Released April 29, 2008

STILLWATER, Okla. -- Oklahoma producers need to “make their cotton crop” at the front end of the growing season.

That is part of the message recently presented to cotton producers from across Oklahoma’s cotton growing region by J.C. Banks, Oklahoma Cooperative Extension Service cotton specialist.

Although it may sound counter-intuitive, for cotton the growth period before blooming will determine the yield potential of the crop. At the first bloom, 80 percent to 90 percent of the crop that will be harvested is already on the plant.

“The ideal cotton plant develops the boll load early, down in the plant,” he said. “That boll load serves to regulate the growth of the plant. The activity and growth of the plant after the first bloom helps to determine final yield and quality.”

One tool that producers can use to help manage the growth of the cotton plant is a mepiquat chloride-based plant growth regulator.

“Mepiquat chloride can help reduce the internode length, the distance between fruiting branches; it helps restrict vegetative growth, increases leaf thickness and concentrates the production of chlorophyll,” Banks said. “All of that can help reduce plant size making for easier harvest with less lodging and boll rot.

Banks said while the product can sometimes increase yield, it should not be applied for yield enhancement because that is not a guarantee.

“I like to say it could be a bonus,” he said. “Plant mapping, the tracking of plant growth stages, can help growers most effectively plan the best strategy for using mepiquat chloride pre- or post-blooming stage.”

Techniques such as average internode length, nodes above white flower, and internode length of the fourth noted from the top to the plant can be used to make decisions on the rate and timing of application.

“One thing I stress is that no grower should use the chemical in any sort of ‘automatic application’ process,” Banks said. “It’s important that a grower knows the chemical is needed before applying it, and then make sure it’s applied at the proper rate. It should never be used on drought-stressed cotton. That just serves to doubly stress the plant.”

Additional information on the use of mepiquat chloride can be found on the North-Texas-Oklahoma-Kansas cotton Web site located at http://www.ntok.cotton.org as well as http://www.osu.altus.ok.us, the Web site for the Oklahoma State University’s Southwest Research and Extension Center in Altus.

“Producers are also welcome to drop by the center, e-mail us or call us,” Banks said.

The center is located on U.S. Highway 283, about three miles south of downtown Altus. The phone number is (580) 482-2120.

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http://www2.dasnr.okstate.edu/Members/donald.stotts-40okstate.edu/early-growth-key-to-cotton-yield

Contact: Ron Dahlgren, (405) 744-3737, ron.dahlgren@okstate.edu