| Summary: | Commercial development of new flowering potted plants is stimulated by
overproduction of major crops worldwide and consumer demand for new products. The
process of product development was critically examined and the role of modern plant biology
research in the development process was investigated using new, non-commercial plant genera
for case studies in seed biology and postproduction longevity.
This examination included a review of the history of ornamental plant cultivation and
the scientific literature, and observation of projects in a major, international floriculture
production centre. Development work was most often undertaken by private, international
breeders and propagators of new crop cultivars. Some private producers conducted their own
breeding programs and successfully introduced new products. Product development
consultants and discipline-oriented scientists had a significant role in development work.
Crucial components of the process included identification of a plant species with potential in
floriculture, active involvement of flower producers, confidentiality and product promotion.
One case study investigated the mechanism of seed dormancy, and seed treatments
were tested to improve germination of Lewisia tweedyi and Lewisia cotyledon. These two
lewisia species were found to have dramatically different percent:; and rates of germination
under axenic conditions and in laboratory experiments. Decoating increased germination from
0 to 87% in L. tweedyi which suggests that the seed coat imposes dormancy in this species.
The role of the coat in seed dormancy was supported by measurements of seed coats in
transverse section under a scanning electron microscope. The L. t\v eedyi seed coat was found
to be 22% thicker than the L. cotyledon coat. Scarification of seeds with liquid nitrogen,
infusing gibberellic acid, and an 8 or 12-week stratification improved germination in both species.
Another case study determined the display life of potted plants of Dicentra eximia,
Dicentra formosa, and Dicentra spectabilis. More flowers opensd in a simulated interior
environment room if the plants were treated before harvest with an anionic silver thiosulfate
complex. This increase in flower number resulted in a 75% increase in the display life of D.
eximia (to 14 days) and a 65% increase in the display life of D. formosa (to 28 days). A
similar effect was achieved by producing the plants under supplemental irradiance which also
increased plant height and decreased production time. Height of D. spectabilis could be
controlled by the application of daminozide which had no effect on forcing time, flower
number or display life of the plants.
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