeed because environmental conditions and plant requirements may not favor the growth and survival of that particular single species.
DIVERSITY is essential for the organisms to work together in the right BALANCE.

same page 62 ....Trichoderma

trichoderma may ward off a certain problem,disease or pest-but will also compete with other non-aggressive BENEFICIAL organisms for food and space,creating the same IMBALANCED system that exists in chemically treated non-biological systems. in addition, if there is another problem that the trichoderma species cannot handle,there are not enough other types of beneficial species left that can effectively treat this new situation. If it is necessary to treat disease out break that a single species inoculum such as trichoderma can handle,we recommend adding those microbes during that disease outbreak ONLY. when the outbreak is under control, Add back a DIVERSE set of beneficial organisms that where lost.

same book page 63 Bacillus....last sentence

only use a single species inoculum if you know what environmental conditions that particular species requires,and IF it can perform the function you want under those conditions.


Doc I's......The field guide 1........page34 title Single species inocula

The single species inocula can be useful, if you know the precise thing you want to control, know that you are buying the CORRECT environmental isolate that will grow in the conditions in your soil(ie. temp,moisture,humidity,ete are right for it to grow) this can be extremely specific. You should also know if you already have the beneficial organism in your soil/compost/CT, so you know if you need to add it.



to sum this all up... the reoccurring theme i get from Elaine is diversity for plant growth and disease and pest protection unless you need specific cultures to fix specific problems and then reintroduce a diverse microbe community back to leaf/soil?
what are your thoughts guys?

JDUtah
11-22-2008, 06:06 PM
my first feeling on the subject is that mono cultures depending on the species could already be present at site/soil/leaf?

if not present at site and not local to area could there be a competition/unbalancing issue depending on situation if used regularly?

single species organisms have a "window" lets say that they grow in...right environment,temp/moisture/ph/food/other micro's in area?........if condition's aren't right or since they change through out the year,how can these products compensate for environmental changes and still provide benefit since there is no diversity in the microbial community to adapted to changes if it's a product intended for plant growth in a closed system?



My opinion is to stick to natives from the soil/area. Native plants, native soil microbes.

Only use local compost that has been inoculated with only local soils. If you are focusing on introducing microbes specifically, microbes bred out of local compost or soil.

Scientific American did a show (http://vvi.onstreammedia.com/cgi-bin/visearch?user=pbs-saf&template=play220asf.html&query=%2A&squery=%2BClipID%3A5+%2BVideoAsset%3Apbssaf1204&inputField=%20&entire=No&ccstart=2626860&ccend=3296129&videoID=pbssaf1204) about how spores from a common soil fungi (one of the species that can cause brown patch) blow 4,000 miles from farmland in Africa and kill coral in the Bahama's during drought years. I like what Allen Alda said about it...

"Alien species can behave in unexpected ways in a new environment."

If we start playing God too much by manufacturing, exporting, importing, and introducing microbes into environments that are not balanced for them... we do not know what we are doing = "Algae blooms organic style."

Stay local... turn waste into use... and we should do minimal damage.

As far as fungal pest control... if only a company could sell a regulated natural chitinase. Spot treat the affected areas. Then when killed, re-inoculate the "dead soil" with microbes bread out of untreated soil from the same area. Unfortunately, currently, only chitin is sold... no farmed chitinase.

But that's just my ever evolving .02

David

JDUtah
11-22-2008, 06:18 PM
Edit: I think I was misled about the spore causing brown patch.

Kiril
11-22-2008, 06:28 PM
Don't need a bunch of scientists to tell me that diversity is better .... it is (or should be) common sense. Beyond the historical evidence of our own ignorance, diversity has always been natures way. Why is there a need to state (or restate) the obvious? I find myself amazed at "our" presumption that we know better than nature, or even worse, that we can improve on it. :hammerhead:

JDUtah
11-22-2008, 06:58 PM
Don't need a bunch of scientists to tell me that diversity is better .... it is (or should be) common sense. Beyond the historical evidence of our own ignorance, diversity has always been natures way. Why is there a need to state (or restate) the obvious? I find myself amazed at "our" presumption that we know better than nature, or even worse, that we can improve on it. :hammerhead:

I mostly agree. I believe that we should learn to trust nature.

However, I might be reading Kiril’s post wrong, but about diversity... the context of the thread is diversity for pest control (mostly?).

It is a form of biological pest control. Even microbes for fertillity should be treated as biological pest control...

History has taught us that biological pest control needs to be VERY specific and species targeted. We need to know exactly what species we are trying to remove, and we need to know exactly what effects our introduced species will have on ALL organisms (pests and non pests). Otherwise we can cause more harm than good.

So in context of biological control of disease (treatment or prevention) I believe a very specific and thorough understanding of the control species and the environment is absolutlely nessesary.

To me, shot-gunning a huge diversity of microbes in an effort to suppress and discourage disease is extremely risky. It would be like introducing thousands of species of beetles to an environment hoping that one of them takes care of the problem... well what if one of those species is parallel to the 'Emerald Ash Borer', and we just don't know it yet?

In some cases, biological pest control can have unforeseen negative results that could outweigh all benefits. For example, when the mongoose was introduced to Hawaii in order to control the rat population, it preyed on the endemic birds of Hawaii, especially their eggs, more often than it ate the rats.

Cane toads (Bufo marinus) were introduced to Australia in the 1930s in a failed attempt to control the cane beetle, a pest of sugar cane crops. 102 toads were obtained from Hawaii and bred in captivity to increase their numbers until they were released into the sugar cane fields of the tropic north in 1935. It was later discovered that the toads can't jump very high so they did not eat the cane beetles which stayed up on the upper stalks of the cane plants. The toads soon became very numerous and out-competed native species and became very harmful to the Australian environment, including being very toxic to would-be predators such as native snakes.

Forgive the wiki (http://en.wikipedia.org/wiki/Biological_pest_control#Negative_results_of_biological_pest_control)


The complexity and current ignorance of soil life makes me reluctant to support any form of microbial biological control for soil/turf diseases.

Like Kiril said, we need to stop thinking...
"that we know better than nature, or even worse, that we can improve on it."

CkLandscapingOrlando
11-22-2008, 07:21 PM
For the most part all of you have said about the same thing as the writer.You just did it in normal talk.The soil has to be balanced.To much of on may hurt the other which inturn leaves a weak point.If you find that you need to add some thing to take care of something,you then must rebalance the soil after that something has been fixed.The whole idea is that if a plant is growing in its natural conditions with a natural balance of organisims,then they dont typicaly need help.Like how asian scale is killing the sagos in florida at a scary pase.Out side of its natural area there are no ways to natrualy combate the pest.Nothing eats it.In asia its in check do to natural pest.Besides once you put something on a synthetic program it becomes a crack head.Let trugreen stop spraying a lawn and you'll see how fast it goes to crap without help

phasthound
11-22-2008, 07:32 PM
Let trugreen stop spraying a lawn and you'll see how fast it goes to crap without help

Or let them continue spraying and still watch it go to crap.

JDUtah
11-22-2008, 07:36 PM
"Or let them continue spraying and still watch it go to crap."

lol

ICT Bill
11-22-2008, 07:59 PM
Growing, excellent subject. We will get as many different answers as there are microbes in your back yard
Peer reveiw stuff: the scientists take very isolated single strain microbes and test them against controls. Does it promote growth or fight pathogens, the end result of testing will tell. But in a very limited and sterile environment

Elaine: If you believe most of what Elaine says, and I have no reason not to, she tells us that 99.9999 percent of the biological activity between soil and plant cannot be cultured and categorized. Okay that means the scientist have a full time job for a long time

General knowledge: there are single strain inoculums that have proven to be effective against certain fungal diseases, pythium and trichoderma harzania T22 works effectively most of the time. bacillus subtillis work effectively to reduce fungal pathogens, I believe Tad Hussey made a statement recently that when added to brews, fungal numbers decreased quite a bit.

Did you notice the trich reference "trichoderma harzania T22" this is a certain DNA sequence of a certain microbe. to say "trichoderma" as a general statement is like saying "the automobile industry" I happen to drive a 1994 318is BMW, how does "auto industry" define my car?

I am not being negative here, I am pointing out the scope of the conversation

there are more bugzzzz in the soil than we can know at this point, their interaction is an educated guess in most instances. we do have evidence that certain species help certain outcomes though

Mycorrhizae fungi for instance, most believe they are beneficial and there are many studies that show this certain strain helps this plant do better and grow better

this is a very broad subject that we should continue and continue to learn from, I am going out to dinner, more later

Smallaxe
11-23-2008, 10:26 AM
Healthy soil environment = healthy microbes thriving.

High N inputs and overwatering doesn't equal healthy balanced soil.
Lots of built in balancing strategies already in places.

Learn the strategies and the names and functions of 5400 different speices in various population densities in comparison to the others in certain conditions of water, weather,etc, becomes less important.

Bill , that scientific study will never have a usable result. Too many factors on too many species and it changes in the soil constantly.
We can't even know for sure that ct shipped from the South brings balance to the soil in the North even though it seems to work.

tadhussey
11-25-2008, 03:08 PM
bacillus subtillis work effectively to reduce fungal pathogens, I believe Tad Hussey made a statement recently that when added to brews, fungal numbers decreased quite a bit.



Just wanted to clarify, that this was not a qualified study, but rather our own observation through brewing identical compost teas with one containing Serenade (commercial name for the bacillus subtillis we've been discussing). Testing with done through SFI. We found our fungal numbers significantly reduced, therefore we made the decision that it was not something we wanted to add to our compost teas. If you're looking for a balance of diversity and creating a nutrient cycling ecosystem similar to that found in soil (albeit more concentrated), then adding high concentrations of a particular species could disrupt this process.

growingdeeprootsorganicly
11-25-2008, 03:25 PM
does anyone have any study on the negative effects on mycorrhizal fungi spores/colonization from the repeated use of products containing mono culture of bacillus subtillis and trichoderma genus?