The Tomato Magazine
Twice as Nice Breeding Versatile Vegetables
Can you eat your peppers and have them too?
Yes, you can. At least, thats the opinion of two Agricultural Research
Service geneticists. Since 1991, John Stommel, of the ARS Vegetable Laboratory,
and Robert Griesbach, of the ARS Floral and Nursery Plants Research Unit,
both in Beltsville, Maryland, have bred peppers to please both the eye
and the palate. These peppers have been developed through a cooperative
research and development agreement with PanAmerican Seed Company and McCorkle
The eye-catching Black Pearl, released in 2005 and honored as a 2006 All-America
Selections (AAS) winner, attests to their success in developing new cultivars
with both aesthetic and culinary appeal. The award recognizes new fl ower
and vegetable varieties that demonstrate superior garden performance
in trials conducted throughout the country. Black Pearl is a robust plant,
adaptable to environments from New England to California, Stommel says.
In addition, it resists attacks from many insects and fungi and is remarkably
The pepper is now on display at the U.S. National Arboretum in Washington,
D.C., which is part of ARS. With moderately shiny, black leaves and glossy
fruits that ripen from black to red, Black Pearl offers a temptation few
pepper enthusiasts could resistand the AAS judges arent the
only people who think so. Since its release, more than 2 million seeds
have been sold.
A Peck of Pretty Peppers
Black Pearl has company. Stommel and Griesbach look forward to releasing
several new pepper cultivars in the future, including one with spreading
black foliage and colorful upright peppers with a spicy flavor. Another
is exceptionally tallgrowing as high as 3 feet. A third, which produces
fruit around Halloween, has black foliage and orange, pumpkin-shaped fruit.
Ornamental peppers are just one part of a growing industry. Nursery,
landscape, and floral plants are big business, worth about $16 billion
a year in this country alone, according to USDAs Economic Research
Breeding these culinary ornamental peppers has been a cross-laboratory
effort. How did the breeders do it? The fi rst step is to isolate individual
traits and select the ones they want, Stommel says. Within the Capsicum
genus, there is great variety among qualitieslike the size, shape,
and color of leaves and fruits.
Griesbach compares the process of pepper breeding to assembling a Mr.
Potato Head doll. By selecting specifi c characteristics, breeders can
make desirable combinations. Any new combination will
create a novel pepper.
Only your imagination is limiting, he says. Breeding a new
cultivar takes 10 to 15 years and involves making crosses and submitting
the resulting plants to rigorous tests. But creating tasty and attractive
plants isnt the only benefi t of the ornamental pepper breeding
program. This work also has applications for many plant genetics studies.
Pigments Impart More Than Color
These peppers arent the fi rst plants to come out of the Vegetable
Laboratory with both aesthetic and culinary appeal. Earlier research produced
tomatoes rich in the carotenoids lycopene and beta-carotene, red and orange
pigments that give tomatoes their characteristic color. Lycopene and beta-carotene
are antioxidants and have been linked to health-promoting benefits, so
increasing tomatoes carotenoid content improves not only their color,
but also their nutritional value.
What health benefi ts do culinary ornamental peppers have? And what can
they teach us about other plants? Griesbach and Stommel are now exploring
the biochemistry of the anthocyanin pigments responsible for the Black
Pearl peppers deep-black color. In addition to providing pigmentation,
anthocyanins in plants have several tasks including protecting them
against strong ultraviolet (UV) sunlight that could damage their cellular
DNA. Anthocyanins are located in the outer layers of plants, where increased
exposure to UV light or ionizing radiation spurs chemical messenger molecules
to speed up anthocyanin production. When consumed, these anthocyanin pigments
function as antioxidants. Griesbach and Stommel have created a system
for nutritionists to effi ciently evaluate humans.
With a better understanding of that metabolic fate, the scientists envision
finding ways to increase the anthocyaninand nutritionalcontent
of other vegetable crops, not just peppers.
We must figure out which anthocyanins are the best phytonutrients,
says Griesbach. Once we know that, we can find and activate the
genes involved in their production and move them into other plants.
Initial results have proven positive. In 2005, in controlled-environment
experiments inside a growth chamber, Griesbach, Stommel, and colleagues
determined environmental conditions for varying anthocyanin production
in Black Pearl. Although the plant can adapt to many environments, its
growing season and anthocyanin production vary with the temperature and
sunlight of its immediate surroundings.
Once the scientific duo gains knowledge of the metabolic pathways at a
molecular levelwhich Griesbach estimates should come sometime in
2006theyll know how to increase the nutritional and anthocyanin
content of different plant tissues.
We plan on eventually creating more of these versatile crops,
says Stommel. These will be plants that, like Black Pearl, not only
look good, but can be eaten. These plants will serve as both ornamental
and food cropsdoubling their value.
When more of the anthocyanin research is complete, ARS nutritionists Janet
Novotny and Beverly Clevidence, of the Beltsville Human Nutrition Research
Center, will be able to evaluate the biological activity of pepper phytonutrients
in humans. This work will be useful for future breeding efforts and could
allow scientists to produce plants with even higher nutrient content.By
Laura McGinnis and Alfredo Flores, Agricultural Research Service Information
This research is part of Plant Genetic Resources, Genomics, and Genetic
Improvement, an ARS National Program (#301) described on the World Wide
Web at www.nps.ars.usda.gov. John Stommel is with the Vegetable Laboratory,
10300 Baltimore Ave., Beltsville, MD 20705-2350; phone (301) 504-5583,
fax (301) 504-5555. Robert J. Griesbach is in the Floral and Nursery Plants
Research Unit, 10300 Baltimore Ave., Beltsville, MD 20705-2350; phone
(301) 504-6574, fax (301) 504-5096. Twice as Nice Breeding Versatile
Vegetables was published in the September 2006 issue of Agricultural
© 2006 Columbia
>> Return to top
Columbia Publishing & Design | 1-800-900-2452