In vitro morphogenesis in Osmunda cinnamomea. The role of the shoot apex in early leaf development

In sterile nutrient culture, shoot apices of the rhizome of Osmunda cinnamomea L., devoid of all visible foliar primordia, quickly give rise to dorsiventral leaf primordia at a presumptive leaf site (I1). It was established that these primordia were irreversibly determined as leaves. To examine the morphogenetic role of the shoot apex in governing early leaf development, this site was permanently isolated from the shoot apex by a single tangential cut. Usually, radially symmetrical shoots of indeterminate growth arose at I1 as a result of this surgery. By contrast, when organic continuity between I1 and the shoot apex was only temporarily interrupted by a cut which was subsequently allowed to heal, normally oriented dorsiventral leaf primordia formed most frequently at I1. These, too, were determined as leaves. It was concluded that the shoot apex serves as a source of determinative influences for the nascent primordium, imposing dorsiventrality and a pattern of determinate growth on the leaf site.

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Fasciation d'extrémités caulinaires du Celosia cristata (Amarantacées) cultivées in vitro

Canadian Journal of Botany ◽

10.1139/b81-186 ◽

1981 ◽

Vol 59 (8) ◽

pp. 1367-1372 ◽

Cited By ~ 3

Author(s):

D. Driss-Ecole

Keyword(s):

Indoleacetic Acid ◽

Leaf Primordia ◽

Root Initiation ◽

Salt Mixture ◽

Shoot Apices ◽

In Vitro Development ◽

Long Period ◽

Celosia Cristata ◽

Vitro Development

In vitro development of fasciation was achieved from the excised shoot apices of Celosia cristata in a 16-h photoperiod. An 8-h photoperiod produced no development. The explants consisted of the meristematic dome with two leaf primordia. The best results were obtained with a nutrient medium composed of Murashige and Skoog salt mixture, 30 g/L sucrose, 5 g/L agar, and 1 mg/L indoleacetic acid (IAA). Isolated shoot apices developed callus at the bases of the explants and numerous leaves on one, two, or three flattened and fasciated meristems. Root initiation occurred sometimes but only after a long period of culture.

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The rotated-lamina syndrome. VI. The range from partial to near-complete rotation in Tiliaceae and Sterculiaceae

Canadian Journal of Botany ◽

10.1139/b97-019 ◽

1997 ◽

Vol 75 (1) ◽

pp. 170-187 ◽

Cited By ~ 2

Author(s):

W. A. Charlton

Keyword(s):

Key Words ◽

Shoot Apex ◽

Leaf Development ◽

Leaf Primordia

The rotated-lamina syndrome is a condition most commonly found in dorsiventral shoots with distichous phyllotaxis. Typically, young laminae in bud appear to be rotated to face towards the upper side of the shoot. The syndrome arises by asymmetrical growth from leaf primordia that initially face the shoot apex in approximately the normal way. It was previously described in Tilia. Further genera of Tiliaceae and the closely related Sterculiaceae were examined for the presence of the syndrome. Altogether it was found in 9 genera of the 30 examined. The syndrome is well developed in representatives of Commersonia, Corchorus, and Pterospermum, and less well developed in Luehia seemannii. Expression of the syndrome is minimal in Luehia divaricata, Theobroma, Byttneria, and Grewia. In all cases with distichous phyllotaxis that were examined in these families, the leaf primordia show at least some asymmetry in development and consequently there appears to be a predisposition to lamina rotation within the group. The syndrome is probably becoming suppressed in cases with minimal expression. The situation in dorsiventral shoots of Corchorus and Byttneria is complicated by the presence of inflorescences that arise in a leaf-opposed position. Key words: Sterculiaceae, Tiliaceae, leaf, development, dorsiventrality, lamina rotation.

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In vitro development of isolated leaf primordia of Matteuccia struthiopteris

Canadian Journal of Botany ◽

10.1139/b85-121 ◽

1985 ◽

Vol 63 (5) ◽

pp. 916-919 ◽

Cited By ~ 2

Author(s):

P. Von Aderkas ◽

G. Hicks

Keyword(s):

Shoot Apex ◽

Root Formation ◽

Leaf Primordia ◽

The Other ◽

Secondary Development ◽

In Vitro Development ◽

Morphological Complexity ◽

Developmental Fate ◽

Vitro Development

Primordia (P2–P6) at the shoot apex were excised and cultured on Knudson's medium for a period of 4 weeks. The majority of primordia developed as leaves. The length, mass, and morphological complexity of these leaves were related to initial primordium age and height. There was a consistent trend toward the production of shorter, lighter, and less complex leaves from the younger, smaller initial explants. A second set of experiments traced the developmental fate of isolated primordia (P1–P4) over a longer period of time (12 weeks). Various kinds of secondary development were observed including bud and root development. Bud numbers decreased with primordial age. On the other hand, the rate of root formation increased.

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MICROPROPAGATION OF Helianthus maximiliani (Schrader) BY SHOOT APEX CULTURE / MICROPROPAGACION DE Helianthus maximiliani (Schrader) POR EL CULTIVO DE VAINAS DE LOS VASTAGOS / MICROPROPAGATION DE L’Helianthus maximiliani (Schrader) AU MOYEN DE LA CULTURE DE L’APEX DE LA POUSSE

Helia ◽

10.1515/helia.2001.24.34.63 ◽

2001 ◽

Vol 24 (34) ◽

pp. 63-68 ◽

Cited By ~ 1

Author(s):

Vasić Dragana ◽

Škorić Dragan ◽

Alibert Gilbert ◽

Miklič Vladimir

Keyword(s):

Silver Nitrate ◽

Shoot Apex ◽

Casein Hydrolysate ◽

Shoot Tips ◽

Nodal Segments ◽

Shoot Apices ◽

Skoog Medium ◽

Leaf Mesophyll ◽

Murashige And Skoog Medium

SUMMARYH.maximiliani was micropropagated using culture of shoot apices on modified Murashige and Skoog medium (DV). Further propagation of in vitro grown plants was done by culture of their nodal segments and shoot tips on the same medium supplemented with phloridzin, silver nitrate and casein hydrolysate (DV'). Rooting was induced by dipping the explants into IBA solution prior culture. Viable protoplasts (90%) were isolated from leaf mesophyll. These protoplasts divided (18%) in culture in agarose droplets.

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The rotated-lamina syndrome. V. Partial lamina rotation and related features in Hamamelidaceae

Canadian Journal of Botany ◽

10.1139/b94-083 ◽

1994 ◽

Vol 72 (5) ◽

pp. 626-634 ◽

Cited By ~ 3

Author(s):

W. A. Charlton

Keyword(s):

Key Words ◽

Shoot Apex ◽

Leaf Development ◽

Early Stage ◽

Leaf Primordia ◽

Leaf Base ◽

Early Stages ◽

Young Leaves

Shoots of Hamamelidaceae have been examined for the presence of the rotated-lamina syndrome, a condition in which young leaves in bud face towards one side of the shoot (normally the upper) rather than towards their own shoot apex. Early leaf development and bud organisation have been examined in representatives of eight genera with dorsiventral shoots and distichous phyllotaxis, and of four genera with radially symmetrical shoots and spiral or decussate phyllotaxis. Radially symmetrical shoots do not show any evidence of the syndrome. The distichous Corylopsis and Hamamelis species studied have leaf primordia that are asymmetrical from an early stage and show partial lamina rotation, the lamina facing obliquely towards the upper side of the bud. Mature laminae are usually asymmetrical. In Corylopsis rotation arises by torsion in the petiole region, and in Hamamelis by asymmetrical growth of the leaf base. Distichous examples without lamina rotation also have asymmetrical primordia in most cases, often have asymmetrical leaves, and all show the same asymmetrical development of the leaf base as found in Hamamelis. It is suggested that these features represent either (i) relics of rotated-lamina syndrome that was present in these cases but has been suppressed or (ii) early stages in evolution of rotated-lamina syndrome. It is suggested that suppression is the more likely interpretation. Corylopsis and Hamamelis may also be in the process of suppressing the syndrome. Key words: Hamamelidaceae, leaf, development, dorsiventrality, lamina rotation.

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In vitro morphogenesis of Sorghum bicolor (L.) moench: Efficient plant regeneration from shoot apices

Journal of Plant Physiology ◽

10.1016/s0176-1617(98)80226-5 ◽

1998 ◽

Vol 153 (5-6) ◽

pp. 719-726 ◽

Cited By ~ 37

Author(s):

Heng Zhong ◽

Wenling Wang ◽

Mariam Sticklen

Keyword(s):

Plant Regeneration ◽

Sorghum Bicolor ◽

Shoot Apices ◽

In Vitro Morphogenesis ◽

Sorghum Bicolor L

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The rotated-lamina syndrome. IV. Relationships between rotation and symmetry in Magnolia and other cases

Canadian Journal of Botany ◽

10.1139/b94-005 ◽

1994 ◽

Vol 72 (1) ◽

pp. 25-38 ◽

Cited By ~ 7

Author(s):

W. A. Charlton

Keyword(s):

Key Words ◽

Shoot Apex ◽

Leaf Development ◽

Leaf Primordia ◽

The State ◽

Axillary Buds ◽

Reverse Direction ◽

Ulmus Glabra ◽

Young Leaves

Further variations of the rotated-lamina syndrome are described in Magnolia spp. and Rhamnus imeretinus, as well as an abnormal adult shoot of Ulmus glabra without lamina rotation. All magnolias investigated show lamina rotation, but there are four possible forms of shoot symmetry: (i) dorsiventral distichous shoots with the form of rotated-lamina syndrome previously described, i.e., laminae of young leaves all face towards the same (upper) side of the bud or towards the parental axis in axillary buds; (ii) another form of dorsiventral symmetry in which lamina rotation occurs in the reverse direction; (iii) spiral phyllotaxis with laminae rotated to face up the genetic spiral; and (iv) spiral phyllotaxis with laminae rotated to face down the genetic spiral. Shoot symmetry and development of lamina rotation in leaf primordia correlate with the taxo-nomic subdivision of the genus. Shoots of R. imeretinus are dorsiventral, with leaves arranged in four ranks, and lamina rotation occurs towards the upper side of the shoot. The sense of rotation of leaf primordia reverses with a periodicity of two plastochrons. In the abnormal shoot of Ulmus without lamina rotation, phyllotaxis was distichous and leaf primordia were symmetrical. The various cases are discussed in relation to the previously erected hypothesis that control of development in dorsiventral shoots with the rotated-lamina syndrome resides in alternating states of asymmetry in the shoot apex, and the corollary that a shoot with spiral phyllotaxis and one sense of lamina rotation should result if the state of asymmetry is maintained and does not alternate. Key words: Magnolia spp., Rhamnus imeretinus, Ulmus glabra, leaf, development, dorsiventrality, lamina rotation.

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