Plant Biotechnology

Electronic Journal of Biotechnology ISSN: 0717-3458 Vol. 12 No. 2, Issue of April 15, 2009
© 2009 by Pontificia Universidad Católica de Valparaíso -- Chile Received November 29, 2007 / Accepted March 14, 2008
DOI: 10.2225/vol12-issue2-fulltext-3
RESEARCH ARTICLE

Preservation of endangered Tunisian grapevine cultivars using embryogenic cultures

Badra Bouamama*
Centre de Biotechnologie de Borj-Cédria
Laboratoire de Physiologie Moléculaire de la Vigne. B.P. 901
Hammam-lif, 2050, Tunisie
Tel: 00 216 79412 938
Fax: 00 216 79412 638
E-mail: Badra_bouamama@yahoo.com

Rahma Jardak
Centre de Biotechnologie de Borj-Cédria
Laboratoire de Physiologie Moléculaire de la Vigne. B.P. 901
Hammam-lif, 2050, Tunisie
Tel: 00 216 79412 938
Fax: 00 216 79412 638

Asma Ben Salem
Centre de Biotechnologie de Borj-Cédria
Laboratoire de Physiologie Moléculaire de la Vigne. B.P. 901
Hammam-lif, 2050, Tunisie
Tel: 00 216 79412 938
Fax: 00 216 79412 638

Abdelwahed Ghorbel
Centre de Biotechnologie de Borj-Cédria
Laboratoire de Physiologie Moléculaire de la Vigne. B.P. 901
Hammam-lif, 2050, Tunisie
Tel: 00 216 79412 938
Fax: 00 216 79412 638

Ahmed Mliki
Centre de Biotechnologie de Borj-Cédria
Laboratoire de Physiologie Moléculaire de la Vigne. B.P. 901
Hammam-lif, 2050, Tunisie
Tel: 00 216 79412 938
Fax: 00 216 79412 638

*Corresponding author

Financial support: High Ministery of Education and Scientific Research and Technology.

Keywords: forced anthers, long-term maintenance, somatic embryos, Vitis vinifera.

Abbreviations:

2,4-D: 2,4-dichlorophenoxyacetic acid
CP: Chée and Pool (1987) basal medium
D: dichlorophenoxyacetic acid
IASP: indole 3 aspartic acid
MS: Murashige and Skoog
TDZ: thidiazuron

Abstract   Full Text

The preservation of embryogenic lines derived from several endangered local grapevine cultivars was studied. Embryogenic calluses were obtained from immature anthers of eight cultivars, sampled on both fruity-cuttings and field grown vines. Anthers at the ‘separated flower’ stage, derived from fruity-cuttings, resulted in an increased induction of somatic embryogenesis, compared to those derived from the field. Pro-embryogenic calluses were induced on Chée and Pool (1987) basal medium, supplemented with 9 µM of 2,4-dichlorophenoxyacetic acid (2,4-D) and 11.35 µM of thidiazuron (TDZ) under dark conditions. Different anther zones (filament, abaxial, adaxial, lateral zones and entire anthers) were involved in somatic embryogenesis induction. The percentages of granular and yellowish pro-embryogenic calluses ranged between 15.6% and 34.8% in ‘Kahli Kerkennah’ and ‘Muscat Raf-raf’ cultivars, respectively. Although, morphological diversifications of pro-embryogenic calluses (several necrosis and spontaneous maturation) were observed on the induction mediumafter 5 subcultures. The reduction of 2,4-D and TDZ levels to 4.52 µM and 2.89 µM respectively, induced granular and yellowish embryogenic material. Thus, Chée and Pool (1987) (CP) enriched with 4.52 µM of 2,4-D and 2.89 µM of TDZ revealed to be the most appropriate for long-term maintenance. In fact, all the cultivars presented high and regular embryo maturation rates after 12, 24, 36 and 48 months of cultivation on this medium, under light conditions. After 4 years, they still exhibit high germination and regeneration abilities. Germination of somatic embryos was achieved on Murashige and Skoog (1962) basal-medium, with rates ranging from 69% to 96%. Only 5% of somatic embryos were concerned by morphological variations. The regenerated plantlets presented a normal phenotype under controlled greenhouse conditions, compared to mother plants.

Supported by UNESCO / MIRCEN network