New Process Keeps Biocontrols Alive
Dozens of fungi and bacteria have been tested and found effective for
controlling weeds that infest crops and rangeland. Unfortunately, most haven't
made it out of the laboratory.
Often it's because the weed-killing microbes can't be kept alive or
effective for the long-term. Stabileze (pronounced stable-ease), a new process
invented by Agricultural Research
Service scientists, could change that.
"Our method uses sugar to stabilize the cell membranes of the
organisms," says Paul C. Quimby, Jr. He is a plant physiologist at the ARS
Northern Plains Agricultural Research Laboratory in Sidney, Montana. "This
approach keeps a large percentage of the organisms alive for 6 weeks to 6
months at room temperature and for at least 2 years under refrigeration,"
Now, some organisms can only survive a few hours without the formulation.
The sugar solution and microbes are mixed in a food processor with silica,
corn oil, and another ARS invention a water-absorbent starch known as Super
Slurper. The mixture forms dispersible granules that can be applied to foliage
with conventional spraying equipment. Another plus: the ingredients are cheaper
and easier to work with than the sodium alginate and calcium salts that are
commonly used to make similar granules.
ARS has received patent application No. 08/695,249 on the process. Quimby
developed Stabileze with ARS plant pathologist Anthony J. Caesar; former ARS
botanist Jennifer L. Birdsall, who now works for USDA's Forest Service; ARS
chemist William J. Connick, Jr.; ARS plant pathologists Clyde D. Boyette and
plant pathologist Nina K. Zidack; and plant pathologist William E. Grey, who is
at Montana State University in Bozeman.
Ideally, commercial manufacturers and users would like a 2-year survival
rate at room temperature, to save on refrigeration costs. But Stabileze is a
step in the right direction. By Kathryn Barry Stelljes.
Plains Agricultural Research Laboratory, P.O. Box 1109, Sidney, MT 59270;
phone (406) 433-2020
Utilization Research Unit, P.O. Box 19687, New Orleans, LA 70179; phone
Boyette is at the USDA-ARS Southern Weed Science Laboratory, Stoneville, MS
38776; phone (662) 686-5217.