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Janet E. A. Seabrook Bruce G. Cumming 《In vitro cellular & developmental biology. Plant》1977,13(12):831-836
Summary A new, rapid technique for the propagation of amaryllis (Hippeastrum spp. hybrids) by means of tissue culture is reported. Leaf bases, scapes, peduncles, inner bulb scales and ovaries were cultured
successfully in vitro and plantlets were induced readily at various concentrations of growth regulators. Some plantlets also
were produced in the absence of growth regulators. The most productive tissues for propagation were inverted scapes and peduncles,
cultured in a modified Murashige and Skoog salt solution with added organic constituents and 1 mg per 1 (4.5μM) 2,4-dichlorophenoxyacetic
acid (2,4-D) and 1 mg per 1 (4.4μM) 6-benzylaminopurine (BAP). Plantlets induced axenically also grew roots on the generalized
shoot-inducing medium so that no special rooting medium was required. Although friable callus was obtained from ovary tissue
cultured on a medium containing 2 mg per 1 (11μM) naphthaleneacetic acid and 4 mg per 1 (18μM) BAP, it produced shoots after
8 weeks of further subculture on the same medium. An average of 10 rooted plantlets was obtained from each scape or peduncle
explant on the shoot-propagating medium. Thus, if 45 explants are obtained from each bulb, 450 rudimentary plantlets could
be obtained from each mother bulb in 8 weeks of culture. This is a substantial increase over present propagation methods.
This work was supported by a grant-in-aid of research, to Bruce G. Cumming, from the National Research Council of Canada. 相似文献
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Corallivorous gastropods of the genus Drupella have caused considerable damage to corals at widely separated reefs in the Indo-Pacific. Morphological variability of Drupella species within and between areas has caused taxonomic confusion. To clarify the relationships, we examined allozyme variation at 16 gene loci in samples from Western Australia, Queensland and Japan. Within sites, the species D. cornus, D. rugosa and D. fragum were distinguishable individually by each of 9 to 11 loci, with average genetic identities of about 0.25. The differences extended across sites, whereas the conspecific genetic identities over distances up to 6000 km were 0.86 to 1.00, supporting the view that there are three widespread species of Drupella. Nevertheless, there is much variation within species for allozymes, size, shape and colour. 相似文献