( s are expensive and often only provide ...)Scientists seek useful traits in wild cottons

Arnold raises thrips on wheat, a favorite host plant, and forces them to move to neighboring cotton plants by killing the wheat with herbicide. "This produces massive thrips pressure on the cotton plants, and results in a lot of damage to those first four true seedling leaves," he said. "We measure the leaf damage, identify cottons that show thrips resistance and subject those to further tests."

Sheehan raises Lygus bugs, a secondary pest of cotton, and confines their feeding to certain parts of cotton plants using bug cages. The amount of damage they inflict on cotton fruit and their ability to lay eggs for another generation are good indicators of Lygus resistance, said Sheehan, who hopes to intensify her experiment in 2007.

Raina King, a Texas Tech University graduate student, is working to develop 'cleaner' cottons that shed the small leaves (bracts) at the base of each boll a few days after flower blooms open.

Determining whether this trait is dominant, co-dominant or recessive and finding its DNA location could help breeders develop upland cottons that require less lint cleaning ?producing cleaner fiber with less ginning costs, Gannaway said.

Scientists at the Crops Genetic Research Facility at Lubbock have been conducting their cotton research since 2004. The facility was completed and came on-line in 2003.

"We have developed several reliable methods for screening obsolete and wild cottons for several positive, heritable traits," Gannaway said. "The data from these experiments should give molecular breeders more tools to work with as they look for ways to diversify, improve and expand our cotton gene pool. That will benefit global breeding stocks and lead to varieties that are more flexible and productive."
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Source:Texas A&M University - Agricultural Communications