Cotton variety breeding research in Arizona is producing improved varieties with increased profit potential tied to increased yields, improved heat tolerance, and lower micronaire, according to Randy Norton, resident director of the University of Arizona's (UA) Safford Agricultural Center in Safford, Ariz. While Arizona growers would see the greatest benefit, other growers across the Cotton Belt also stand to profit.

Norton is testing new germplasm in three locations on two fronts: advanced strain testing for seed companies, plus preliminary and advanced strain testing for the Arizona Cotton Growers Association's (ACGA) breeding program.

Seed company advanced strains testing

Testing up to 10 lines per company, Norton places proposed varieties under the field microscope at the University of Arizona's agricultural centers in Safford, Maricopa and Yuma, Ariz.

“It provides us with a unique look at these experimental lines across varying environments,” Norton said. Safford stands at 3,000 feet above sea level, Maricopa sits at 1,100 feet and Yuma kneels at 100 feet. “It's interesting to look at these across the environment because they vary quite dramatically. A lot of lines that we put into our advanced strains testing are not very heat tolerant in Maricopa but work better in Safford.”

In 2006, the UA planted and studied advanced strains from Salcot, PhytoGen, Delta and Pine Land Company, Stoneville, California Planting Cotton Seed Distributors which is being purchased by Bayer CropScience, United Agri Products, FiberMax and the ACGA. The companies paid for the independent research, an up close review of fiber quality, yield potential, and other factors in the different varieties.

“To the grower, yield is the bottom line but fiber quality is becoming increasingly important in marketing cotton. The vast majority of U.S. cotton goes overseas and buyers are demanding certain qualities of cotton. We must provide that to remain competitive,” Norton explained.

He called Arizona a state long used for seed production because of high yields and planting seed quality. The goal — the UA's data will help seed companies make decisions on which varieties will be moved to market, Norton said.

“The advanced strains testing gives us the opportunity to evaluate lines before they are released commercially,” Norton added. “We are seeing some good new varieties coming down the line. Several varieties in our tests last year went commercial and were planted in significant quantities across Arizona.”

While micronaire problems have been an issue in past years, Norton credited seed breeders for developing varieties with lower micronaire. “Arizona was having problems with high micronaire. To the breeders' credit, varieties were developed not in the discount range for micronaire experienced as in the past.”

Variety evaluations are also conducted in a small plot experimental design at the three agricultural centers: in Safford by Norton, in Maricopa by Extension specialist Pat Clay, and in Yuma by Extension's Eric Norton and Kurt Nolte. The UA also conducts statewide Upland cotton variety testing on 11 large-scale trials on grower cooperator fields. Seed companies can enter up to three varieties.

“The main point of what we're doing is allowing Arizona growers to get a look at the lines in an advanced strains environment before commercial release and hopefully provide them with varieties coming down the pike,” said Norton. Advanced strains are lines of experimental lines of cotton not yet released for public use.

While test lines are developed for Arizona, some lines may travel across to other Cotton Belt states. A lot of the varieties that perform well in the low desert can have good results in other areas but not always, he noted.

Preliminary, advanced strains testing

The ACGA launched its cotton-breeding program in 2001 under the leadership of Stanfield, Ariz., grower Bill Scott, who has been the leader in developing more varieties suited to Arizona through ACGA.

Cotton grower Paco Ollerton of Casa Grande, Ariz., who became the breeding committee co-chair with Scott in 2001, said the ACGA effort has moved forward in developing higher yielding varieties for Arizona.

According to Ollerton, the ACGA created its breeding program because the organization was not satisfied with the staple, micronaire, and fiber strength in available commercial varieties.

“We felt that everything being bred was for a different type of the world. We in Arizona were kind of a dinosaur,” he stated. “There were millions of acres in Texas, the Southeast, and the Delta which had good varieties. We felt that Arizona was just a nursery or greenhouse and the companies weren't breeding for us. Nobody cared about our issues.”

Norton is in his second year of evaluating the ACGA varieties for yield and heat tolerance. His research is ACGA funded.

“What I am observing is higher yields on some of the preliminary strains from ACGA when compared to some of the yields in the advanced strain trials,” said Norton. “In fiber quality, many preliminary trials have superior quality compared to advanced strain lines. Not every variety is like that. Some are doing well and some are not.”

“In 2007 we have plans to expand the ACGA preliminary testing program into Safford,” Ollerton announced. “It would be 2008 before we can put something in a bag. We have a couple of lines. It will depend if the data and yield information are promising.”