Is it a glyphosate-related problem?
A devastating disease called black root rot is spreading throughout the Louisiana GM soybean crop.
We've received a comment on the report below from a researcher who wishes to remain anonymous. The researcher says the problem is much worse than the story indicates. The researcher believes it is caused by glyphosate residue in high clay content soils. The glyphosate is very persistent and slow to degrade in the high clay soil.
Unfortunately, now that the vast majority of soybean production in the US is Roundup Ready, there is no significant control population of non-GM soybeans not doused with glyphosate to compare with the sickly population. This also enables the pro-GMO lobby to deny it's a GM or a glyphosate problem.
Scientific research showing glyphosate applications cause or exacerbate plant diseases:
Black root rot suspected in Louisiana soybeans
LSUAgCenter.com, 7 August 2014
Soybean growers in Louisiana are seeing soybean damage this year that LSU AgCenter scientists believe has been in cotton for many years.
Black root rot is a fungal disease that lives in the soil. And with minimum tillage or no-till situations in soybeans its presence can increase, said Trey Price, LSU AgCenter plant pathologist.
“In 2009, the disease was described as a disease of soybeans in Arkansas and has been mentioned as an issue in Mississippi over the past several years,” Price said.
Recently, Price has been receiving phone calls from growers about this problem, and he has made numerous field visits to inspect damage from the pathogen believed to be causing it.
“This disease started showing up here about five years ago, and we called it a mystery disease,” Price said. “The suspected causal agent is Thielaviopsis basicola, which has primarily been described as a seedling disease of cotton.”
Price said he is seeing the disease more than ever this year, and he believes it is more prevalent in fields that are continuously planted in soybeans.
With corn prices low and soybean prices a bit more steady right now, growers are less likely to rotate their fields. This pathogen is able to survive on plant residue, and build up in the soil, he said.
“Right now, I would say that it’s a minor issue overall.” Price said. “However, there are some fields where the damage can be anywhere from 5 to 10 percent.”
The pathogen causes black root rot in cotton, thus the name used in soybeans. Price said work is being done to determine the effects of fungicide seed treatments. Right now he’s not sure of varietal susceptibilities.
“At this time we don’t have the data to prove that rotation with corn helps,” Price said. “But I have seen a decrease in the presence of the disease where soybeans have not been continuously planted.”
This pathogen has been around for a long time. It survives in the soil and has a very large host range, he said.
“It really isn’t a very serious problem, but we want the growers to know that it is out there,” Price said.
Additional information on this disease is available at LSU AgCenter parish offices.