Technology Reduces Gossypol in Cotton Seed
January 12, 2007
Genetic technology developed by
Agricultural Research Service (ARS)
scientists and cooperators suggests that cottonseed could one day become a
significant source of low-cost protein for the developing world.
The research team, headed by Keerti Rathore at the
Institute for Plant Genomics and
Biotechnology, Texas A&M University,
and ARS chemists
D. Stipanovic and
S. Puckhaber in College Station, Texas, found a way to genetically reduce
the amount of the natural toxin known as gossypol in cottonseed.
Stipanovic and Puckhaber are with the ARS
Pathology Research Unit, part of
Plains Agricultural Research Center in College Station.
The research team showed that by coupling what's known as RNA interference
technology, or RNAi, with a seed-specific gene promoter, it's possible to
significantly reduce gossypol levels within cottonseed and not reduce the
levels of gossypol and related compounds in the foliage. The presence of these
compounds in the foliage helps protect the plant from attack by insects.
Gossypol is a toxic pigment that can be safely ingested only by ruminant
animals with complex stomachs, so most of the nutritious meal produced during
cottonseed processing is currently sold as cattle feed.
Use of the RNAi technology to develop new cotton lines could lead to plants
with low enough gossypol levels in the seed that the 44 million metric tons of
cottonseed produced yearly could be used to provide roughly 10 million metric
tons of protein. This would help meet the total protein needs of almost a half
In addition, U.S. consumers craving a new and nutritious snack food could
soon be reaching for crunchy "TAMU nuts," which were developed at
Texas A&M over 20 years ago. Reduced-gossypol cotton seeds have a nutty
flavor and crunch.
The research was published in a recent edition of the Proceedings of the National Academy of
ARS is the U.S. Department of
Agriculture's chief scientific research agency.