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This study investigates the formulation of surfactant-free Pickering emulsions that release a drug at a specific pH to improve its oral bioavailability. The stabilizing particles composed of magnesium carbonate particles. Pickering oil-in-water emulsions stabilized with magnesium carbonate particles and encapsulating a hydrophobic drug model (ibuprofen) were formulated using a high-energy process with rotor-stator turbo mixer (IKA® T25 digital ultra-Turrax). The experimental approach explored the impact of all formulation parameters, dispersed phase and amount of magnesium carbonate particles on the physicochemical properties of Pickering emulsions. The O/W Pickering emulsion was characterized by a methylene blue test, pH and conductivity measurements, and droplet size determination. In addition, Pickering emulsions stabilized by magnesium carbonate particles have the advantage of being destabilized in acidic medium leading to the release of the active principle via the droplets. The acidic medium release study (pH equal to 1.2) showed ibuprofen release as a function of initial droplet loading and saturation concentration. In the simulated intestinal medium at pH equal to 6.8, we found a better release of ibuprofen from emulsions that already had saturation in an acid medium. Thus, the interest of these Pickering emulsions lies on the fact that their non-toxicity and magnesium carbonate particles allow destabilization of the emulsions and release of the drug. These emulsions not only protect patients from the side effects of acid-based drugs, but also contribute to increase the bioavailability of these acidic drugs. Keywords: emulsion -Pickering-magnesium carbonate- ibuprofen-oral bioavailability

Background Cowpea, Vigna unguiculata, is an important food legume in the tropics and subtropics. However, cowpea is a complex species with more than 10 subspecies which can hybridize and produce intermediate progenies. Partly because of the complex organization of the cowpea gene pool and the lack of adequate markers for these infraspecific units, cowpea breeders are not using the wild part of the cowpea gene pool. Methods Here, we report the molecular characterization of 34 representative accessions with 61 SSR markers from coding regions. Results If SSR failed to separate the closest groups, i.e. subsp. alba, subsp. tenuis and the perennial groups from subsp. unguiculata, a combination of few SSR markers can properly identify the main cowpea subspecies. Regarding the infraspecific phylogeny of cowpea, SSR markers confirm the special status of the annual subsp. unguiculata versus the different perennial subspecies. It confirms that subsp. protracta looks like the oldest subspecies, making the origin of the species in southern Africa likely. However, it unites in a single group, clearly separated from subsp. unguiculata, all the taxa of hybrid origin, i.e. subsp. alba, subsp. tenuis, subsp. pubescens and the BWA group of subsp. unguiculata. Conclusion Although a limited number of markers was tested considering that several hundred of cowpea SSR are available, the present work shows that SSR markers can be used for molecular characterization of cowpea subspecies and can be very helpful for understanding its complex evolutionnary history.

BackgroundMicrosatellite markers represent a low-cost and efficient tool for rapid genotyping as compared to single nucleotide polymorphism markers in laboratories with limited resources. For the economically important yam species widely cultivated in developing countries, very few microsatellite markers are available and no marker database has been developed to date. Herein, we conducted a genome-wide microsatellite marker development among four yam species, identified cross-species transferable markers, and designed an easy-to-use web portal for the yam breeder community.ResultsThe screening of yam genomes resulted in 318,713; 322,501; 307,040 and 253,856 microsatellites inDioscorea alata,D. rotundata,D. dumetorum, andD. zingiberensis, respectively. Mono-, di- and tri-nucleotides were the most important types of repeats in the different species and a total of 864,128 primer pairs were designed. Furthermore, we identified 1170 cross-species transferable microsatellite markers. Among them, a subset of 17 markers were experimentally validated with good discriminatory power regarding the species and the ploidy levels. Ultimately, we created and deployed a dynamic Yam Microsatellite Markers Database (Y2MD) available athttp://yamdb.42web.io/. Y2MD is embedded with various useful tools such as JBrowse, Blast,insilicoPCR, and SSR Finder to facilitate the exploitation of microsatellite markers in yams.ConclusionsThe present work is the first comprehensive microsatellite marker mining across several yam species and will contribute to advance yam genetic research and marker-assisted breeding. The released user-friendly database constitutes a valuable platform for yam breeders, especially those in developing countries.

Background Asian rice Oryza sativa, first domesticated in China, is having considerable success in African fields. While the timing and location of this introduction remain unclear, rice of Asian origin may have evolved specifically during and after migration to Africa, resulting in unique adaptations, particularly in relation to upland cultivation as frequently practiced in Africa. Methods We investigated the genetic differentiation between Asian and African varieties using the 3000 Rice Genomes SNP dataset. African upland cultivars were first characterized using principal component analysis among 292 tropical Japonica accessions of both origins, revealing higher similarity with accessions from Indonesia and Madagascar. Peculiarities of African accessions were then explored using two inference techniques, PCA-KDE for supervised classification and chromosome painting, and ELAI for individual allelic dosage monitoring. Key results Ambiguities of local differentiation between Japonica and other groups pointed at genomic segments that potentially resulted from genetic exchange. Those specific to West African upland accessions were concentrated on chromosome 6 and featured several cAus introgression signals, including a large one between 17.9 and 21.7 Mb. We found iHS statistics in support of positive selection in this region and we provide a list of candidate genes enriched in GO terms for this adaptation to harsh upland cultivation conditions.

Les rhumatismes inflammatoires chroniques sont une cause importante d'invalidité dans le monde entier. De ce fait, les affections rhumatismales chroniques font peser une lourde charge sociale et économique sur toutes les sociétés, pas seulement sur celles où l’espérance de vie est élevée. L’objectif principal de ce travail était d’étudier le profil de libération pH-dépendante de principes actifs hydrophobes à partir d’oléogels oraux et/ou cutanés. La formulation des oléogels a été réalisée selon une méthode sol-gel, reproductible à grande échelle. La caractérisation et le suivi dans le temps ont montré une bonne stabilité des oléogels. Les valeurs de pH des oléogels étaient globalement acides (entre 4,3 et 5,8) et dépendaient de la quantité de gélifiant utilisée. Les études de libération du kétoprofène, principe actif hydrophobe, en fonction du pH des milieux de dissolution ont montré des profils de libération d’une cinétique du premier ordre d’équation 𝑷𝒕=𝑷𝟎+𝑨.𝒆𝒙𝒑𝑲𝒕 avec des coefficients de détermination proches de 1 (milieux à pH égal à 1,2 et 5,5). Une meilleure libération du kétoprofène a été obtenue dans un milieu intestinal simulé (pH égal à 6,8) pour les formulations qui présentaient déjà une saturation en milieu gastrique simulé (pH égal à 1,2). Cette étude qui a permis de formuler, d’évaluer et de modéliser le profil de libération du kétoprofène à partir d’oléogels peut constituer une étape importante dans un objectif de souveraineté thérapeutique des pays d’Afrique subsaharienne notamment le Sénégal.Mots clés : Oléogels, rhumatismes inflammatoires chroniques, kétoprofène, libération contrôlée, pH-dépendant. English Title: pH-dependent controlled release systems of hydrophobic active pharmaceutical ingredients from oleogels Chronic inflammatory rheumatism is a major cause of disability around the world. As a result, chronic rheumatic diseases place a heavy social and economic burden on all societies, not just those with high life expectancy. The main objective of this work was to control the pH-dependent release of hydrophobic active pharmaceutical ingredients from oral and / or skin oleogels. The formulation of the oleogels was carried out using a sol-gel large-scale reproducible method. Characterization and monitoring over time have shown good stability of the oleogels. The pH values of the oleogels were overall acid (between 4.3 and 5.8) and depended on the amount of gelling agent used. The release studies of ketoprofen, a hydrophobic active pharmaceutical ingredient, as a function of the pH of the dissolution media have shown release profiles of first-order kinetics of equation 𝑷𝒕=𝑷𝟎+𝑨.𝒆𝒙𝒑𝑲𝒕 with coefficients of determination close to 1 (media at pH equal to 1.2 and 5.5). Better release of ketoprofen was obtained in simulated intestinal medium (pH equal to 6.8) for formulations which already exhibited saturation in simulated gastric medium (pH equal to 1.2). This study, which made it possible to formulate, evaluate and model the release profile of ketoprofen from oleogels, may constitute an important step in an objective of therapeutic sovereignty of the countries of sub-Saharan Africa, particularly Senegal.Keywords: oleogels - chronic inflammatory rheumatism - ketoprofen - controlled release – pH-dependent.

Les symbioses fixatrices d’azote sont des interactions à bénéfice réciproque entre certaines espèces végétales (légumineuses et plantes actinorhiziennes principalement) et des microorganismes du sol ( r hizobium ou Frankia ). Ces symbioses contribuent de façon considérable à la nutrition azotée de ces plantes e t donc à leur développement particulièrement sur l es sols pauvres en azote . L’établissement de ces symbioses démarre par un dialogue moléculaire , puis par la formation de structures appelées nodules ou nodosités , siège des échanges entre les deux partenaires (plante et bactérie) La formation et le développement de nodules requièrent la médiation de gènes spécifiques parmi les quels figurent les régulateurs transcriptionnels ( facteurs de transcription et microARN) microARN). Des facteurs de transcription dont CYCLOPS, NSP1 et NSP2 communs entre les symbioses r hizobium légumineuse et Frankia plante actinorhizienne ont été caractérisés à d ifférents stades du développement du nodule Ils interagissent avec les protéines DE LLA pour induire l’expression du gène NIN , n écessaire à l’initiation de l’infection . Ces facteurs de transcription sont régulés par divers microARN. Cette revue résume l es types de symbioses fixatrices d’azote et les récentes avancées sur l es régulateurs transcriptionnels impliqué s dans l es étapes de pré infection, d’infection et d’organogenèse du nodule . Pour ce faire, nous avons collecté et analysé des données pertinentes de la littérature sur des études moléculaires et cellulaires des symbioses fixatrices d’azote.

Nanomedicine has been a booming industry with the development of nanovectors to encapsulate water-soluble or amphiphilic molecules for drug delivery. As the new therapeutic agents synthesized are increasingly lipophilic, the development of new nanoparticulate vectors allowing their transport and targeting is now a major challenge. These particles are lipid nanoparticles, a few hundred nanometers in diameter, stabilized by a layer of surfactants composed of castor oil and stealth agents. Solid lipid nanoparticles based on shea butter, stabilized by cremophor® ELP, encapsulating griseofulvin, were formulated by the temperature phase inversion method. The shea butter nanoparticles thus obtained were the subject of characterization relating to: determination of the morphology, size, polydispersity index, pH and zeta potential. The results confirm the stability of our preparations. The anti-inflammatory activity of shea butter being known, the tests were carried out on mice. The inflammation was induced by a solution of croton oil acetone. There is a very big improvement in anti-inflammatory activity. This is due to better penetration of the preparation through the different layers of the skin. Griseofulvin release studies have been carried out on our various preparations. Systems designed as reservoirs of active ingredients and intended for a priori controlled release obey kinetics of the order of one-half (½) corresponding to a proportionality between the quantity released and the square root of time. Shea butter in nanoparticulate forms has thus enabled us to considerably prolong the release of griseofulvin. Keywords: Nanoparticles; Shea Butter; Inflammation; Griseofulvin.

Cowpea is one of the most important legume grain in the SubSaharian region of Africa used for human consumption and animal feeding but its production is hampered by biotic and abiotic constraints raising the need to broaden its genetic basis. For this purpose, the seeds of two cowpea varieties Melakh and Yacine were respectively irradiated with 300 and 340 Gy. The developed mutant populations were agromorphologically characterized from M5 to M7 while the genetic diversity of the last were evaluated using 13 ISSR markers. Based on agromorphological characterization, variation of flower color, pod length, seed coat color and seed weight with respectively 78.01, 68.29, 94.48 and 57.58% heritability were recorded in the mutant lines. PCA analyses allowed to identify the elite mutants based on their agromorphological traits while Pearson’s correlation results revealed a positive correlation between yield component traits. Three subpopulations were identified through STRUCTURE analyses but assignment of the individuals in each group was improved using DAPC. Analysis of Molecular Variance revealed that the majority (85%) of the variance rather existed within group than among (15%) group. Finally, our study allowed to select new promising mutant genotypes which could be tested for multi local trials to evaluate their agronomic performance.

The aim of this study was to evaluate the level of protection of employees who are exposed to radiation in a level III hospital establishment. It was a descriptive cross-sectional survey of six months’ duration, involving eight level III Hospitals (Aristide Le Dantec, Fann, Hoggy, Hear, Abass Ndao, Pikine, Touba, and Thies) in Senegal. Sixty-one of the one hundred questionnaires were recovered (overall response rate of 61%). The population of the study was mainly female (54.1%). The average age was 38.57 with extremes ranging from 23 to 65 years old. In the places where ionizing radiation sources are handled, only at the Aristide Le Dantec Hospital did we find a “competent person in radiation protection”. This explained the lack of a classification of employees and work areas. Forty out of sixty-one (73.77%) had no knowledge of the basic principles of radiation protection (justification, optimisation, dose limitation) and had not ever taken radiation holidays. For radiovigilance, exposure time limits to ionizing radiation concerned only 29/61 or 47.54% of the study population. The inverse square law of distance was known by only 40 workers, of whom 15 had no compliance. We found the presence of dosifilms in only 7/61 or 11.47% of the workers. On the other hand, the use of lead aprons was well established and concerned 57/61 workers, i.e., 93.44%. In sum, ionizing radiation causes adverse health effects. The absence of a good radiation protection culture in Senegal requires the presence of at least 4 to 5 competent persons in radiation protection for quality training of workers in radiobiology, radiopathology and radiation protection.

Cowpea (Vigna unguiculata (L.)) is an important crop for food security in Senegal; therefore, understanding the genetic diversity of local germplasm is relevant for crop improvement and genetic maintenance in the era of climate change. For this purpose, 15 microsatellite markers were used to estimate the genetic diversity of Senegalese cowpea germplasm, including 671 accessions grown in eight regions and 66 wild relatives and intermediate forms (weedy). For the cultivated, the main expected heterozygosity (mHe) ranged between 0.317 (Fatick) and 0.439 (South). A narrow genetic variation between accessions from the different regions was observed with genetic similarity ranging from 0.861 to 0.965 and genetic differentiation indices (Fst) between 0.018 and 0.100. The accessions from southern Senegal (Kédougou, Sédhiou, and Kolda regions) are more diverse than the others. However, the accessions from the North (Saint-Louis) are genetically different from other regions. The diversity analysis in wild relatives from Senegal, which had never been performed before, revealed that the wild/weedy forms remain more diverse than the cultivated with genetic diversity values (He) of 0.389 and 0.480, respectively. STRUCTURE software divided the Senegalese germplasm into five subpopulations. Three of them (i, ii, and iii) included only cultivated accessions from several regions, one (v) mainly from Saint-Louis, and one (iv) the wild/weedy with some cultivated accessions. Our results support the hypothesis that Vigna unguiculata var. spontanea is the wild progenitor of cowpea. The accessions from the South, the northern recession accessions, and the wild/weedy could serve as sources of new genes for the genetic improvement of cowpea in Senegal.

This study was done to determine the mid-parent heterosis, the general (GCA) and specific (SCA) combining abilities of storage root yield, sweet potato virus resistance (SPVD), flesh color and vine weight of candidate sweet potato clones. Sixteen selected genotypes from two gene pools were crossed in an 8B×8A cross having 64 families. Trials were conducted with 1,896 offsprings and 16 parents during two seasons at the National Crops Resources Research Institute in Uganda (NaCRRI) using a Westcott design (only checks were replicated). Significant differences in performance were noted among families for all traits in both seasons (P ≤ 0.001). Magabali×NK259L and Resisto×Naspot 7 were the best crosses for improving total storage root while Naspot 5×Naspot 7 stood out as the best cross for flesh color. The ratio of general combining ability to specific combining ability (GCA/SCA) for storage root, flesh color and SPVD ranged from 0.55 to 0.79, implying that additive gene effects were more important than non-additive gene effects for these traits. For vine weight, non-additive gene effects tended to be predominant. A susceptible parent Magabali and a moderately susceptible parent Naspot 1 had the most resistant progenies. This suggests that SPVD resistant alleles could be homozygous recessive, which may be confirmed in further studies. Correlation studies between traits were almost all significant except for flesh color and storage root yield. There was a positive and significant correlation (P ≤ 0.001) between flesh color and SPVD resistance, with orange roots being the most resistant to SPVD. This important finding can help breeders to come up with orange-fleshed sweet potatoes that are highly resistant to virus diseases. Key words: Sweet potato combining ability, heterosis, genetic effect, storage root, sweet potato virus resistance (SVDP), flesh color, vine weight.

Introduction: Fatigue fractures are secondary to excessive, unusual, repeated mechanical stress, occurring on healthy bone. Bone scintigraphy (BS) with 99mTc-HMDP is an excellent means of diagnosis. We report a case of stress fracture of the calcaneus with scintigraphic diagnosis, in a marathon runner. Patient and Methods: He is a 40-year-old athlete in overtraining with right calcaneal pain on running, intense at first, moderate in the middle and then persistent after exercise. The interrogation found no trauma to the right foot and the x-ray of the foot was without abnormality. The so 3 phases were performed following an injection of 564 MBq of 99mTc-HMDP, with a SPECT gamma camera. Results: Bone scintigraphy found in the early phase, hyper-perfusion and hyper-fixation of the right calcaneal region compared to its left counterpart and in the bone phase persistence of focal hyperfixation opposite the right calcaneus. This scintigraphic aspect of the right calcaneus in an overtrained marathon runner, in a painful context and in front of a normal X-ray, made us evoke a fracture of fatigue. A complementary CT scan performed two days after the BS was without abnormality. Conclusion: Fatigue fractures are micro-fractures generally not noticed on radiography and CT. BS due to its high sensitivity is an excellent or the best tool for the early diagnosis of stress fractures.

Multiple emulsions are of great therapeutic interest especially in the administration of medicines which can be inactivated by digestive enzymes; moreover the researches of formulation not being often easy, a control of the different phases physicochemical parameters would be of great interest in rapid formulations and at low cost. When formulating emulsions, the preliminary tests, also known as formulation tests, constitute a step which can be long and expensive because of the quantity of reagents that can be used. A rigorous methodology could thus be of great interest, which is at the aim of our study which consists of evaluating the physico-chemical parameters of different phases used to make thus multiple emulsions. In our study, physico-chemical parameters such as conductivity, pH, density, viscosity, and surface tension have been studied by direct measurement using equipment and also by means of suitable mounting. The results showed that the pH and the surface tension have an important role in the prediction of the stability of emulsions, these latter must be of the same order of magnitude. For all phases conductivity does not have too much interest apart from helping to determine the type of the emulsion.

Sorghum is a staple food for many in the Sahel. However, it often faces earlystage water deficit resulting in production decrease. Research is focusing on developing early drought tolerant varieties. This study assessed the effects of early drought stress on 10 elite varieties of West African sorghum collection tested over 2 years (2018-2019) in Bambey (Senegal). Water stress was applied by withholding irrigation 25 days after sowing for one month, followed by optimal irrigation until maturity. Soil moisture and agro-physiomorphological traits were monitored. Results showed highly significant effects of early drought stress on sorghum plants growth. The combined analysis of variance revealed highly significant differences (P ≤ 0.01) between varieties in the different environments for most traits studied. Under water deficit, the genotypic adaptation was linked to the capacity of varieties to increase the dead leaves weight and the roots length density and to reduce photosynthesis rate, stomata conductance, and leaf transpiration. The analysis of spectral indices across water treatments revealed significant variation. However, the differential responses between varieties remained the same. Fadda (V1), Nieleni (V2), Soumba (V8) and 621B (V9) showed promising behavior under drought stress and could be suitable for further use in West Africa.

Water deficit stress at the early stage of development is one of the main factors limiting pearl millet production. A practice to cope with would be to apply hormones to stimulate plant growth and development. Exogenous methyl jasmonate (MeJA) can improve drought tolerance by modulating key pathways, therefore, we assumed that can occur in pearl millet during the early stage of development. To decipher the molecular mechanisms controlling these pathways, RNAseq was conducted in two pearl millet genotypes, drought-sensitive SosatC88 and drought-tolerant Souna3, in response to 200 µM of MeJA. Transcriptomic analysis between the MeJA-treated and non-treated plants revealed 3270 differentially expressed genes (DEGs) in SosatC88 and 127 DEGs in Souna3. Gene ontology (GO) classification assigned most regulated DEGs in SosatC88 to heme binding, oxidation-reduction process, response to oxidative stress and membrane, and in Souna3 to terpene synthase activity, lyase activity, magnesium ion binding, and thylakoid. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis reveals that DEGs in SosatC88 are related to the oxidation-reduction process, the biosynthesis of other secondary metabolites, the signal transduction, and the metabolism of terpenoids, while in Souna3, DEGs are related to the metabolism of terpenoids and the energy metabolism. Two genes encoding a diterpenoid biosynthesis-related and a Glutathione S transferase T3 were contra-regulated between SosatC88 and Souna3. Additionally, five random genes differentially expressed by RNAseq were validated using qPCR. These insights into the molecular mechanisms of pearl millet genotype tolerance at the early stage of development contribute to the understanding of the role of hormones in adaptation to drought-prone environments.

Water deficit stress at the early stage of development is one of the main factors limiting pearl millet production. One practice to counteract this limitation would be to resort to the application of hormones to stimulate plant growth and development at critical stages. Exogenous methyl jasmonate (MeJA) can improve drought tolerance by modulating signaling, metabolism, and photosynthesis pathways, therefore, we assumed that can occur in pearl millet during the early stage of development. To decipher the molecular mechanisms controlling these pathways, RNAseq was conducted in two pearl millet genotypes, drought-sensitive SosatC88 and drought-tolerant Souna3, in response to 200 μM of MeJA. Pairwise comparison between the MeJA-treated and non-treated plants revealed 3270 differentially expressed genes (DEGs) among 20,783 transcripts in SosatC88 and 127 DEGs out of 20,496 transcripts in Souna3. Gene ontology (GO) classification assigned most regulated DEGs in SosatC88 to heme binding, oxidation–reduction process, response to oxidative stress and membrane, and in Souna3 to terpene synthase activity, lyase activity, magnesium ion binding, and thylakoid. The Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis reveals that DEGs in SosatC88 are related to the oxidation–reduction process, the biosynthesis of other secondary metabolites, the signal transduction, and the metabolism of terpenoids, while in Souna3, DEGs are related to the metabolism of terpenoids and the energy metabolism. Two genes encoding a diterpenoid biosynthesis-related (Pgl_GLEAN_10009413) and a Glutathione S transferase T3 (Pgl_GLEAN_10034098) were contra-regulated between SosatC88 and Souna3. Additionally, five random genes differentially expressed by RNAseq were validated using qPCR, therefore, they are potential targets for the development of novel strategies breeding schemes for plant growth under water deficit stress. These insights into the molecular mechanisms of pearl millet genotype tolerance at the early stage of development contribute to the understanding of the role of hormones in adaptation to drought-prone environments.

Summary Unlike most of the important food crops, sesame can survive drought but severe and repeated drought episodes, especially occurring during the reproductive stage, significantly curtail the productivity of this high oil crop. Genome‐wide association study was conducted for traits related to drought tolerance using 400 diverse sesame accessions, including landraces and modern cultivars. Ten stable QTLs explaining more than 40% of the phenotypic variation and located on four linkage groups were significantly associated with drought tolerance related traits. Accessions from the tropical area harboured higher numbers of drought tolerance alleles at the peak loci and were found to be more tolerant than those from the northern area, indicating a long‐term genetic adaptation to drought‐prone environments. We found that sesame has already fixed important alleles conferring survival to drought which may explain its relative high drought tolerance. However, most of the alleles crucial for productivity and yield maintenance under drought conditions are far from been fixed. This study also revealed that pyramiding the favourable alleles observed at the peak loci is of high potential for enhancing drought tolerance in sesame. In addition, our results highlighted two important pleiotropic QTLs harbouring known and unreported drought tolerance genes such as SiABI4, SiTTM3, SiGOLS1, SiNIMIN1 and SiSAM. By integrating candidate gene association study, gene expression and transgenic experiments, we demonstrated that SiSAM confers drought tolerance by modulating polyamine levels and ROS homeostasis, and a missense mutation in the coding region partly contributes to the natural variation of drought tolerance in sesame.

Sorghum is the fifth most important cereal crop world-wide and feeds millions of people in the Sahel. However, it often faces early-stage water deficit due to false onsets of rainy seasons resulting in production decrease. Therefore, developing early drought tolerant material becomes a necessity but requires a good knowledge of adaptation mechanisms, which remains to be elucidated. The present study aimed at assessing the effects of early drought stress on ten elite sorghum varieties tested over two years (2018–2019) at the National Agronomic Research Centre (CNRA) of Bambey (Senegal, West Africa). Two different water regimes (well-watered and drought stress) were applied during the dry season. Water stress was applied by withholding irrigation 25 days after sowing for one month, followed by optimal irrigation until maturity. Soil moisture measurements were performed and allowed to follow the level of stress (down to a fraction of transpirable soil water (FTSW) of 0.30 at the end of stress). An agro-physio-morphological monitoring was carried out during the experiment. Results showed highly significant effects of early drought stress in sorghum plants growth by decreasing leaf appearance, biomass, height but also yield set up. The combined analysis of variance revealed highly significant differences (p ≤ 0.01) between varieties in the different environments for most characters. Under water deficit, the variability was less strong on leaf appearance and plant height at the end of stress. The adaptation responses were related to the capacity of varieties to grow up fast and complete their cycle rather, increase the dead leaves weight, reduce photosynthesis rate, stomatal conductance, leaf transpiration and increase the roots length density. However, varieties V1, V2, V8 and V9 showed promising behavior under stress and could be suitable for further application in West Africa for sorghum breeding and farming.

Background Pearl millet, a nutritious food for around 100 million people in Africa and India, displays extensive genetic diversity and a high degree of admixture with wild relatives. Two major morphotypes can be distinguished in Senegal: early-flowering Souna and late-flowering Sanio. Phenotypic variabilities related to flowering time play an important role in the adaptation of pearl millet to climate variability. A better understanding of the genetic makeup of these variabilities would make it possible to breed pearl millet to suit regions with different climates. The aim of this study was to characterize the genetic basis of these phenotypic differences. Results We defined a core collection that captures most of the diversity of cultivated pearl millets in Senegal and includes 60 early-flowering Souna and 31 late-flowering Sanio morphotypes. Sixteen agro-morphological traits were evaluated in the panel in the 2016 and 2017 rainy seasons. Phenological and phenotypic traits related with yield, flowering time, and biomass helped differentiate early- and late-flowering morphotypes. Further, using genotyping-by-sequencing (GBS), 21,663 single nucleotide polymorphisms (SNPs) markers with more than 5% of minor allele frequencies were discovered. Sparse non-negative matrix factorization (sNMF) analysis confirmed the genetic structure in two gene pools associated with differences in flowering time. Two chromosomal regions on linkage groups (LG 3) (~ 89.7 Mb) and (LG 6) (~ 68.1 Mb) differentiated two clusters among the early-flowering Souna. A genome-wide association study (GWAS) was used to link phenotypic variation to the SNPs, and 18 genes were linked to flowering time, plant height, tillering, and biomass (P-value < 2.3E-06). Conclusions The diversity of early- and late-flowering pearl millet morphotypes in Senegal was captured using a heuristic approach. Key phenological and phenotypic traits, SNPs, and candidate genes underlying flowering time, tillering, biomass yield and plant height of pearl millet were identified. Chromosome rearrangements in LG3 and LG6 were inferred as a source of variation in early-flowering morphotypes. Using candidate genes underlying these features between pearl millet morphotypes will be of paramount importance in breeding for resilience to climatic variability.

When formulating emulsions, the preliminary tests, also known as formulation tests, constitute a step which can be long and expensive because of the quantity of reagents that can be used. A rigorous methodology could thus be of great interest, that is at the aim of our study which consists of evaluating the physico-chemical parameters of different phases used to make thus multiple emulsions.In our study, physico chemical parameters such as conductivity, pH, density, viscosity, and surface tension have been studied by direct measurement using equipment and also by means of suitable mounting.The results showed that the pH and the surface tension have an important role in the prediction of the stability of emulsions, these latter must be of the same order of magnitude. For all phases conductivity does not have too much interest apart from helping to determine the type of the emulsion.STATEMENT OF SIGNIFICANCEMultiple emulsions are of great therapeutic interest especially in the administration of medicament which can be inactivated by digestive enzymes, moreover the researches of formulation not being often easy, a control of the physicochemical parameters of the different phases would be of great interest in rapid formulations and at low cost.

Additional file 1: Table S1. List of accessions from the Senegalese pearl millet core collection. Table S2. Representativeness statistics of early-flowering Souna morphotype and late-flowering Sanio morphotypes within the core collection. %MD = Percentage of mean difference, %VD = Percentage of variance difference, %CR = Coincidence rate, and %VR = Variable rate. Table S3. Means, P-values and correlation with axis from the discriminant analysis (DA) of early- and late- flowering millets. Table S4. Significantly associated SNPs from GWAS, mapped in the pearl millet genome and associated with phenotypic traits. Figure S1. Genetic structure of Senegalese pearl millet landraces core collection at chromosome level (a-g) from chromosome 1 to chromosome 7, respectively. Figure S2. Discriminant analysis of (a) early-flowering (Axis1 = 98.49, Axis2 = 1.51) and (b) late-flowering morphotypes (Axis1 = 95.59, Axis2 = 4.41), from phenotypic traits of landraces from the core collection. Boxplots of (c) grain yield, (d) panicle yield, (e) spike thickness, (f) nodal tillering and (g) flag leaf length according to different subsets of early-flowering morphotype. Boxplots of (h) panicle yield, (i) grain yield and (j) nodal tillering according to different subsets of late-flowering morphotype.

Sesame is an important oilseed crop in Africa and Asia, owing to its high nutritional quality seed and market value. Variation in sesame seed components including oil, oleic acid, linoleic acid, and protein was investigated by near-infrared reflectance spectrometry in 139 samples collected from different countries. Oil and protein contents were between 40.8% and 60.3% (mean 53.0%) and 15.5% to 25.5% (mean 20.4%), respectively. Linoleic acid, ranging from 31.8% to 52.4% (mean 46%) was more abundant than oleic acid (31.8%–50.6%, mean 38.1%). Light-seeded samples displayed higher nutritional quality, as they were richer in oil, protein, and linoleic acid than dark seeds. Samples from Africa had higher oil and linoleic acid contents, while Asian samples had higher oleic content. The analysis revealed West African sesame cultivars containing especially high levels of seed components, which may command high market values. Two clusters of sesame samples grouped by seed composition were obtained, including one cluster with high oil and oleic acid content and the other with high protein and linoleic acid content. This study revealed that sesame samples from Africa and Asia harbor high variation for major seed components and also provided background information for breeding high-nutrition varieties according to the demands of sesame seed markets.

Pickering emulsions are systems without surfactants, stabilized by solid particles. These emulsions are experiencing a renewed interest, on the one hand, because it is preferable to limit the use of synthetic surfactants for toxicological and environmental reasons and, on the other hand, the need to make new formulations in order to control the drug release patterns by encapsulation or controlled release. Thus, we were interested in the formulation and evaluation of W / O Pickering emulsions stabilized by particles of magnesium oxide with tramadol hydrochloride in the internal phase. The Bancroft rule served as a model for the formulation. The emulsification was carried out by progressively adding an aqueous phase dispersed in an oil-dispersing phase using a turbo rotor stator mixer. The stability of these emulsions was studied using several parameters (droplet size, pH, viscosity, conductivity...) and the qualitative and quantitative analysis of the active ingredient by UV-visible spectrophotometry. The results obtained showed that the dye test and the conductivity measurement confirmed the W / O nature of these emulsions. Some parameters such as droplet size, pH and viscosity were strongly influenced by the amounts of Magnesium oxide particles and the active ingredient. The qualitative and quantitative analysis of the active ingredient confirmed the presence of tramadol in the internal aqueous phase. Thus, we have succeeded in developing a stable W / O Pickering emulsion with magnesium oxide particles. In addition, we were able to encapsulate tramadol in the dispersed aqueous phase.

The cytosine DNA methylation and demethylation have a role in regulating plant responses to the environment by affecting the promoter regions of most plant defense-related genes through the CpG islands or the CCGG motifs. Salicylic acid, a defense and signaling plant hormone, is seen playing crucial role in the variation of the methylome. In this study, the effects of salicylic acid and feeding of the millet headminer (Heliocheilus albipunctella de Joannis) on pearl millet DNA methylome changes were evaluated through MSAP epigenotyping during panicle development. The results showed that millet headminer feeding increased the level of genomic methylation while application of salicylic acid caused DNA demethylation occurring mostly at external cytosine and accompanied by a decrease of the number of larvae per panicle. This suggests that hemimethylation (external cytosine methylation) has key role in regulating defense responses and conferring tolerance to pearl millet through salicylic acid application.