Brazilian Designer Genes May Make Hotter U.S. PetuniasBy
Jill Lee April
30, 1998
Imagine a greenhouse with perfume-scented petunias--fire-red flowers
hot enough to raise a blush, giant 4-foot-high petunias with
Pegasus-white blooms. But this greenhouse is no dream: Its the
real-life setting for work by a top U.S. plant breeder, a Brazilian
taxonomist and a plant geneticist at USDAs
Agricultural Research
Service.
ARS researchers with the U.S. National Arboretums
Floral
and Nursery Plants Research Unit are using the latest techniques
in chemical and genetic biology to cross wild Brazilian flowers with
American standard varieties. They get the germplasm from breeder Fred
Meyer, who traveled with cooperator Joao Stehmann to Brazils
mountains for cold-tolerant flowers growing in the snow. The giant
shrub with big milky blossoms came from Ecuador.
Meyer and Stehmann also found a new drought-tolerant, smooth-leaved
petunia species gracing the beaches of the Torres Coast. Its traits
offer alternatives to American petunias strong scent and low
drought tolerance.
ARS researchers working at the floral and nursery research facility
know how to solve special breeding problems. They use genetic analysis
to differentiate potential petunia bloodlines and pick
parent plants to create amazing colorful petunias that will someday
wow American consumers.
American petunias dont make great hanging baskets because
their hairy leaves and stems turn a decorators delight into a
household annoyance by clinging to clothes, hair and everything else.
But the South American plants arent perfect. Brazilian petunias
mostly come cloaked with majestic purple blooms. Hybrids need to be
created in a variety of colors. The ground-covering coastal petunias
spread 4 to 5 feet, but lack the blossoms of U.S. lines. Making
Brazilian-U.S. crosses could give consumers the best of both worlds.
Traditional plant breeding fails, as genes for the unwanted
traits--like hairiness--reside right next to desirable ones. And
first-cross, Brazilian-American offspring can look identical, but only
some have the winning genetic combination. This is where ARS
techniques break the breeding barrier.
Scientific contact: Robert J. Griesbach, ARS
Floral
and Nursery Plants Research Unit,
U.S.
National Arboretum, Beltsville, Md., phone (301) 504-6574, fax
(301) 504-5096, rgriesbach@asrr.arsusda.gov.
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