Les mécanismes de formation du limbe chez le <i>Manihot esculenta</i> : étude microchirurgicale

Médard, R.

doi:10.1139/b89-133

Cited by 5 publications

(2 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Enations can be induced by microsurgical separation of abaxial and adaxial cells in the leaf primordium (Médard, 1988). It is therefore conceivable that abnormal 6b ‐induced cell expansion leads to enations by disrupting tissue layers in the leaf primordia.…”

Section: Discussionmentioning

confidence: 99%

New plant growth‐modifying properties of the Agrobacterium T‐6b oncogene revealed by the use of a dexamethasone‐inducible promoter

et al. 2003

View full text Add to dashboard Cite

These authors contributed equally to this work. SummaryAgrobacterium 6b oncogenes induce tumours on Nicotiana glauca and enations and associated modi®ca-tions in transgenic N. tabacum plants. 2x35S-AB-6b tobacco rootstocks produced a graft-transmissible factor that induced enations in wild-type scions; the nature of this enation factor remains to be identi®ed. Here, we report on the properties of tobacco plants carrying a dexamethasone-inducible T-6b gene (dex-T-6b). Induction with dex led to complex growth modi®cations, many of which have not been reported previously. Modi®cations were only found in growing tissues; mature tissues remained unaffected. Growth could be either stimulated or inhibited. Dex induction of young plants led to morphogenetic gradients that included enations, tubular leaves and fragmented leaf primordia. Root elongation was increased or slowed down, while radial root growth was strongly enhanced. Additional cell divisions were found in the root pericycle and vasculature. Enation factor import from mature tissues did not have the same effects on growing tissues as local T-6b synthesis: normal scions grafted on induced dex-T-6b rootstocks formed enations, whereas local dex-T-6b induction at the shoot apex led to numerous dark-green spots on the abaxial side of the leaves. In leaf patch assays, the 23-kDa T-6b protein was found to move through leaves and to enter the vascular system. This and the fact that rootstocks of spontaneous tobacco enation mutants did not modify wild-type scions contrary to 6b plants indicate that the 6b protein might be the enation factor.

show abstract

Section: Discussionmentioning

confidence: 99%

New plant growth‐modifying properties of the Agrobacterium T‐6b oncogene revealed by the use of a dexamethasone‐inducible promoter

et al. 2003

View full text Add to dashboard Cite

show abstract

“…Une telle regularit6 peut Ctre obtenue chez le manioc cultivC en serre tropicale en zone tempCrCe (MCdard 1988). Ces caractCristiques font alors de cette plante un matCriel intkressant pour l'btude du dCveloppement foliaire (MCdard 1988(MCdard , 1989. Elles peuvent Ctre Cgalement importantes pour 1'Ctude du dCveloppement de zones associCes au dkveloppement foliaire, telles l'entre-noeud (MCdard et al 1992) et le bourgeon axillaire.…”

Section: Introductionunclassified

Le développement du bourgeon axillaire du Manihot esculenta

Médard¹,

Sell²,

Barnola³

1992

Can. J. Bot.

Self Cite

View full text Add to dashboard Cite

Le dCveloppement du bourgeon axillaire du Manihot esclrlenta. Can. J . Bot. 70 : 2041-2052. L'appareil vkgktatif atrien du manioc est constituC de deux sortes d'axes : sylleptiques et proleptiques. Les axillaires, aprks dktermination, peuvent suivre deux types de dtveloppement, soit un dCveloppement anticipt B l'origine des axes sylleptiques, soit un dtveloppement proleptique. Les differences morphologiques entre les deux categories d'axes s'expliquent facilement par les diffkrences d'tvolution des axillaires. Le dtveloppement proleptique s'effectue en quatre ttapes : ( i ) une phase de dttermination, (ii) une phase de latence intramkristematique, (iii) une phase d'organogenkse et (iv) une phase d'inhibition par dominance apicale. Les deuxibme et quatribrne phases n'existent pas dans le dtveloppement anticipt. La phase de latence intramkristematique est due B I'existence d'une double prtstance de l'kbauche foliaire axillante et du point vkgktatif susjacent. L'hypothkse d'un contrble de la determination et de la latence des axillaires depuis le mtristkrne apical caulinaire est discutee. Les contr8les des deux interruptions de dkveloppement, latence intramCristCmatique prtcoce et arrCt tardif par dominance de l'ensemble de l'apex, ne s'exercent pas a la mCrne Cchelle et ne sont vraisemblablement pas de mime nature. Mots clis : bourgeon axillaire, tige, dtveloppement, manioc, pioleptique, sylleptique. MEDARD, R., SELL, Y., and BARNOLA, P. 1992. Le dkveloppement du bourgeon axillaire du Marlihot esc~rlerzta. Can. J. Bot.70: 2041 -2052. The vegetative aerial apparatus of cassava consists of two kinds of axes: sylleptic and proleptic. After its determination, an axillary meristem may have either an advanced development, which characterizes a sylleptic axis, or a later development, which characterizes a proleptic axis. The morphological differences between the two categories of axes are easily explained as the result of differences in development. Proleptic development undergoes four stages: ( i ) determination, (ii) first latent period in the apical meristem, (iii) organogenesis, and (iv) second latency. The second and fourth stages do not occur in the advanced form of development. The first latent stage is due to a double precedency of both the upper part of the apical meristem and the axillary leaf primordium. The hypothesis of a control of the determination and the first latency of the axils from the whole apical meristem is discussed. The regulation of the two types of interruptions of development do not take place on the same scale and are probably not of the same type.

show abstract

The Plant's Response towards Insect Egg Deposition

Hilker¹,

Rohfritsch²,

Meiners³

2003

Chemoecology of Insect Eggs and Egg Deposition

View full text Add to dashboard Cite

Plant responses towards insect egg depositions range from changes in plant tissue to alterations of the plant's volatile bouquet. Such responses may result either in defence against herbivores or even in their protection. Defensive tissue changes in plants caused by egg depositions are known as formation of neoplasms and as hypersensitive response. Tissue changes that positively affect herbivores are induced by egg depositions of several gall forming insects. These manipulate plants to produce nutritive and protective tissues for the progeny.Indirect plant defence responses towards egg deposition do not affect the eggs or hatching larvae directly, but employ the third trophic level. Changes in the plants' volatile emission induced by insect egg deposition are known to attract egg

show abstract

Les mécanismes de formation du limbe chez le Manihot esculenta : étude microchirurgicale

Cited by 5 publications

References 0 publications

New plant growth‐modifying properties of the Agrobacterium T‐6b oncogene revealed by the use of a dexamethasone‐inducible promoter

New plant growth‐modifying properties of the Agrobacterium T‐6b oncogene revealed by the use of a dexamethasone‐inducible promoter

Le développement du bourgeon axillaire du Manihot esculenta

The Plant's Response towards Insect Egg Deposition

Contact Info

Product

Resources

About