Callus initiation and growth and plantlet regeneration were studied using eight cultivars of Raphanus sativus L., including six Japanese radishes, one Chinese and one small `Comet' radish. The basal medium was composed of Murashige and Skoog inorganic salts, 2.0 mg myo-inositol/liter, 0.5 mg each of nicotinic acid and pyridoxine·HCl/liter, and 0.1 mg thiamine·HCl/liter, 30 g sucrose and 2 g Gelrite/liter. High callus yields were obtained on basal medium containing (mg·liter-1) 0.1 2,4-D and 1.0 BA for two Japanese radishes and 0.1 NAA and 1.0 kinetin for `Comet' radish. Shoots were regenerated from callus by subculturing on basal medium containing 0.1 or 1.0 mg BA/liter and then transferring to basal medium. Rooting occurred on basal medium. Although callus was obtained in all eight cultivars, shoots and plantlets were regenerated only from `Moriguchi', `Nerima Shirinaga', and `Comet'. Chemical names used: 2-(l-naphthyl) acetic acid (NAA); N-(phenylmethyl)-lH-purine-6-amine (BA); 2,4-dichlorophenoxy acetic acid (2,4-D); 6-(furfurylamino)purine (kinetin).
Sachiko Matsubara and Hegazi H. Hegazi
Jameel M. Al-Khayri, Feng H. Huang, and Teddy E. Morelock
Callus, induced in the dark from leaf tissue of spinach (Spinacia oleracea L. cv. Fall Green) on Murashige and Skoog (MS) medium supplemented with (in mg·liter -1) 2 kinetin and 0.5 2,4-D regenerated shoots upon transfer to a medium containing 2 kinetin, 0.01 2,4-D, and 1 GA3. Complete plants were established by stimulating rooting of the shoots with 1 mg IBA/liter and transferring them to potting soil; survival was 60%. Chemical names used: N-(2-furanylmethyl)-1H-purin-6-amine (kinetin); 2;4-dichlorophenoxy acetic acid (2,4-D); gibberellic acid (GA3); 1H-indole-3-butanoic acid (IBA).
Seong Min Woo and Hazel Y. Wetzstein
populations, and safeguarding of germplasm. An efficient plant regeneration system was developed for the micropropagation of Georgia plume using leaf tissue as the explant source ( Woo and Wetzstein, 2008 ). This method has proven suitable for field
Samir C. Debnath
The growth and development of lingonberry (Vaccinium vitis-idaea L.) plants propagated either by conventional softwood cuttings or by in vitro shoot proliferation from nodal explants and by shoot regeneration from excised leaves of micropropagated shoots, were studied in cultivars `Regal', `Splendor', and `Erntedank'. Significant differences were observed between the treatments. After 3 years of growth, the in vitro-derived plants produced more stems, leaves, and rhizomes than the conventional cuttings which rarely produced rhizomes. In vitro culture on nutrient medium apparently induces the juvenile branching characteristics that favor rhizome production. This increase in vegetative growth and rhizome yield of in vitro-derived plants over stem cuttings varied among genotypes.
Suzanne M.D. Rogers, Kalyani Dias, and David Byrne
Viral damage is a major problem in citrus. As most citrus are asexually propagated, it is necessary to have an alternative way of regenerating virus-free plants from infected plants. Shoot apicies are the most suitable explant material for this purpose because that part of the plant is virus-free. Fifty sour orange shoot tips and 22 Swingle shoot tips, 1 mm - 1.5 mm long, were excised from in vitro germinated seedlings and cultured on semisolid Murashige and Skoog medium, without growth regulators, containing 0.2 % Gelrite. After 8-10 weeks, shoots and leaves developed in 68'% of the sour orange explants, and in 77% of the Swingle explants. Some explants produced roots, after 11-12 weeks, and could be removed from culture and established in soil medium.
John R. Stommel and Stephen L. Sinden
Cultured leaf explants obtained from 36 accessions of the wild tomato species, Lycopersicon hirsutum Humb. and Bonpl., were evaluated for morphogenic capacity in response to three cytokinins (zeatin, BA, and kinetin) in combination with IAA. Media containing 0.1 μm IAA plus 4.6 or 9.2 μm zeatin were optimal for shoot induction. Cotyledon explants were superior to true leaf explants for obtaining shoot formation. Morphogenic responses of L. hirsutum f. typicum and L. hirsutum f. glabratum were clearly accession-dependent and ranged from exceptional with numerous shoots produced to recalcitrant with no shoots produced. The high morphogenetic capacity of leaf explants from L. hirsutum f. typicum accession 128644 was also evident in protoplast-derived calli that readily regenerated shoots. Chemical names used (E)-2-methyl-4-(1H-purin-6-ylamino)-2-buten-1-ol (zeatin), N-(phenylmethyl) -1H-purin-6-amine (BA), N- (2-furanylmethyl) -1H- purin-6-amine (kinetin), 1H- indole-3-acetic acid (IAA).
Mahmoud B. Arif and Houchang Khatamian
Surface sterilized stem nodal sections of western soapberry (Sapindus drummondii Hook. & Arn.) were cultured on Murashige and Skoog (MS) medium. The basal media consisted of one half and full strength MS medium each supplemented with the following (mg-1): Nicotinic acid 0.5, pyridoxine Hcl 0.5, Glycine 2.0, myo-inositol 100, sucrose 30,000 and agar 8000. Each medium also was supplemented with either 0, 0.01, 0.1, 1.0 and 10 mg/l Thidiazuron (TZD) or 0, 0.5, 2.0 and 5 mg/l 6-Benzyladenine (BA). The pH of all media was adjusted to 5.8 ± 0.1. The culture media were autoclaved at 120°C at 1.5 Kgcm-1 pressure for 15 min.
The highest percentage of nodal sections resulting in shoot regeneration occurred on 1/2 MS with TZD at 0.01 mg/l and MS medium containing 0.5 mg/l of BA Increasing the TZD concentration above 0.1 mg/l resulted in callus formation on cut surfaces.
Chiu-Yueh Hung and Jiahua Xie
create Se-enriched transgenic plants. Currently, the functional analysis of the Astragalus genes related to Se accumulation is limited because there is no transformation and regeneration system available for the Astragalus species. So far, only one
James A. Kapaun and Zong-Ming Cheng
Plants were regenerated from leaf tissue of greenhouse-grown seedlings of Siberian elm (Ulmus pumila L.). Shoot regeneration was induced on Murashige and Skoog (MS) medium containing 5 to 10 μm of BA. Up to 55% of the leaf explants formed shoots with an average of 2.4 shoots per explant. Addition of 2.5 or 5 μm of IBA failed to enhance regeneration. Thidiazuron at 0.5 or 1.0 μm also induced shoot regeneration, but the shoots failed to elongate as well as shoots regenerated from media containing BA. Incubation in darkness for 7, 14, or 21 d had little effect in promoting shoot regeneration, except that incubation for 21 d increased shoot regeneration on the medium with 5.0 μm BA. Genotypes differed in shoot regeneration potential, with regeneration frequencies ranging from 13% to 55%. Regenerated shoots were micropropagated on Driver and Kuniyuki Walnut medium. Ninety percent of microcuttings rooted directly in potting soil. This regeneration system will be valuable for genetic transformation and cell selection of Siberian elm. Chemical names used: 6-benzylaminopurine (BA); indole-3-butyric acid (IBA); N-phenyl-N′ -1,2,3-thiadiazol-5-ylurea (thidiazuron, TDZ).
Aisu Gu, Wenfang Liu, Chao Ma, Jin Cui, Richard J. Henny, and Jianjun Chen
Henny, 2008 ). In vitro propagation of Anthurium includes shoot multiplication from pre-existing meristems ( Kunisaki, 1980 ; Teixeira da Silva et al., 2005 ) or regenerated through organogenesis ( Kuehnle and Sugii, 1991 ; Martin et al., 2003