08/22/1995

Drought, Insects Main Topics of AU Field Day in Prattville

PRATTVILLE, Ala. - Nearly 100 cotton producers and agri-business leaders from the Prattville area saw the latest in cotton insect and weed management research and heard a dire statewide outlook for this year's drought-plagued crop during a Cotton Field Day at the Prattville Experiment Field here.

The field day, co-sponsored by the Alabama Agricultural Experiment Station and Alabama Cooperative Extension Service at Auburn University, featured scientists from Auburn University who explained many of the ongoing experiments at the 80-acre research facility.

AU researcher Mike Patterson noted that results of a defoliation test may not be very applicable this year because of the drought. In tests with various defoliants and the boll-opener Prep, researchers found no reduction in quality. The benefit of more uniform picking and once-over picking made possible by Prep provide growers an opportunity to reduce harvest cost without reducing fiber quality, according to Patterson.

"Unless our dry conditions end, growers won't need Prep. But, if we get enough moisture to help cotton put on a top crop of bolls, Prep could by critical in improving yield," Patterson concluded.

In weed control tests, both Buctril resistant (BXN) cotton and a new, ultra low rate herbicide, Staple, performed well on some weed species.

BXN cotton includes a gene that makes it tolerant of Buctril, which would immediately kill cotton without the gene. Researchers recorded excellent control of cocklebur, velvet leaf, and morningglory with BXN cotton, but Buctril is weak on sicklepod. Staple provided similar results, but was also weak on sicklepod control. By adding Cotoran to either Staple or Buctril-treated BXN cotton, researchers added excellent sicklepod control.

AU researcher Dale Monks gave the cotton producers an update on this year's cotton crop statewide. "Here in central Alabama we've seen all the pest problems found in other parts of the state, plus we have had to deal with a severe drought. In north Alabama drought hasn't been a major obstacle, but the highest concentration of budworms ever recorded has put the Tennessee Valley crop in peril. In south Alabama neither insect problems nor drought were severe and many growers looked to produce 2 to 2.5 bales per acre. Then Hurricane Erin came, and now many fields are a total loss," Monks explained.

A highlight of the meeting was an update on bt cotton, which includes a gene that carries the bacillus thuringiensis virus. The combination of heavier than normal budworm moth flights and resistance by the insect to once effective insecticides have caused growers to look more to biological control methods. In tests at the Prattville Field, AU researcher Bill Moar noted that BT cotton has performed well against tobacco budworms, but has had little impact on beet armyworms. "We are now looking at some methods to increase the longevity of bts. Currently, they may last only a day or two, and with heavy pressure, that sometimes isn't enough to keep worms under control," Moar noted.

Extension cotton specialist Ron Smith told the cotton producers that this has been a year for the record books in terms of insect damage. "I had a call from a grower in the Florida panhandle who said some large insects were eating his cotton. When I looked at the crop, I couldn't believe it--catalpa worms were feeding on cotton leaves. We've also seen marsh caterpillars, cotton square borers and other pests either in larger than normal numbers or at strange times of the season," Smith concluded.

"I'm glad to see so many growers come out to our meeting, but I wish they were here under better circumstances. We've faced the same overwhelming insect pressure and heat and drought that they have had to deal with, so I can understand the need to find some answers. Hopefully, some of the genetic work or other production techniques will help growers better cope with these problems in the future," lamented Don Moore, superintendent of the Prattville Field.

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News from:

Office of Ag Communications & Marketing

Auburn University College of Agriculture
Alabama Agricultural Experiment Station
3 Comer Hall, Auburn University
Auburn, AL 36849
334-844-4877 (PHONE) 334-844-5892 (FAX)

Contact Jamie Creamer, 334-844-2783 or jcreamer@auburn.edu
by Roy Roberson

August 22, 1995