Open Collections

Research and development of herbaceous perennials as new potted plants for commercial floriculture : case studies with lewisia seed biology and dicentra postproduction performance

University of British Columbia

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.

Thesis/Dissertation

application/pdf

2009-02-10

For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.

http://hdl.handle.net/2429/4396

Plant Science

University of British Columbia

UBCV

DSpace