[compost_tea] Re: Soil microbes and Round Up

From: Tim Wilson <thegoodjob_at_hotmail.com>
Date: Mon, 14 Mar 2011 00:36:45 -0000

The following interview is with another scientist, Don Huber, who recently =
retired from Purdue University, who has also documented negative environmen=
tal impacts from glyphosate.

The widespread use of glyphosate is causing negative impacts on soil and pl=
ants as well as possibly animal and human health. These are key findings of=
 Don Huber, emeritus professor of plant pathology, Purdue University.

Compromise agricultural sustainability, animal and human health

In a paper published in the European Journal of Agronomy in October 2009, H=
uber and co-author G.S. Johal, from Purdue's department of botany and plant=
 pathology, state that the widespread use of glyphosate that we see today i=
n agriculture in the United States can "significantly increase the severity=
 of various plant diseases, impair plant defense to pathogens and diseases,=
 and immobilize soil and plant nutrients rendering them unavailable for pla=
nt use." Further, the authors state that glyphosate stimulates the growth o=
f fungi and enhances the virulence of pathogens such as Fusarium and "can h=
ave serious consequences for sustainable production of a wide range of susc=
eptible crops." The authors warn "ignoring potential non-target detrimental=
 side effects of any chemical, especially used as heavily as glyphosate, ma=
y have dire consequences for agriculture such as rendering soils infertile,=
 crops non-productive, and plants less nutritious. To do otherwise might we=
ll compromise not only agricultural sustainability, but also the health and=
 well-being of animals and humans."

Please tell me about your research with glyphosate.
Don Huber: I have been doing research on glyphosate for 20 years. I began n=
oticing problems when I saw a consistent increase in "take-all" (a fungal d=
isease that impacts wheat) where glyphosate had been applied in a previous =
year for weed control. I tried to understand why there was an increase in d=
isease with glyphosate.

I found that glyphosate has an effect on reducing manganese in plants, whic=
h is essential to many plant defense reactions that protect plants from dis=
ease and environmental stress. Glyphosate can immobilize plant nutrients su=
ch as manganese, copper, potassium, iron, magnesium, calcium, and zinc so t=
hey are no longer nutritionally functional.

Glyphosate kills weeds by tying up essential nutrients needed to keep plant=
 defenses active. Glyphosate doesn't kill weeds directly but shuts down the=
ir defense mechanisms so pathogens in the soil can mobilize and kill the we=
eds. Glyphosate completely weakens the plant, making it susceptible to soil=
 borne fungal pathogens.

That is one reason why we see an increase in plant diseases. Glyphosate cau=
ses plants to be more susceptible and greatly stimulates the virulence of p=
athogens that kill plants.
How many plant diseases are linked to glyphosate?

DH: There has been a general increase in the number of plant diseases in th=
e last 15 to 18 years.
There are four primary soil fungi—Fusarium, Phythium, Rhizoctonia, and Ph=
ytophthora—that become more active with the use of glyphosate.
There has been an increase in take-all, Fusarium diseases, such as head sca=
b, Gibberella (Fusarium) in corn, Pythium, Corynespora or root rot in soybe=
ans, crown rot in sugar beets, and bacterial and fungal diseases. Fusarium =
head blight (which affects cereal crops) is a disease that produces a mycot=
oxin that could enter the food chain.

There are more than 40 diseases reported with use of glyphosate, and that n=
umber keeps growing as people recognize the association (between glyphosate=
 and disease).
Has research confirmed the link between glyphosate and Fusarium?

DH: There is plenty of data to show that, and it raises concerns about toxi=
ns in food.

Can you give an example of a specific crop that has been negatively impacte=
d by glyphosate?
DH: Last summer I visited farms that had typical glyphosate damage. I recei=
ved a call from a potato seed farmer in Minnesota who grows 1000 acres of s=
eed potatoes. There was so much glyphosate in the potato tubers from a prev=
ious crop of Roundup Ready soybeans that the potatoes can't be used as seed=
 and could not be certified.

Proponents of glyphosate say it is environmentally benign. Would you agree =
with that assessment?
DH: Absolutely not. That's an outright mistaken notion. Glyphosate is the s=
ingle most important agronomic factor predisposing some plants to both dise=
ase and toxins. These toxins can produce a serious impact on the health of =
animals and humans.
Toxins produced can infect the roots and head of the plant and be transferr=
ed to the rest of the plant. The toxin levels in straw can be high enough t=
o make cattle and pigs infertile.

In your paper you say that "the introduction of such an intense mineral che=
lator as glyphosate into the food chain through accumulation in feed, forag=
e, and food, and root exudation into ground water, could pose significant h=
ealth concerns for animals and humans and needs further evaluation." Could =
you elaborate on this?
DH: Micronutrients such as manganese, copper, potassium, iron, magnesium, c=
alcium, and zinc are essential to human health. All of them can be reduced =
in availability by glyphosate; mineral nutrients are less in glyphosate tre=
ated plants. We are seeing a reduction in nutrient quality (in food crops).=
 
There are also reports of allergic reactions, such as stomach lesions, prod=
uced by the Roundup Ready (genetically modified) gene.
These reactions need to be studied; there needs to be a lot more informatio=
n that we don't have. This type of research has been prevented by a lack of=
 access to information.

What other impacts do you see caused by the Roundup Ready gene?
DH: The gene will reduce micronutrient efficiency up to 50% for zinc and ma=
nganese. It's very significant unless the plant is supplemented with micron=
utrients. This could also account for the yield drag (reported with Roundup=
 Ready crops).
Unfortunately, most researchers are forbidden to do work in the area. They =
don't have access to isogenic lines (conventional and Roundup Ready plant l=
ines that are otherwise genetically identical); the materials are denied to=
 researchers.

In your paper you recommend using as small a dose of glyphosate as possible=
. Why is this?
DH: To my knowledge we've never had this much reliance on one herbicide. It=
's hard to find an acre in the US that hasn't had glyphosate applied on it =
in the last three years.
We need to have judicious use of glyphosate and remediate the damage that i=
t does. If we continue to abuse the use of glyphosate, it's just a matter o=
f time before we see more serious negative ramifications. We will have incr=
easing toxin levels (in crops), reduced nutrient values, and the direct pre=
sence of glyphosate in crops.
There are a lot of serious questions about the impacts of glyphosate that w=
e need answers for in order to continue using this technology. I don't beli=
eve we can ignore these questions any more if we want to ensure a safe, sus=
tainable food supply and abundant crop production.
(Copyright The Organic & Non-GMO Report, May 2010)



--- In compost_tea_at_yahoogroups.com, "Dan" <dansquest2005_at_...> wrote:
>
> Hi Group,
> I was wondering as a home gardener if anyone had done a quick look thro=
ugh their microscopes to see if Round-Up had had any effect on soil microbe=
s or know of research that has been done on this subject.
>
> Dan in Ct Zone 6A
>




Received on Sun Mar 13 2011 - 20:44:10 EDT

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