Hormonal influence on the in vitro bud burst of some cassava varieties and accessions from Benin

This work tested the effect of different growth regulators on Manihot esculenta explants cultured. Nodal segments were disinfected and cultivated on Murashige and Skoog’s basal media. The effects of the different combinations on bud burst were observed after five weeks of culture. The results show an interaction between the growth regulators and the genotypes of the varieties and accessions. Most of the varieties and accessions (Gbèzé, Kpètévikoutou, Ibadan and Sèkandji) obtained the maximal bud burst in the media MS supplemented with 0.2 mg/l BAP and MS supplemented with 0.2 mg/l KIN. However, with segments cultivated in medium, containing 0.2 mg/l KIN, 1 in 15 showed bud burst for the accession Agric Comé. Naphthalene acetic acid effect varied according to the genotype and the cytokinin used, whereas on 0.1 mg/l NAA combined with 0.2 mg/l with the variety 92/0057, 14 in 15 budded. However, no bud burst was observed with 0.1 mg/l NAA combined with 0.2 mg/l BAP.Keywords: In vitro culture, Manihot esculenta Crantz, bud burst, NAA, BAP, KinetinAfrican Journal of Biotechnology Vol. 12(13), pp. 1475-148

PRODUCTION ET ACCLIMATATION DE PLANTS DU GROS BASILIC (OCIMUM GRATISSIMUM) REGENERES IN VITRO : EFFET DE L’ACIDE NAPHTALENE ACETIQUE (ANA) SUR L’ENRACINEMENT

The present work aims to study the effect of Naphthalene Acetic Acid (NAA) on the rooting and acclimatization of Ocimum gratissimum plantlets. The cutting contain one knot (Explants) used are from the plantlets of first generation R0 of Ocimum gratissimum in the stage of multiplication and aged between 4 and 6 weeks. Explants (1cm) were inoculated on half Murashige and Skoog (MS/2) supplemented with 20g/L of sucrose and 7g/L of agar with different concentrations of Naphthalene Acetic Acid NAA (0; 0.5; 1 and 2mg/L) for root induction. After eight (8) weeks of culture, the rooting rate, the number of roots formed and the length of the primary root is determined by counting of roots by plantlets and the measuring of root length is made by a ruler. The experimental design was constituted of four tests with two repetitions. Each test includes 15 tubes represented treatments. The results showed that MS medium diluted to half and supplemented with 2mg/L NAA supports the root induction (4.70±0.5) while that with 1mg/L of NAA has produced the lowest average of roots (2.70±0.5). In acclimatization, 80% of rooted plants are able to survive. The conditions for successful rooting techniques in vitro under the effect of NAA (2mg/L) followed by the production of acclimated plants can be used for other research work on essential oils from plantlets of the specie studied

EFFET DU CHARBON ACTIF SUR LA CONSERVATION DE LA VARIETE DE MANIOC (MANIHOT ESCULENTA) RB 89509 MENACEE D’EXTINCTION AU BENIN.

In situ conservation of different cultivars of cassava (Manihot esculenta) implies many problems such as climatic risks, diseases, devastators and financial difficulties. This work contributes to the maintenance of RB 89509 variety of Manihot esculenta through in vitro culture. Two cultures media were used: medium of Murashige and Skoog (MS) and medium of Murashige and Skoog (MS) added with activated carbon. The effects of activated carbon were studied on the growth parameters (number of leaves, number of roots, number of nodes, height of stem, length of internodes, length of principal root) of plantlets aged of twenty months. The results show that the average number of leaves, the average number of nodes and the length of main root are more significant at the plantlets present on medium containing the activated carbon; while the number of roots, the height of stem and the length of internodes are more significant at the plantlets present on medium without activated carbon. Moreover, it is noted an drying of the plantlets on the medium without activated carbon. The activated carbon allowed a better conservation of the plantlets

RÉGÉNÉRATION IN VITRO DE L’ARBRE À SUIF (PENTADESMA BUTYRACEA SABINE), UNE ESPÈCE LIGNEUSE À USAGES MULTIPLES (LUM) VULNÉRABLE AU BENIN

This work is done in order to identify the effects of basal media associated with two cytokinins (BAP and zeatin) and suitability for the regeneration of apical and axillary buds Pentadesma butyracea. Fragments axillary bud stem and apical bud stem fragment were taken from seedlings P. butyracea from seed germination in a greenhouse. After disinfection, explants were cultured on three basic areas: MS (Murashige and Skoog), B5 (Ganborg) and WPM (Woody Plant Medium). The effects of Zeatin and BAP on the bud and bud development were also studied. These in vitro propagation of tests conducted in this species, showed that the apical bud fragments proved to be the most favorable. Among the tested culture media, basal medium Gamborg (B5) is most suited to the entry into operation of apical buds (26.66%). Other WPM and MS basal media also allowed bud but at low rates (20%; 13%). Zeatin (3.5 mg / L) appears best suited to budding and regeneration of apical buds of P. butyracea and the formation of leaves per explants. BAP favored the resumption of activity of the apex, but not plant development. Our experiments allow to open a new path consistent multiplication of individuals elites Pentadesma butyracae to produce seeds that can be used for propagation, domestication and conservation of this species

PRODUCTION ET ACCLIMATATION DE PLANTS DU GROS BASILIC (OCIMUM GRATISSIMUM) REGENERES IN VITRO : EFFET DE L’ACIDE NAPHTALENE ACETIQUE (ANA) SUR L’ENRACINEMENT

The present work aims to study the effect of Naphthalene Acetic Acid (NAA) on the rooting and acclimatization of Ocimum gratissimum plantlets. The cutting contain one knot (Explants) used are from the plantlets of first generation R0 of Ocimum gratissimum in the stage of multiplication and aged between 4 and 6 weeks. Explants (1cm) were inoculated on half Murashige and Skoog (MS/2) supplemented with 20g/L of sucrose and 7g/L of agar with different concentrations of Naphthalene Acetic Acid NAA (0; 0.5; 1 and 2mg/L) for root induction. After eight (8) weeks of culture, the rooting rate, the number of roots formed and the length of the primary root is determined by counting of roots by plantlets and the measuring of root length is made by a ruler. The experimental design was constituted of four tests with two repetitions. Each test includes 15 tubes represented treatments. The results showed that MS medium diluted to half and supplemented with 2mg/L NAA supports the root induction (4.70±0.5) while that with 1mg/L of NAA has produced the lowest average of roots (2.70±0.5). In acclimatization, 80% of rooted plants are able to survive. The conditions for successful rooting techniques in vitro under the effect of NAA (2mg/L) followed by the production of acclimated plants can be used for other research work on essential oils from plantlets of the specie studied

EFFET DU CHARBON ACTIF SUR LA CONSERVATION DE LA VARIETE DE MANIOC (MANIHOT ESCULENTA) RB 89509 MENACEE D’EXTINCTION AU BENIN.

In situ conservation of different cultivars of cassava (Manihot esculenta) implies many problems such as climatic risks, diseases, devastators and financial difficulties. This work contributes to the maintenance of RB 89509 variety of Manihot esculenta through in vitro culture. Two cultures media were used: medium of Murashige and Skoog (MS) and medium of Murashige and Skoog (MS) added with activated carbon. The effects of activated carbon were studied on the growth parameters (number of leaves, number of roots, number of nodes, height of stem, length of internodes, length of principal root) of plantlets aged of twenty months. The results show that the average number of leaves, the average number of nodes and the length of main root are more significant at the plantlets present on medium containing the activated carbon; while the number of roots, the height of stem and the length of internodes are more significant at the plantlets present on medium without activated carbon. Moreover, it is noted an drying of the plantlets on the medium without activated carbon. The activated carbon allowed a better conservation of the plantlets

RÉGÉNÉRATION IN VITRO DE L’ARBRE À SUIF (PENTADESMA BUTYRACEA SABINE), UNE ESPÈCE LIGNEUSE À USAGES MULTIPLES (LUM) VULNÉRABLE AU BENIN

This work is done in order to identify the effects of basal media associated with two cytokinins (BAP and zeatin) and suitability for the regeneration of apical and axillary buds Pentadesma butyracea. Fragments axillary bud stem and apical bud stem fragment were taken from seedlings P. butyracea from seed germination in a greenhouse. After disinfection, explants were cultured on three basic areas: MS (Murashige and Skoog), B5 (Ganborg) and WPM (Woody Plant Medium). The effects of Zeatin and BAP on the bud and bud development were also studied. These in vitro propagation of tests conducted in this species, showed that the apical bud fragments proved to be the most favorable. Among the tested culture media, basal medium Gamborg (B5) is most suited to the entry into operation of apical buds (26.66%). Other WPM and MS basal media also allowed bud but at low rates (20%; 13%). Zeatin (3.5 mg / L) appears best suited to budding and regeneration of apical buds of P. butyracea and the formation of leaves per explants. BAP favored the resumption of activity of the apex, but not plant development. Our experiments allow to open a new path consistent multiplication of individuals elites Pentadesma butyracae to produce seeds that can be used for propagation, domestication and conservation of this species