
Orange Cauliflower May Help Crop Scientists
Boost NutritionBy Hank Becker July 7, 1999An orange cauliflower plant, found
growing in a Canadian field nearly 30 years ago, could provide important
genetic clues for boosting the nutritional value of many different crops. The
mutant cauliflower produces so much beta-carotene--an orange pigment in carrots
and other fruits and vegetables--that normally white parts of the plant turn
orange. Beta-carotene belongs to a class of compounds known as carotenoids,
important to human nutrition. Plant molecular biologist David F. Garvin at the
Agricultural Research Service is
studying the mutant cauliflower as a model for unraveling the biochemical and
molecular basis of carotenoid production in crops. Chemical analyses indicate
beta-carotene concentrations in some tissues of the mutant are
several-hundred-fold higher than normal cauliflower, according to Garvin at the
U.S. Plant, Soil and Nutrition Laboratory in Ithaca, N.Y. The lab is part of
ARS, USDA's chief research agency. Beta-carotene has antioxidant properties that may reduce the incidence of
cardiovascular disease and certain types of cancer. It's also an important
source of vitamin A. But many crops important to human diets contain little or
no beta-carotene. Garvin hopes the research will ultimately provide information
needed to genetically engineer increased carotenoid content in important crops
like wheat and rice that lack the compounds. Various characteristics of the mutant have led Garvin to postulate that an
altered gene in it may act as an important switch for turning carotenoid
production on or off. The programming error, according to Garvin, is due to an
alteration in one gene. His preliminary molecular studies suggest this gene
alteration may influence other genes required for synthesizing beta-carotene. A
story about the mutant cauliflower appears in the July issue of Agricultural Research magazine
and on the web at: http://www.ars.usda.gov/is/AR/archive/jul99/cauli0799.htm Scientific contact: David F. Garvin, ARS
U.S. Plant, Soil and
Nutrition Laboratory, Ithaca, N.Y., phone (607) 255-7308, fax (607)
255-1132, [email protected]. U.S. Department of Agriculture | |