A comparative structural analysis of direct and indirect shoot ...

More documents

Recommendations

Info

286 Miroslav Ovečka, Milan Bobák, Jozef Šamaj Figure 4. Indirect shoot regeneration. 2. Formation of shoot primordia. a. Morphogenesis of peripheral meristemoid cells during shoot primordia formation. Cells expanded in anticlinal direction (arrowhead) and subsequently divided periclinally (arrows). Bar = 50 µm. b. Establishment of the tunica layer on the meristemoid surface by anticlinal cell division. Bar = 50 µm. c. Histodifferentiation of the shoot apical meristem (SAM). Bar = 50 µm. d. Cell proliferation concentrated in the dome-like protomeristem. Cells located away of the centre of cell division are devoid of starch and start to vacuolate. Bar = 50 µm. e. Developed shoot bud with leaf primordia and vascular tissue (VT) in the procambium. Bar = 100 µm. f. Laticifer initials (arrows) in the procambial region of shoot apical meristem. Bar = 50 µm. g. Initial perforation of cross cell wall between two laticifer initials. Bar = 50 µm. h. Formation of articulated, anastomosing laticifer system. Note the elastic properties of longitudinal cell wall in the site of future perforation (arrow). Bar = 50 µm. i. Insertions of cell volume between future anastomosing laticifers in cross-section (arrows). Bar = 50 µm. j. Articulated, anastomosed laticifer system in shoot procambium. Bar = 50 µm. k. Articulated, anastomosed laticifer system in developing leaves of regenerated shoots. Bar = 50 µm. Figure 5. Similarity in the correlation curves between cell size and nucleus size of peripheral meristemoid cells (——) and cells of peripheral and central zones of the apical meristems in regenerated shoots (——). 30–50 cells of each zone were measured on the medium supplemented with 0.537 µmol/L of α-naphtaleneacetic acid and 0.46 µmol/L kinetin (I), or with 0.577 µmol/L indole-3-acetic acid and 2.22 µmol/L 6-benzylaminopurine (II), or growth regulator-free medium (III). Cell size values and nucleus size values are presented as planimetric values of cell and nucleus area measured from cross sections. Direct shoot formation was initiated in the culture where somatic embryos had failed to develop correctly, but maintained continuously juvenile, undifferentiated state of their cells in the root pole which were able to generate new somatic embryos (Ovečka et al. 1997/98). However, as we show here, adventitious shoots originated from the differentiated, non-dividing tissue of hypocotyl. The competent cells have to be re-activated and they enter cell division. The culture underwent spontaneous repetitive regeneration including shoot organogenesis and somatic embryogenesis (Ovečka et al. 1997/98). Some internal factors determining cell competence in the course of shoot bud regeneration have been identified, such as reduced cellulase activity in tobacco callus culture (Truelsen and Ulvskov 1995), or importance of polar auxin transport, because its inhibition by TIBA (2,3,5-triiodobenzoic acid) strongly enhanced shoot regeneration, but not somatic
Shoot regeneration in opium poppy 287 Figure 6. Mean of the cell cross section area (a), and mean of the form factor describing cell shape (b), observed during shoot regeneration in the medium supplemented with 0.537 µmol/L of α-naphtaleneacetic acid and 0.46 µmol/L kinetin. Peripheral meristemoid cells (A) were compared to cells of central and peripheral zones of regenerated shoot apical meristems (B), and central meristemoid cells (C) were compared to cells in the rib-zone of shoot apical meristems (D). Percentage amount of cells with isodiametric (a side ratio app. 1 : 1), and oval shape (side ratio up to 2 : 1) is indicated (b). The rest of the cells had a more elongated shape. Results from measurements of app. 300 cells of each selected part of meristemoids and shoot apical meristems. ** – significant at P
Page 1 and 2: J. Plant Physiol. 157. 281-289 (200
Page 3 and 4: Shoot regeneration in opium poppy 2
Page 5: Shoot regeneration in opium poppy 2
Page 9 and 10: Shoot regeneration in opium poppy 2
Page 11 and 12: M. OVECKA & M. BOBf~K point of view
Page 13 and 14: o "i J
Page 15 and 16: M. OVECKA & M. BOB,4K Fig. 1. Scann
Page 17 and 18: M. OVECKA & M. BOBAK et al. 1997/98
Page 19 and 20: M. OVECKA ,~ M. BOBAK around somati
Page 21 and 22: E Balus"ka et al.: Mitogen-activate
Page 23 and 24: E Balus'ka et al.: Mitogen-activate
Page 25 and 26: E Balugka et al.: Mitogen-activated
Page 27 and 28: Stress MAP kinase SIMK in plant tip
Page 37 and 38: Cell Biology International 27 (2003
Page 39 and 40: J. Samaj et al. / Cell Biology Inte
Page 41 and 42: 52 M. Volgger et al. Fig. 1 Zones o
Page 43 and 44: 54 M. Volgger et al. fluorescence a
Page 45 and 46: 56 M. Volgger et al. The plasma mem
Page 47 and 48: 58 M. Volgger et al. Fig. 6 a-h Aft
Page 49 and 50: 60 M. Volgger et al. other candidat
Page 51 and 52: 62 M. Volgger et al. Ovečka M, Lan
Page 53 and 54: 4202 Illéš et al. cell wall thick
Page 55 and 56: 4204 Illéš et al. Fig. 2. Effect
Page 57 and 58:
4206 Illéš et al. Fig. 5. Changes
Page 59 and 60:
4208 Illéš et al. Fig. 7. Interna
Page 61 and 62:
4210 Illéš et al. Fig. 9. Detecti
Page 63 and 64:
4212 Illéš et al. Bolte S, Talbot
show all

A comparative structural analysis of direct and indirect shoot ...

Create successful ePaper yourself

Delete template?

Save as template?