Enhanced bud regeneration in aspen (Populus tremula L.) roots cultured in liquid media |
| |
| Authors: | B Vinocur T Carmi A Altman M Ziv |
| |
| Institution: | (1) Kennedy-Leigh Center for Horticultural Research, Otto Warburg Center for Agricultural Biotechnology, Hebrew University of Jerusalem, P.O Box 12, Rehovot 76100, Israel, IL;(2) Department of Agricultural Botany, Otto Warburg Center for Agricultural Biotechnology, Hebrew University of Jerusalem, P.O Box 12, Rehovot 76100, Israel e-mail: meira@agri.huji.ac.il Fax: +972-8-9467763, IL |
| |
| Abstract: | The regeneration potential of excised aspen (Populus tremula L.) roots cultivated in liquid medium, as affected by plant growth regulators and by the position of the isolated root explant
on the main root, was investigated. The effect of various levels of benzyladenine (BA) and thidiazuron (TDZ) on bud regeneration
in root explants was studied. TDZ in the medium had a marked effect on bud development as compared with BA, inducing a tenfold
increase in the number of buds regenerated from various root explants. TDZ enhanced both root and root-borne shoot biomass
production but reduced further shoot development and elongation. The position of the isolated root sections on the main root
affected regeneration, the proximal sections further away from the root tip producing the highest number of buds per explant
in both BA and TDZ treatments. Buds regenerated in close proximity to the site of lateral roots in BA-treated roots, while
in TDZ-treated root sections, the buds formed all over the root regardless of the presence of lateral roots. The buds developed
from inner cortical and sub-epidermal cell layers, disrupting the epidermis and the inner layers. Root biomass production
and growth was greatly enhanced in well-aerated bioreactor culture in the presence of 4.5×10–2 μM TDZ. A high number of the root-borne shoots could be rooted and converted to plantlets. However, while shoots regenerated
in a medium with BA rooted well in a growth regulator-free medium, shoots formed in a medium with TDZ required auxin for rooting.
Roots cultured in the presence of ancymidol, a gibberellin biosynthesis inhibitor, regenerated non-hyperhydric bud clusters
and hyperhydric shoots. These were separated mechanically, subcultured to growth and rooting medium and transplanted ex vitro
resulting in phenotypically true-to-type plantlets. The potential of liquid cultures for aspen shoot biomass production from
roots is discussed.
Received: 24 January 2000 / Revision received: 6 March 2000 / Accepted: 7 March 2000 |
| |
| Keywords: | Populus tremula Liquid culture Root explants Thidiazuron |
| 本文献已被 SpringerLink 等数据库收录！ |
|
