Hormonal requirement and tissue competency for shoot organogenesis in two cultivars of Brassica napus

Abstract

G. 1992. Hormonal requirement and tissue competency for shoot organogenesis in two cultivars of Brassica napus. -Physiol. Plant. 84: 521-530.An investigation of the regeneration ability of explants taken from the floral stem of Brassica napus var. oleifera was performed in the winter cultivars Darmor and Bienvemi. Our purpose was to compare the regeneration ability of the two genotypes, to compare the competence of the different tissues of the stem and then to study histologically the regeneration of shoots. A strong genotypic effect was observed between the two cvs; Bienvenu had a poorer ability to produce shoots when cultured in the presence of benzyladenine: regeneration commenced later; the percentage of explants producing shoots and the number of shoots per regenerating explant were much lower. The comparison between the regeneration ability of different explants, i.e. stem segments, internal stem segments, thin cell layer and peels, showed that the superficial tissues were able to regenerate roots but not shoots. Contrariwise,, internal stem segments regenerated only shoots. The origin of shoots was investigated in stem segments of cv, Darmor, A kinetic histological analysis showed the basic role played by phloem and phloem-associated cells in shoot formation.

Organogenesis from internode‐derived nodules of Humulus lupulus var. Nugget (Cannabinaceae): histological studies and changes in the starch content

“…Some of these could ultimately differentiate vascular elements. This sclerified layer has been already described during shoot organogenesis from stem explants of Brassica napus (Julliard et al, 1992) and seemed to isolate the actively growing cortical cells from the internal pith, a role also played by this sclerified layer on cultured Humulus lupulus var. Nugget explants.…”

“…The heavy accumulation of starch in shoot-forming tissues has been reported in several studies (Thorpe, Joy, and Leung, 1986;Mangat, Pelekis, and Cassels, 1990;Redway, 1991;Julliard et al, 1992) and seems to precede any formation of shoot primordia. Internodal explants of Humulus lupulus var.…”

“…The differences in organogenic response of different types of explants from several hop varieties revealed a strong genotypic influence (Batista, Sousa, and Pais, 1996). Intraspecific differences in organogenic response have been reported earlier (Narasimhulu and Chopra, 1988;Julliard et al, 1992). However, both histological studies and starch accumulation/mobilization cycles revealed that the regeneration process in Humulus lupulus var.…”

Kinetics of 14C-labelled sucrose, myo-inositol and phosphatidylcholine uptake during induction and differentiation in Brassica napus callus culture

“…One of a very interesting pathway of plant morphogenesis is callus-mediated organogenesis. In Brassica napus, organogenesis was achieved from numerous types of explants (Julliard et al 1992), however the great genotypic variation of regeneration ability was reported. As a result, efficient shoot differentiation was achieved in a limited number of genotypes only (Ono et al 1994).…”

Utility of in Vitro Propagation for Field-grown Broccoli: Effect of Genotype and Growing Season

“…The brief interval from explant to shoot and the minimal callusing of explants also reduces the potential for somaclonal variation to alter genotypes. In addition, these in vitro methods can be used with gene transfer methods (Fry et al, 1987) and in shoot induction and morphogenesis studies (Julliard et al, 1992).…”