Search Results
Abstract
Potted ‘Ace’ lily bulbs were treated with 1000 ppm of either gibberellin A3 (GA3) or gibberellins A4+7(GA4+7) as a soil drench using 200 ml per pot on January 6, 1971. GA treatments had no effect on the time of floral initiation, however, GA3 decreased the days to flowering when compared to either GA4+7 or water controls. GA4+7 and GA3 reduced the number of primary flowers initiated. and completely inhibited the initiation of secondary flowers. GA4+7 increased the number of primary flowers which aborted shortly after initiation and GA3 did not. Both GAs increased plant height; GA4+7 had the greater effect. GA4+7 significantly reduced the length of the lower leaves, but none of the treatments affected the number of leaves produced.
Abstract
Nonprecooled and precooled ‘Ace’ lily bulbs were placed in the dark at 5, 9, 13, 17, and 21 °C and basal root growth determined at weekly intervals for 5 weeks. Roots originating from the basal plate were designated as primary roots; those originating from the primary roots were designated as secondary roots. The total fresh wt of secondary roots of nonprecooled and precooled bulbs increased with length of storage and increased temp. Optimum root growth occurred at 21°C. Primary roots of nonprecooled bulbs responded similarly to the secondary roots, while those of precooled bulbs had a temp optimum of 17 to 21°C. It was concluded that for commercial use, both nonprecooled and precooled bulbs should be initially grown at approx 17°C to stimulate basal root growth.
Abstract
Procedures are described for critical point drying the shoot apical meristems of Easter lilies for viewing in the scanning electron microscope. This preparatory technique was superior to either freeze-drying or the use of freshly isolated meristems. Photomicrographs of the morphological development of the entire shoot apex from the vegetative through several reproductive stages are presented. The morphology of a single flower is also illustrated.
Meristem diameter measurements revealed seasonal and bulb source variations. Diameter increased with increasing bulb size. When compared to non-cooled bulbs, low temperature treatments reduced meristem diameter prior to flower initiation. The average date of flower initiation of controlled temperature forced ‘Ace’ lilies over a 5-year period was January 21; whereas precooled lilies initiated about 1 week earlier. Greenhouse temperatures of 17−25°C accelerated the date of flower initiation when compared to 13°. A simplified technique for measuring the meristem diameter and observing the stage of development was developed.
The Easter lily forms 2 classes of primary flowers, initial and raised. They can also form secondary flowers. The number of initial primary flowers was correlated with meristem diameter. Larger bulb sizes resulted in a greater number of raised primary flowers. In general, only large bulbs formed secondary flowers. A greenhouse temperature of 13°C promoted the formation of raised primary flowers, while 21° promoted the formation of secondary flowers.
A measurement of the sprouting index showed seasonal and bulb source differences.
Abstract
Potted ‘Ace’ lily bulbs were treated with gibberellic acid (GA3) as a soil drench using varying concentrations, numbers of applications and at different stages of development. There was no consistent effect on the forcing days to flower, plant height or the number of leaves, however, specific treatments with 1000 ppm significantly reduced the number of floral buds initiated. It appears that the most sensitive stage of application is that period just prior to flower initiation and that the GA3 must be applied at this time in order to reduce the number of floral buds initiated. A preliminary experiment indicated that GA4+7 was more effective than GA3. GA4+7 influenced plant height and leaf length as well as the number of floral buds but had no effect on the forcing days to flower.
Abstract
Tulip bulbs (Tulipa spp.) were placed under ventilated low pressure storage (LPS) conditions for 14 days in either August or September. Compared to 760 mm Hg stored bulbs, LPS suppressed leaf growth and floral development. These effects were highly visible after storage in air at either 76 or 150 mm Hg and in the month of August. When tulip bulbs were forced, LPS treatments applied in August delayed flowering of most cultivars and flower size was occasionally reduced; in September treatments, LPS ventilation with additional O2 and CO2 accelerated flowering of 2 cultivars, but flower size was reduced. When stored under 76 mm Hg in air in August, most cultivars of hyacinth (Hyacinthus spp.) were subsequently delayed in flowering, but daffodils (Narcissus spp.) were not. Except for one cultivar of each species, LPS did not affect the percent of plants flowering, plant height or flower size. Penicillium growth on the bulb tunics was enhanced by humidifying the air under LPS conditions. It is concluded that LPS provides no advantages over the ventilated, temperature controlled units presently employed.