Page 28 - ARUBA TODAY

A28 SCIENCE
Friday 21 September 2018
Deadly plant disease threatens $250M rose business

By JANET McCONNAUGHEY said Dr. Raj Singh, an LSU
NEW ORLEANS (AP) — The AgCenter plant patholo-
outlook for American- gist.
grown roses is becoming a The center's 40 acres (16.2
bit less rosy, with the spread hectares) with rose gar-
of an incurable virus that's dens are free of the disease
causing major damage to so far, said the society's
the nation's $250-million-a- executive director, Laura
year rose business. Seabaugh.
U.S. rose bush producers Unless an infected bush
account for the bulk of that is removed, experts say,
business and face a grow- mites will spread the virus
ing challenge from rose throughout a garden and
rosette disease, which can beyond.
kill roses within three years. That can mean hard choic-
Its many symptoms include es, said Dr. Mark T. Wind-
super-thorny stems and ham, who's testing plants at
clusters of stems called ro- the University of Tennessee-
settes or witches' brooms. Knoxville to find resistant
One producer spent $1 varieties.
million getting rid of rose "I've had people tell me,
rosette disease and some 'The bush that has it, it's the
smaller nurseries have had only surviving clone of my
to destroy 10,000 plants, great-grandmother's rose.'
said Dr. David Byrne of Tex- I hate to say it, but are you
as A&M University, leader going to try to save that
of a $4.6 million multistate rose and put your 500-bush
project to study the virus rose garden in jeopardy?"
and the mite that spreads he said. The Fort Worth Bo-
it, and to find resistant rose tanic Garden uprooted
varieties. about 2,000 bushes in 2015,
"It moves real easily and it's rosarian Jeffrey Myers said.
hard to detect initially. ... He said their close-set rows
That's really scary for some- let mites "crawl through
one in production," Byrne like a highway from rose to
said. "If it gets in their pots rose." The botanic garden
in their production areas, now has about 350 rose
they've got to eliminate bushes, set at least 3 to 4
thousands of plants. Even feet (1 to 1.3 meters) apart,
then they don't know if with other plants in be-
they've got rid of it." tween as mite roadblocks.
He also said, "I think we're Byrne says some large land-
seeing it in more areas now scapers are not using roses
than 10 years ago." because it's too expensive
The virus, spread by wind- to maintain them.
blown mites about half the Customers still want them
length of a grain of salt, but won't pay to replace
has been found in at least infected plants, said Joe
30 states . In Texas, the Fort Ketterer, with Ruppert
Worth Botanic Garden had A rose bush with the telltale signs of rose rosette virus is pictured at Oklahoma State University's Landscape of Laytonsville,
Plant Disease and Insect Diagnostic Laboratory research plot in Perkins, Okla., Tuesday, Sept. 11,
to replace its entire rose col- 2018. Signs include super-thorny stems and clusters of stems called rosettes or "witches' brooms." Maryland, which works in
lection. The virus recently Associated Press six states and the District of
was found to have spread Columbia. He said his com-
in northwest Louisiana, in- known since the early 1940s Mountains and Manitoba, This virus threatens the rose pany uses roses but prunes
cluding the home city of — and was once hailed as Canada. In the 1990s and bush business, valued at out affected branches, us-
the American Rose Society a possible way to eradi- even the early 2000s, scien- more than $200 million in ing hormones to stimulate
and its gardens — the larg- cate an invasive plant . tists considered it a possible 2015. It appears to be a growth in parts of the same
est U.S. park devoted to the The disease was first identi- way to control those inva- growing issue as more and plant without symptoms.
national flower. fied on wild multiflora roses sive plants. more cultivated roses are At Tennessee-Knoxville, the
Rose rosette has been in California, the Rocky It became recognized as a used in landscapes, ac- University of Delaware and
problem for cultivated ros- cording to a website cre- Oklahoma State, research-
es only in the last decade ated by a coalition of rose ers lodge infected, mite-
or so, Byrne said. producers and scientists. infested twigs in the foliage
It's the latest blow to the In Louisiana, where rose ro- of healthy plants to see
business. South American sette disease was first de- which stay well.
competition forced most tected in 2015, it's spread- "So far we have 20 roses
U.S. growers out of the cut ing at an alarming rate in that look good. This is their
flower market over the past commercial and residen- fourth year," Windham said.
several decades. That mar- tial plantings in Bossier City But their test won't be over
ket has withered from $200 and in Shreveport, where until they've lasted a full
million in 1990 to $22 million the rose society's American four years without infection,
in 2015. Rose Center is located, he said.q