The good news about the lack of genetic diversity in cotton is that the perceived paucity may be imprecise.
“It's not as big a problem as many perceive it to be,” said John Gannaway, Texas A&M cotton breeder, who plies his trade at the Research and Extension Center in Lubbock.
Gannaway addressed the misconception during the recent Southwest Crops Production Conference and Expo at Lubbock.
The implication that the cotton gene pool was a bit shallow first came from the textile industry, Gannaway said.
“The textile folks said they didn't have enough varieties and fiber qualities to choose from. We'd always heard that they really needed consistency. But they blamed farmers for not growing more varieties. He said growers insisted that they grew what was available.
That left cotton breeders, he said, “Because there was no one else to blame.”
Gannaway said a sub-plot of the intrigue implied that the rapid development of transgenic varieties added little to the gene pool. “Value-added traits came from back-crossing, not forward crossing,” Gannaway explained. “That was a concern.”
But breeders have a tremendous amount of material to work with, collected primarily in three locations, College Station, Texas; Montpelier, France; and Russia.
“We have 78 different countries represented in the College Station collection,” he said. “We have cotton from as far as 45 degrees north to 38 degrees south. That's a big swath.”
The collection includes 2531 varieties. “We have more than 2000 wild diploids and tetraploids. Our commonly planted cotton varieties are tetraploids. It's difficult to cross tetraploids with wild diploids, but it can be done.”
He said some selections are able to extract salt from the soil and store it in leaf tissues. “Salt tolerance should be possible with these kinds of traits,” he said.
He said diversity exists. “We have to put that diversity into a usable form.”
He has a wish list of cotton variety traits he'd like to see identified or improved. They include: drought, salt and cold tolerance; disease and insect resistance; and fiber and seed property improvements.
“It takes a lot of time to get the facilities, the people and money just to get started,” he said. A recently completed greenhouse at the experiment station at Lubbock is a good start. He also has some seed money and a staff in place.
“We have some good people. Leslie Wells, the facility manager is one. If it can be grown, Leslie can grow it. Monica Bellow will concentrate on insect screening, focusing on lygus.
“Bryan Henson will work on insect resistance, primarily looking at aphids. Anna Hall will work on drought and salt tolerance.”
Gannaway said these, plus other research center scientists interested in cotton will make certain cotton has adequate genetic diversity.
“Once we identify the traits we want, we'll incorporate them into our breeding materials for use by public and private breeders,” Gannaway said.
Farmers will be beneficiaries, as well as those textile mill buyers who perceive a genetic diversity problem.