Ralstonia To-Date

January 30, 2004 - 13:06

Since
the Ralstonia announcement was made about a month ago, there has been so much
information floating around about the outbreak that no one really knows what is
going on with the disease at this point. Well, we have figured out some of it
and are here to tell you the latest information that is going on to date. We
have spoken to Lin Schamle from SAF, Dore Mobley from APHIS and Richard
Goldsmith who consulted with his production manager Don Snow about the
following information, and everyone seems convinced that the following is true
at this time. While the main structure of the following events might already be
common knowledge, many of the specifics are just now coming to light.

According
to a document from APHIS, the Plant Protection and Quarantine (PPQ) Center for
Plant Health Science and Technology laboratory in Beltsville, Md., confirmed
the presence of Ralstonia solanacearum
TimesNewRomanPS;color:black'>race 3 biovar 2 in geraniums from one commercial
greenhouse in New York State, in rooted cuttings of 'Americana Coral' on
December 31, 2003 and in direct-ship material of 'Americana Bright Red' on
January 2, 2004. The greenhouse had received both varieties of infected
propagative material from the Goldsmith Plants, Inc. facilities located in
Guatemala. The rooted plants (Americana Coral) were received via Glass Corners
Greenhouse in Michigan. The third suspect variety, 'Americana Cherry Rose II',
was implicated and held because it was grown in the same greenhouse with the
two other suspect varieties.

Based
on the positive findings, Goldsmith Plants, Inc. had voluntarily quarantined
its Guatemalan greenhouses, and suspended shipments of geranium cuttings. On
January 6, 2004, APHIS notified Goldsmith Plants that further importations of
geranium cuttings from the suspect Guatemala facility would be prohibited until
further notice.

During
the week of January 5, the PPQ and its state partners began issuing emergency
action notices to potentially affected facilities, based on a list that
Goldsmith Plants provided, and initiated an eradication program. Eradication
efforts began with the four rooting stations: Glass Corner Greenhouse, Grand
Rapids, Mich.; Rakers Acres, Litchfield, Mich.; Speedling, Blairsville, Ga; and
Pacific Growers, Blaine, Wash. It is estimated that 400,000 plants were
destroyed between the four rooting stations.

During
the week of January 12, the PPQ continued to hold potentially infected plants but
put a temporary moratorium on their destruction pending the results of a site
visit to the suspect production facility in Guatemala. In Guatemala, scientists
found wilted plants among two of the three suspect varieties at several
locations in one greenhouse. They confirmed the presence of Ralstonia sp. (not Ralstonia
solanacearum
race
3 biovar 2) in samples from these plants with two different serologically based
tests. Confirmation of Ralstonia in the Guatemalan samples to the target race
and biovar was later received on January 23, 2004, confirming that an Americana
Bright Red did in fact have Ralstonia solanacearum
style='font-family:TimesNewRomanPS;color:black'>race 3 biovar 2.

Based
on the findings in Guatemala, PPQ reinstated the destruction order for the
three suspect varieties and other potentially exposed plants that were shipped
from Guatemala between July 27, 2003 and January 3, 2004. As of January 26,
2004, APHIS estimates that 459 facilities in 41 states have received suspect
geraniums; 362 facilities are on hold, 79 control actions have been initiated,
68 facilities have been released, and 529, 367 plants have been destroyed.
Current estimates are that between 1.5 and 2 million cuttings/plants will be
destroyed.

Richard
Goldsmith said that APHIS is meeting early this week to discuss the next steps
and additional test results if they become final. He says that if all goes
well, AHPIS may be ready to allow the Goldsmith Plants' Guatemalan facility to
commence with production as soon as later this week.

USDA
is diligently working, with Goldsmith's cooperation, to develop a water
effluent (waste water) testing system to quickly and accurately determine the
presence or absence of R. solanacearum
TimesNewRomanPS;color:black'> in a greenhouse. This system may be available for
use in offshore geranium production facilities in the near future, but it will
require further testing and development before it can be used in U.S.
greenhouses because of different soils/media and watering systems.

According
to Lin Schmale, "Beyond the obvious significance, this test is important
because the research was funded through the Floriculture and Nursery Research
Initiative, from USDA-ARS (Agricultural Research Service) dollars. The
Initiative is an effort that SAF and the American and Nursery and Landscape
Association have worked on for many years, and the industry has lobbied
Congress for dollars to go towards efforts that will benefit the floral and
nursery industry. Because of our close working relationship with ARS, we were
able to put some of the Initiative money, last year, into a research project by
Dr. Caitilyn Allen, University of Wisconsin, which almost immediately came up
with several answers to previously unanswered scientific questions -- and has
led to this water effluent testing protocol.

Growing
practices are very important in a situation like this, commercial growers in
the U.S. need to help protect themselves in the event of any disease
introduction -- but particularly Ralstonia, One thing to remember is that any
grower who has Federal Crop Insurance may be covered on this issue (it depends
on the state and the particular policy) but that you must contact your agent
before destruction occurs. Here is a list of sanitation practices that would be
beneficial towards keeping your greenhouse disease free:

  • style='font-family:TimesNewRomanPS'>Do not use sub-irrigation or shared
    watering systems;
  • style='font-family:TimesNewRomanPS'>Use strict sanitary practices when
    handling or propagating plants;
  • style='font-family:TimesNewRomanPS'>Maintain varieties of geraniums from
    foreign sources separately;
  • style='font-family:TimesNewRomanPS'>Do not hang baskets of geraniums over
    other crops;
  • style='font-family:TimesNewRomanPS'>Do not grow geraniums on the ground or
    on the kind of plastic sheeting or other surface that would allow water to
    spread from one pot to another;
  • style='font-family:TimesNewRomanPS'>Disinfect water systems and regularly
    treat irrigation water from any source; and
  • style='font-family:TimesNewRomanPS'>Keep greenhouses, areas around
    greenhouses and irrigation water holding or overflow ponds free of weeds.

This
information came from the APHIS Action Guide
TimesNewRomanPS;color:blue'>http://www.aphis.usda.gov/ppq/ep/ralstonia/rasltoniaactionplanv4web.pdf

SAF and ANLA also
have a "Quick Guide" that is an
informational and precautionary piece for growers about Ralstonia. For a more
in-depth look go to www.safnow.org or www.anla.org.

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