Propagation of Asparagus through Shoot Apex Culture II. Light and Temperature Requirements, Transplantability of Plants, and Cyto-Histological Characteristics1

Bulblets from bulb-scale explants of Lilium longiflorum Thunb. cvs. Ace and Nellie White cultured in darkness on a semisolid Linsmaier-Skoog medium supplemented with 0.03 mg/liter α-naphthalene-acetic acid (NAA) bore no leaves when produced in vitro at constant 30°C but often did when produced at constant 25°. In vitro temperature regimes involving both 25 and 30° resulted in the largest number of leaves per explant. Time in vitro in each temperature regime was calculated to provide equal heat units so that differences could not be explained by a linear relationship between development and temperature × time. Physiological state of explants, measured by time lily bulbs were stored at 4° before tissue culture, interacted with in vitro temperature. Explants from bulbs stored 110 days or less produced significantly fewer but significantly larger bulblets at constant 25° as compared to constant 30°. This difference was not apparent when explants were taken from bulbs stored at 4° more than 110 days. In an experiment with explants from bulbs stored 80 days, there was no significant difference between ‘Ace’ and ‘Nellie White’ in number of scales per bulblet at either 25 or 30° but bulblets of both cultivars contained significantly fewer scales if generated at 30°. Mean width of meristems in ‘Ace’ bulblets was significantly greater when produced in vitro at 30°. Neither initiation of bulblets nor bulblet development appeared controlled by apical dominance.

mentioning

confidence: 99%

Developmental Responses of Lilium longiflorum Bulblets to Constant or Alternating Temperatures in Vitro1

Stimart

Ascher

1981

“…Plantlets develop into plants like the parent, both initially and after repeated subculturing. 6. Rates of production are comparable to or better than rates for conventional propagation.…”

mentioning

confidence: 98%

Propagation of Chrysanthemum in vitro: II. Production, Growth, and Flowering of Plantlets from Tissue Cultures1

Earle

Langhans

1974

Large numbers of normal chrysanthemum plants were produced from tissue cultures derived from 0.5 mm high shoot-tips. The cultures, which consisted of callus with superficial meristems, doubled in weight every 3 days in liquid Murashige-Skoog medium containing 2.0 mg/1 kinetin and 0.02 mg/1 NAA. Cultures resumed growth after at least 6 months storage at 4.5°C. Plantlets formed within 6-12 weeks when small pieces of tissue were transferred to agar media containing 0.5-2.0 mg/1 kinetin. Addition of GA3 (10 mg/1) promoted formation and elongation of leaves and shoots on the tissue. Ability to form plantlets was retained after repeated subculture; a culture started in April 1970 is still producing plantlets. One thousand plantlets were potted and grown in the greenhouse. Small (<1 cm high) plantlets initially grew more slowly than larger ones but almost all plants produced normal white flowers after 2 months short day treatment. This system could produce up to 9 × 1014 plantlets or 90 billion 15 cm plants within a year, a great increase over the number possible via conventional propagation.

“…This appli cation of tissue culture techniques is termed "micropropaga tion" to differentiate it from more conventional means of vegetative propagation (13,25). Shoot tip culture, a form of micropropagation, has been used successfully to produce pathogen-free plants (12), and is now being used in clonal mul tiplication (2,3,4,7,8,9,15,17,18,22,26,28).…”

mentioning

confidence: 99%

Clonal Multiplication of Carnation by Micropropagation1

Davis

Baker

Hanan

1977

Clonal multiplication of carnation (Dianthus caryophyllus L.) was accomplished in three stages: 1) shoot tip culture initiation stage, 2) shoot multiplication stage, and 3) rooting stage. The culture medium for the initiation stage was examined by comparing various inorganic salt mixtures, vitamin mixtures, carbohydrates, growth regulators, agars, pH’s, and additional supplements for their effect on growth and development of multiple shoots from shoot tips. When shoot tips (ca. 1 mm high) were grown on a modified Murashige and Skoog medium with 10 µM kinetin and 1 µM NAA, apical dominance was counteracted and morphologically normal shoots proliferated rapidly. Transferring these cultures after 4 wk to 100 ml flasks (one per flask) with 50 ml of same medium without agar and supplements, and with the kinetin concentration reduced to 2.5 µM, resulted in an average per original shoot tip of 28 shoots over 2 cm in height being produced in another 3 weeks. These shoots were rooted in BR-8 blocks or Jiffy-7 peat pellets under intermittent mist. Plantlets rooted in these supports were transferred easily to greenhouse conditions. Incorporation of carnation micropropagation into a pathogen-free propagative stock program should not be difficult, and might prove beneficial even if large scale use is limited by economic considerations.