In a message dated 06-Jul-04 6:29:39 PM Pacific Daylight Time,
johnbryan@worldnet.att.net writes:

John ~

Judith Freeman (of Columbia-Platte Lilies and The Lily Garden) has said the
issue is that meristem culture did not remove all the virus particles in the
bulbs multiplied by meristem culture. The remaining few particles were too few
to be detected by ELISA tests. For that reason, it is necessary to
periodically repeat these tests to have any assurance of virus freedom. What, in
effect, is happening with these supposedly virus-free lilies is that the
undetectable virus gradually works itself back up to levels that present the standard
symptomology. I would imagine to get a truly virus free lily, one would have to
continuously to incubate sections of the innermost scales.

I really know daffodils more than I do lilies and it is common for seedlings
to be free of virus. If a given clone is also a prime show flower, it soon
contracts one or more of the daffodil viruses from careless activities by the
grower and usually at the hybridizer/commerical grower level. One prime form of
spreading daffodil virus is the machine-based Dutch method known as
"cutting." A daffodil bulb is sliced into sections (analogous to an orange) by machine
to be incubated to generate bulblets between the scales and then planted out.
While this was a major advance in productivity, it also carries with it the
seeds of its own destruction. The cutting head is changed out between clones
and, often between stocks, but not (obviously) between individual bulbs. The
interesting thing with Narcissus and its virus pathogens is that a given clone
can live for decades in spite of it, blooming and multiplying.

Dave Karnstedt
Cascade Daffodils
Silverton, Oregon, USA
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