Search Results
Abstract
‘Superstar’ bulbs grown at 21°C required cold for inflorescence evocation. The cold requirement was reduced under 18 hour day lengths.
Abstract
The broadest diameter of precooled liles was close to the plant base after a 0.5-0.75 mg/pot ancymidol soil drench at shoot emergence. These plants were short, shaped similar to controlled-temperature-forced plants, and of improved commercial value. Shape was not improved by an ancymidol spray at a later growth stage. Low light levels increased plant size, and the absolute reduction of height by ancymidol was greater in shade than in full light, but the percent height reduction was similar for the 2 irradiances.
Abstract
Northern Europe, the land of the midnight summer sun, is also the land of incredible winter darkness. Nonetheless, some of the world's highest standards of living are found there, and winter life is colored by an abundance of bright flowers and savory fresh vegetables. The greenhouse industry of Northern Europe is awesome for its size, diversity, and sophistication. Ability to efficiently use variable-priced energy (petroleum products and electricity) is a pivotal factor for success in that industry. Fuel costs differ based on consumption rates; winter insolation decreases proportionally with distance from the equator, and the warming influence of ocean currents changes drastically from maritime to continental climate. Grower costs also differ because some countries are either naturally endowed with more energy resources or subsidize energy use. Product quality, industry efficiency, and feasibility of transport also are involved in the ability of individual growers to compete in the national and international markets.
Abstract
The late flowering, tall Salvia cultivars flowered faster, were shorter, and had fewer nodes per plant under a short daylength, while the early flowering, short cultivars responded only slightly to daylength differences. Early and late, short and tall cultivars have perhaps been derived as selections from a pool of variable photoperiodic sensitivities.
Abstract
In daylength-responsive salvia cultivars long photoperiods delayed flowering and increased height. The critical daylength was 15 - 16 hours, and above this, the response was proportional to daylength.
Abstract
Since Derek Smith (23) in 1963 used the term vernalization to describe the cold storage requirement of Easter lilies, the appropriateness of the term periodically has been questioned. Even among those who now accept this terminology, differences of opinion have arisen in interpretation of past and current experimental results. It is with this in mind we wish to clarify our reasons for enthusiastically accepting the vernalization concept for Easter lilies.
Abstract
A single spray application of succinic acid-2, 2-dimethylhydrazide (daminozide) at 2,500-15,000 ppm at pinch was effective in retarding growth of bleeding heart, reducing plant height 33 to 75%. A single spray or drench of (2-chlorethyl) trimethylammgrium chloride (chlormequat) had little retarding influence. Spray application of (2-chloroethyl) phosphonic acid (ethephon) had little effect on plant height, but considerably increased the number of nodes and delayed flowering.
Abstract
The flowering response of ‘St John’s Fire’ salvia is day neutral and occurs between the 8-13th node under both 8 (SD) and 24 hour (LD) photoperiods. In contrast ‘Bonfire’ flowers between the 8–13th node under SD and under LD flowering is delayed to the 16-19th node. Genetic experiments indicate that this difference in photoperiodic response is controlled by a single gene: RR flowers from node 16-20, Rr from node 13-17, and rr from node 8-13. A single dominant gene S conditions stem stripedness; ss is solid colored. S-s and R-r are independently inherited.
Abstract
The juvenile phase for flowering of daylength responsive salvia, ‘Bonfire’ and ‘Red Pillar’, ended at stem node 4–6. Then to 20 short days were required for evocation and initiation of flowering. There was a quantitative short-day requirement for inflorescence development in these cultivars. Inflorescence development of day-neutral salvia, ‘St. John’s Fire’ and ‘Fireball’, was not appreciably affected by photoperiod.
Abstract
Growth and flowering of bleeding heart were promoted by 14 to 24 hour photoperiods or light interruptions in the middle of the night. Cold treatment of crowns promoted growth and flowering at short photoperiods. Light at 9 klx promoted growth and inflorescence formation, but greater intensities were required to achieve anthesis. Growing temperatures of 15-22.5°C were most desirable.