Effects of ethylene on somatic embryogenesis and galanthamine content in Leucojum aestivum L. cultures

Abstract

The influence of ethylene on in vitro morphogenesis of Leucojum aestivum and galanthamine accumulation was studied. Calli were cultivated on Murashige and Skoog (MS) medium supplemented with 25 lM 4-amino-3,5,6-trichloropicolinic acid (picloram) and 0.5 lM benzyladenine (BA). During incubation under these conditions, callus cultures produced ethylene (9.5 nL/g fresh weight: F.W.) whereas no ethylene was found in somatic embryos cultivated on medium supplemented with 0.5 lM a-naphthalene acetic acid (NAA) and 5 lM zeatin. Application of the precursor of ethylene 1-aminocyclopropane-1-carboxylic acid (ACC) increased ethylene production in both cultures, and decreased callus growth by a factor of 1.2, whereas callus growth was enhanced by a factor of 1.1 in the presence of an inhibitor of ethylene silver nitrate (AgNO 3 ) or by a factor of 1.2 with an absorbent potassium permanganate (KMnO 4 ). ACC enhanced the induction of somatic embryos and the development of globular embryos. Removal of ethylene by KMnO 4 during somatic embryogenesis led to the development of plants with greater length. Silver thiosulphate (STS) induced galanthamine production in callus cultures (0.1% dry weight), whereas ACC induced galanthamine production in somatic embryo cultures (2% dry weight).

Influence of auxins on somatic embryogenesis and alkaloid accumulation in Leucojum aestivum callus

“…150 mg of powder were macerated in methanol (10 mL) for 24 hours, with sonication for 90 minutes in an ultrasonic bath (Transsonic 460/H Elma) at room temperature as performed by Ptak et al [12]. After centrifugation at 2540xg for 20 minutes, crude methanolic extracts were passed through Upti-clean SPE columns SCX 100 mg/3 mL from Interchim.…”

“…The low Amaryllidaceae alkaloid accumulation commonly observed in in vitro cultures of Leucojum aestivum [6,[9][10][11][12][13] was probably due to the fact that the level of the alkaloid biosynthesis is strongly influenced by cellular differentiation [10,[14][15][16]. In particular, enhanced synthesis of galanthamine accompanied development of somatic embryos [17].…”

“…In particular, enhanced synthesis of galanthamine accompanied development of somatic embryos [17]. Somatic embryogenesis may be influenced by many factors [18], including ethylene production [12] and growth regulators like auxins. Embryogenic callus is usually formed in auxin-supplemented media, and the most commonly used auxin for this purpose is 2,4-D [19].…”

Production and antioxidant capacity of tissue cultures from four Amaryllidaceae species

“…Several tissue cultures of Amaryllidaceae involve the growth regulators NAA, IAA as auxins and BA as a cytokinin [7,10,27,28]. Auxin/cytokinin combinations involving growth regulators mentioned are potent inducers of embryogenic callus formation and/or mass plant propagation in this family.…”

Leucojum aestivum L. in vitro bulbs induction and acclimatization

“…Micropropagation ensures rapid multiplication of selected genotypes, allowing the useful metabolites to be collected in greater quantities. Several studies on Leucojum aestivum multiplication by organogenesis and somatic embryogenesis have been performed [5,8,9]. Species that naturally produce bulbs, like Leucojum aestivum can be induced to form bulbs in in vitro culture.…”