Regeneration of the tropical legume Aeschynomene sensitiva Sw. from root explants

Regeneration of #Aeschynomene sensitiva Sw. after callogenesis was obtained form small (2-5 mm long) root explants of 30-day-old seedlings aseptically cultivated on Murashige and Skoog medium supplemented with various concentrations of growth regulators. After 4 weeks, the best results were observed with 0.54 microM alpha-naphthaleneacetic acid and 2.22 microM benzyladenine. On this medium, the rate of regeneration depended on seedling age and agar concentration. The highest number of shoots per explant was obtained with small cuttings from 30-day-old seedlings grown on a medium containing 8 g/l of agar. Regeneration success was also dependent on explant size. When longer explants (7-20 mm) were cut from the main root, direct regeneration was obtained in two weeks. These cuttings also generated shoots through callogenesis in four weeks but always in lower quantities than with direct regeneration, whatever the seedling age. Here also, the best regeneration was obtained with cuttings from 30-day-old seedlings maintained on a medium with 8 g/l of agar. Regenerants were rooted on growth-regulator-free Murashige and Skoog medium and then acclimatized in a greenhouse. A better survival to transplantation was observed when plantlets were inoculated with the photosynthetic #Bradyrhizobium strain ORS 278. Stem and root nodules developed on the inoculated plantlets and were able to fix nitrogen. (Résumé d'auteur

CARACTERISATION DES BRADYRHIZOBIUM PHOTOSYNTHETIQUES ENDOPHYTES DU RIZ SAUVAGE ORYZA BREVILIGULATA

MONTPELLIER-SupAgro La Gaillarde (341722306) / SudocSudocFranceF

B.brassicae data file

The file encompasses the complete life table data of Brevicoryne brassicae monitored at 10, 15, 20, 25, 30, and 35 degree celcius on Marcanta cabbage cultiva

Variable phylogeographic histories of five forest birds with populations in Upper and Lower Guinea: Implications for taxonomy and evolutionary conservation

This study evaluates phylogeographic structure in selected forest bird species distributed on either side of the Dahomey Gap in West Africa to extend analyses of avian diversification across the Guineo-Congolean forest. Mitochondrial DNA sequence data were collected for five species, including four with a break in distribution across the Dahomey Gap and one with a more continuous distribution. Data for the five focal species were included in a single analysis along with appropriate outgroup taxa, allowing estimates of divergence time on a common timescale. Both phylogeographic patterns and estimated divergence times were highly variable. In two cases (Green Hylia Hylia prasina and Yellow-whiskered Greenbul Eurillas latirostris), samples from east and west of the Dahomey Gap belong to divergent mitochondrial lineages, but with substantially older divergence in Eurillas (~4.1 MY). In Western Bluebill Spermophaga haematina, relatively divergent eastern and western lineages (~1.1 MY) were sampled in the same locality in eastern Ghana, suggesting east to west gene flow across the gap following earlier vicariance. In Forest Robin Stiphrornis erythrothorax, birds sampled within Ghana were from two highly divergent lineages (~1.9 MY), one of which is more closely related to birds from Cameroon and Equatorial Guinea, such that divergence across the Dahomey Gap was comparatively recent (~0.36 MY). For both Hylia and Stiphrornis, we corroborate recent studies documenting multiple divergent lineages within each genus, some of which may represent distinct species. Consistent with previous studies, our analysis shows that the Dahomey Gap can be a significant barrier to gene flow for species restricted to forest habitats. At the same time, individual species exhibit a broad range of divergence times and phylogeographic histories of variable complexity. We discuss the taxonomic implications of our results for each focal species.Histoires phylogéographiques variables de cinq oiseaux forestiers ayant des populations en Haute et Basse Guinée: implications pour la conservation taxonomique et évolutiveCette étude évalue la structure phylogéographique de certaines espèces d’oiseaux forestiers réparties de part et d’autre du Dahomey Gap en Afrique de l’Ouest, pour étendre les analyses de la diversification aviaire à travers la forêt guinéo-congolaise. Les données des séquences d’ADN mitochondrial ont été collectées pour cinq espèces, dont quatre présentant une rupture dans la distribution au niveau du Dahomey Gap alors que une espèce a une distribution beaucoup plus continue. Les données pour les cinq espèces étudiées ont été incluses dans une seule analyse, ensemble avec les taxons de groupes externes appropriés, permettant d’estimer le temps de divergence sur une échelle temporelle commune. Les tendances phylogéographiques tout comme les temps de divergence estimés, étaient hautement variables. Dans deux des cas (l’Hylia verte Hylia prasina et le Bulbul à moustaches jaunes Eurillas latirostris), des échantillons provenant de l’est et de l’ouest du Dahomey Gap appartiennent à des lignées mitochondriales divergentes, mais avec une divergence sensiblement plus ancienne chez Eurillas (~4,1 MA). Chez le Sénégali sanguin Spermophaga haematina, les lignées orientales et occidentales relativement divergentes (~1,1 MA, ont été échantillonnées dans la même localité, à l’est du Ghana, suggérant un flux génique de l’est à l’ouest à travers le Dahomey Gap suivant la précédente vicariance. Pour le Rougegorge de forêt Stiphrornis erythrothorax, les oiseaux échantillonnés au Ghana appartenaient à deux lignées très divergentes (~ 1,9 MA), dont l’une était plus proche des oiseaux du Cameroun et de la Guinée équatoriale, en sorte que la divergence à travers le Dahomey Gap était relativement récente (~ 0,36 MA). Pour Hylia et Stiphrornis, nous corroborons les études récentes documentant de multiples lignées divergentes au sein de chaque genre, dont certaines peuvent représenter des espèces distinctes. En accord avec des études précédentes, notre analyse montre que le Dahomey Gap peut constituer une barrière importante au flux de gènes pour les espèces restreintes aux habitats forestiers. Aussi, les espèces considérées individuellement, présentent une large gamme de temps de divergence et des histoires phylogéographiques d’une complexité variable. Nous examinons les implications taxonomiques de nos résultats pour chaque espèce étudiée.Keywords: Dahomey Gap, Guineo-Congolean forest, phylogeography, speciation, vicarianc

Data from: Effect of temperature on the biological parameters of the cabbage aphid Brevicoryne brassicae

The cabbage aphid, Brevicoryne brassicae Linnaeus is a pest of many plants of the Brassicaceae family including cabbage, Brassica olearacae Linnaeus, 1753. We investigated the effect of temperature on the biological parameters of B. brassicae using different temperature-based models incorporated in the Insect Life Cycle Modelling software (ILCYM). Nymphs of first stage were individually placed in the incubators successively set at 10C, 15C, 20C, 25C, 30C, and 350C; 75±5% RH and L12: D12 hours photoperiods. We found that 1st nymph reached the adult stage after 18.45±0.04 days (10°C), 10.37±0.26 days (15°C), 6.42±0.07 days (20°C), 5.076±0.09 days (25°C) and 5.05±0.10 days (30°C); and failed at 35°C. The lower lethal temperatures for B. brassicae were 1.64C, 1.57C, 1.56C, and 1.62°C with a thermal constant for development of 0.88, 0.87, and 0.08, 0.79 degree/day for nymph I, II, III and IV respectively. The temperature 10, 30 and 35°C were more lethal than 15, 20 and 25°C. Longevity was highest at 10°C (35.07±1.38 days). Fertility was nil at 30°C and highest at 20°C (46.36±1.73 nymphs/female). The stochastic simulation of the models obtained from the precedent biological parameters revealed that the life table parameters of B. brassiace were affected by the temperature. The net reproduction rate was highest at 20°C and lowest at 30°C. The average generation time decreased from 36.85±1.5 days (15°C) to 6.86±0.1 days (30°C); the intrinsic rate of increase and the finite rate of increase were highest at 25°C. In general, the life cycle data and mathematical functions obtained in this study clearly illustrate the effect of temperature on the biology of B. brassicae. This knowledge will contribute to predicting the changes that may occur in a population of B. Brassiace in response to temperature variation

Biochemical aspects of single-node cuttings of Ricinodendron heudelotii (Baill.) in relation with rooting

Ricinodendron heudelotii (Njansang) is a valuable multipurpose tree species retained for domestication in Central and Western African regions. To measure the ability of rooting in relation with biochemical changes, basal single-node leafy cuttings were treated with different concentrations of indole-3-butyric acid (IBA), and 1-naphthaleneacetic acid (NAA) and cultured in fine sand media under poly-propagator system. The adventitious rooting was obtained in three distinct stages: Induction (0 to 20 days), initiation (20 to 30 days) and expression (30 to 40 days). Rooting response was higher within nodal cuttings pretreated with IBA than those pretreated with NAA. Polyphenoloxidase activity started to increase both in treated and control cutting during the initiation stage of the experiment and decreased after root emergence only in treated cuttings. Indole-3 acetic acid (IAA)-oxidase activity of auxin treated cuttings decreased as compared to the control. The peroxidase activity in IBA-treated cuttings increased slowly at the initiation stages and lightly at the expression stage. Total phenolic content was higher in IBA-treated cutting particularly at the initiation and expression stages. Phenolics andpolyphenoloxidase might be playing key role for emergence of adventitious rooting and can be used as rooting enhancer in R. heudelotii.Keywords: Auxins, enzyme activity, nodal cutting, Ricinodendron heudelotii, vegetative propagationAfrican Journal of Biotechnology Vol. 12(10), pp. 1049-105

Two new 30-norfriedelane triterpenes from Caloncoba glauca (P. Beauv.) Gilg (Achariaceae)

Ndoumbe Tamba C, Tsopgni WDT, Fotso BSH, et al. Two new 30-norfriedelane triterpenes from Caloncoba glauca (P. Beauv.) Gilg (Achariaceae). Natural Product Research . 2023.The chemical investigation of the methanolic root extract of Caloncoba glauca (P. Beauv.) Gilg exhibited two new 30-norfriedelane triterpenes, glaucalactones A and B (1-2), together with eight known compounds, caloncobalactone (3), friedelin (4), friedelanol (5), 3-oxo-friedelan-28-oic acid (6), stigmasterol (7), beta-sitosterol (8), beta-sitosterol-3-O-beta-D-glucopyranoside (9) and pentacosanoic acid (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. All the compounds were tested for their antioxidant, antifungal and antibacterial activities. Compound 1 displayed weak antibacterial effect with MIC value of 125mug/mL against Staphylococcus aureus and Escherishia coli. Compound 6 exhibited moderated antifungal activity against Candida krusei with MIC value of 62.5mug/mL. All the isolates were found to be inactive as antioxidants in the DPPH, ABTS and FRAP assays