Efficient Agrobacterium-mediated transformation and
recovery of transgenic fig (Ficus carica L.) plants
Svetla D. Yancheva
b
, Sara Golubowicz
a
, Zeev Yablowicz
a
, Avi Perl
a
,
Moshe A. Flaishman
a,
*
a
Department of Fruit Tree Sciences, Institute of Horticulture, ARO, The Volcani Center, P.O. Box 6, Bet Dagan 50250, Israel
b
Plant Biotechnology Laboratory, Agricultural University, 12 Mendeleev St., 4000 Plovdiv, Bulgaria
Received 3 October 2004; received in revised form 28 November 2004; accepted 3 December 2004
Available online 27 December 2004
Abstract
An efficient and reproducible system for regeneration and Agrobacterium-mediated transformation of the common fig (Ficus carica L.)
cultivars Brown Turkey (fresh consumption) and Smyrna (dry consumption) was developed. Optimal shoot regeneration (up to 100%) was
obtained on MS basal salt mixture supplemented with 100 mg l
À1
myo-inositol, 1 mg l
À1
thiamine HCl and addition of 2.0 mg l
À1
thidiazuron
(TDZ), 2 mg l
À1
indole-3-butyric acid (IBA), 4% sucrose and 0.8% agar. Regeneration was highly dependent on the dorsoventral orientation
of the explants. When explants were cultured with the adaxial surface up, 100% regeneration was achieved with more than five shoots per
regenerating explant in both studied cultivars. In contrast, if leaves were placed with their abaxial side up, shoot regeneration took place, but
still mostly from the adaxial surface. Leaf explants of in vitro propagated plants were co-cultivated with the disarmed Agrobacterium strain
EHA105 harboring the plasmid pME504 that carried the uidA-intron and nptII genes. Transformation efficiencies were in a range of 1.7–
10.0% for cv. Brown Turkey and 2.8–7.8% for Smyrna. The transgenic nature of the regenerated plants was confirmed by molecular analyses
(PCR and Southern blot) as well as by GUS staining. Similar to regeneration, the orientation of the leaf surface during organogenesis was a
key factor for successful transformation. Successful transformation of commercial fig cultivars provides a new promising tool for the
introduction of foreign genes into transgenic fig cultivars. The regeneration and transformation methodologies described here may pave the
way for transgenic varieties with improved agronomic characteristics, such as storability and disease resistance, and will provide a means for
the production of foreign proteins in the edible parts of fig, leading to improved nutritional and/or pharmaceutical composition.
# 2004 Elsevier Ireland Ltd. All rights reserved.
Keywords: Fig (Ficus carica); Transformation; Regeneration; GUS; nptII; Agrobacterium tumefaciens
1. Introduction
Fig trees are one of the earliest fruit-bearing trees
cultivated. Ficus carica (Moraceae), the well-known fig of
commerce, is indigenous to wide areas ranging from Asiatic
Turkey to North India, and natural varieties are cultivated in
most Mediterranean countries [1]. Fig fruit is well known for
its nutritive value, and is consumed fresh or dry worldwide.
Fig fruits are also known for their mild laxative activity and
high alkalinity, and substances derived from them are used in
various drug preparations. Other parts of fig trees have also
been shown to have a commercial value [2].
Traditional breeding methods of F. carica require a long-
term effort for improving traits such as production of
parthenocarpic varieties. Among F. carica there are trees
that bear only female figs and others trees, named caprifig,
bear both male and female flowers. Edible fruits can be
produced only on trees bearing female synconia, provided
cross-pollination is mediated by a specific wasp [3]. Thus,
traits originated via pollen are hard to track.
www.elsevier.com/locate/plantsci
Plant Science 168 (2005) 1433–1441
Abbreviations: BA, 6-benzylaminopurine; CaMV, cauliflower mosaic
virus; GA
3
, gibberellic acid A3; GUS, b-glucuronidase; IBA, indole-3-
butyric acid; NAA, a-naphthalene acetic acid; nptII, neomycin phospho-
transferase II; PCR, polymerase chain reaction; TDZ, thidiazuron (N-
phenyl-N
0
-1,2,3-thiadiazol-5-yl urea); uidA, b-glucuronidase gene of
Escherichia coli
* Corresponding author. Tel.: +972 3 968 3394; fax: +972 3 966 9583.
E-mail address: vhmoshea@agri.gov.il (M.A. Flaishman).
0168-9452/$ – see front matter # 2004 Elsevier Ireland Ltd. All rights reserved.
doi:10.1016/j.plantsci.2004.12.007
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