Azalea Flower Research Articles

Two new yeast species belonging to the genus Candida.

Four new yeasts, Candida glucosophila from brown sugar, Candida dulciaminis from confectionery, Candida floricola from dandelion and azalea flowers, and Candida vaccinii from blueberry flowers are described on the basis of morphological, physiological, and biochemical characteristics. C. dulciaminis is considered to be a basidiomycetous yeast.

Supercooling in Overwintering Azalea Flower Buds

Differential thermal analysis and nuclear magnetic resonance spectroscopy experiments on whole flower buds and excised floral primordia of azalea (Rhododendron kosterianum, Schneid.) proved that supercooling is the mode of freezing resistance (avoidance) of azalea flower primordia. Increase in the linewidth of nuclear magnetic resonance spectra for water upon thawing supports the view that injury to the primordia occurs at the moment of freezing. Nonliving primordia freeze at the same temperatures as living primordia, indicating that morphological features of primordial tissues are a key factor in freezing avoidance of dormant azalea flower primordia. Differential thermal analyses was used to study the relationship of cooling rate to the freezing points of floral primordia in whole flower buds. At a cooling rate of 8.5 C per hour, primordia in whole buds froze at about the same subfreezing temperatures as did excised primordia cooled at 37 C per hour. At more rapid cooling rates primordia in intact buds froze at higher temperatures.

Azalea Flower Bud Development and Dormancy as Influenced by Temperature and Gibberellic Acid1

Abstract Flower bud development was ascertained by biweekly dissections of shoot apices, until bud color was apparent. Satisfactory results were obtained when plants were given 3 weeks at 2 or 9°C, followed by 3 applications of GA3 at 250 ppm. The results were less satisfactory when attempts were made to completely substitute GA3 for the cool temp requirement to break dormancy.

The respiration and flower development of evergreen azaleas as influenced by gibberellin, scale removal, and 2, 4-dinitrophenol

Scale removal had little effect on time of flowering of Erich Schaame azalea flowers whether or not the azalea plants had been sprayed with gibberellic acid (GA3). Apparently the scales acted as a barrier to oxygen diffusion. GA3 treatments induced earlier flowering and an increase in oxygen uptake of the flowers. 2, 4-Dinitrophenol was more effective in stimulating the oxygen uptake of check flowers than in stimulating the oxygen uptake of GA3-treated flowers. DNP retarded the rate of flower development of GA3-treated flowers, but not of check flowers.