Caractérisation de quelques écotypes performants de sorghos Burkinabés

Cinquante-huit (58) écotypes de sorgho ont été sélectionnés dans la collection de sorghos de l’Université de Ouagadougou et caractérisés dans le cadre de l’évaluation de leur performance. Le choix des écotypes a porté sur leur productivité et les qualités liées à leur appréciation par les paysans. La caractérisation agronomique a révélé l’existence d’une très grande variabilité autour des caractères liés à la productivité. L’analyse de la matrice de corrélation a révélé des associations positives entre les caractères de production et ceux de rusticité telle l’aptitude au tallage. La comparaison réalisée avec l’évaluation de 1991 a montré des différences dont la plus importante est celle liée au rendement potentiel. L’identification des écotypes performants et des géniteurs de caractères a permis de ressortir quelques écotypes dont les qualités liées tant à la production qu’à la rusticité sont des atouts autour de quoi, l’espoir peut être fondé dans l’accroissement des productions et l’amélioration de sorghos du Burkina Faso.Mots clés : Sorghos performants, géniteurs de caractères, variabilité, productivité

Variation de caractères agromorphologiques et du Brix d’une collection de sorghos à tige sucrée du Burkina Faso

Le sorgho à tige sucrée est de nos jours une plante d’intérêt utilisée pour la production de biocarburant. Au Burkina Faso, les ressources génétiques de ce sorgho ne sont pas connues, encore moins exploitées. Pour comprendre les relations entre la concentration en sucre des tiges et les caractères agromorphologiques de cette plante, 117 accessions ont été collectées dans quatre zones agro-climatiques du Burkina Faso. La caractérisation a été faite à partir de 15 variables quantitatives et de variables qualitatives qui discriminent pour la plupart les races de sorgho cultivé. Cette étude montre que les sorghos à tige sucrée du Burkina Fasoprésentent une diversité raciale plus importante en comparaison avec ceux d’autres pays comme le Mali et la Guinée. La majorité des accessions à nervure verte (77,21% d’entre elles) ont des tiges juteuses jusqu’à la maturité physiologique des grains. Le Brix des tiges au stade grain dur varie entre 8,88 et 21,83%. Il est négativement corrélé au rendement en grains par plante. Les accessions les plus sucrées sont celles à cycle longavec une importante biomasse. Les facteurs « zone climatique » et « race botanique» contribuent tous à expliquer la diversité observée avec  cependant un effet plus important du facteur racial.© 2013 International Formulae Group. All rights reserved.Mots clés : accession, diversité agromorphologique, zone climatique, race

Évaluation de la diversité génétique des sorghos à grains sucrés (Sorghum bicolor (L.) Moench) du Nord du Burkina Faso

Objectif : L’étude a pour objectif de déterminer le niveau de diversité agromorphologique des sorghos à grains sucrés du Nord du Burkina et d’estimer les paramètres génétiques de la collection en vue d’identifier les meilleures stratégies d’amélioration variétale.Méthodologie et résultats : Les résultats de l’étude réalisée sur 37 accessions selon un dispositif blocs Fisher à trois répétitions révèlent une importante diversité morphologique structurée autour des caractères végétatifs et du rendement et une répartition des accessions en quatre groupes sur la base principalement de la hauteur de la plante et du rendement grains par plante. L’évaluation des paramètres génétiques a montré une faible différence entre les coefficients de variation phénotypique et génotypique et une héritabilité au sens large élevée pour tous les caractères. Les caractères liés au rendement ont exprimé une héritabilité au sens large et un gain génétique attendu élevé alors que les caractères végétatifs ont enregistré une héritabilité au sens large élevée et un faible gain génétique attendu. Le cycle a présenté une héritabilité au sens large élevé et un gain génétique attendu modéré.Conclusion et application : Les 4 groupes obtenus qui sont des entités constituées de pools de gènes différents pourraient servir de géniteurs pour la création de variétés répondant aux attentes des paysans. La diversité génétique observée au sein des sorghos à grains sucrés du Nord du Burkina pourrait être exploitée dans les programmes de sélection du sorgho. Les résultats de l’évaluation des paramètres génétiques permettent d’envisager l’amélioration des sorghos à grains sucrés par une méthode de sélection directe.Mots clés : Sorghos à grains sucrés, diversité agromorphologique, Nord du Burkina Fas

Landrace sorghum lines- potential sources for male sterility maintainers in hybrid parent development

The potential of hybrid sorghum to provide yield advantages under drought stressed conditions in semiarid areas was shown several authors ( Haussmann, et al., 1998, 2000, Rattunde et al., 2013). Higher yield advantages were shown with Nigerian germplasm in preliminary on-station testing (Andrews, 1975), though the parental materials have since been lost. The objective of this work is to identify suitable seed parents towards developing hybrid sorghum for the Nigerian environment, constrained most particularly by non-appropriate indigenous sources of stable malesterility maintenance on the female parents, within the diversesorghum landraces

Morphological Diversity Assessment of Nigeria Sorghum Landraces for Utilization in Hybrid Parent Development

Challenge in hybrid sorghum development for the Nigerian environment remains the identification of suitable seed parents, constrained most particularly by non-appropriate indigenous sources of stable male-sterility maintenance on the female parents. To achieve this goal, defined “functional” heterotic parental-pools is required to create new and diverse hybrid parents for sustainable hybrid development. To explore availability of male–sterility inducing cytoplasm, an exploratory landrace Sorghum collection across some states of Nigeria 2014 and 2015 were carried out and evaluated for target hybrid parent traits. 388 testcrosses generated from 40 randomly selected landraces collections using 2 male sterile lines (ICS38A and ICS24005A), were evaluated for sterility maintainer to identify lines that are suitable for conversion to male sterile lines and restorers. Preliminary characterization during 2014 cropping season evaluation showed that most of the sorghum landraces grown in the Sudan Savannah are white or yellow grain with compact elliptic panicle forms (caudatum type) accounting for 46% as compared to those in Guinea Savannah cultivating white or red grain with loose dropping panicle forms (guinea type). Result from the genomic analysis revealed wide genetic diversity with 5 major distinct clusters at 0.2 Euclidian distances. The genetic materials used as parents in the testcrosses showed high potential of genetic male sterility maintainers and were diverse, where 3 of the landrace parents were mapped to cluster 1, 13 to cluster 2, 1 to cluster 3 and 3 to cluster 5. Given that the collection areas are diverse with heterogeneous agro-ecologies, the landraces observed could be used as important sources of novel alleles for developing hybrid parents

Enhancing the capacity of smallholder farms to tap into digital climate service technologies opportunities for improved crop production in the cercles of Sikasso

In the Sahel, the agricultural sector, based mainly on rainfed farming system is extremely sensitive to climate change due to the higher frequency of excess heat, and changes in rainfall patterns leading to crop failure and crop damages from pests and diseases. In Mali, this threat of climate change is of particular concern as 80% of the population is engaged in agriculture and livelihoods, and are largely dependent on natural resources that are constantly degrading. Based on this observation, our approach was to help a group of 100 farmers to better integrate climate information and agricultural advice into their production systems through the Sénékèla/Sandji platform in the cercles of Sikasso and Kadiolo. A user group of 10 to 15 farmers was set up in seven (7) villages. The constitution of these groups took into account all social strata, including women who are the most marginalized in rural areas. Producers were trained in the use of the system (registration, interpretation of messages, holding a conversation with the agroadvisor). By using the platform, the farmers were able to better plan their activities, make decisions based on climate forecasts and have access to agricultural advice in real time. To evaluate the system, a study was conducted with a sample of 68 producers; the methodology adopted was based on data collection through a questionnaire and two rating sheets given to producers. The results show that the technology has had a positive impact on the lives of beneficiaries. We have seen a decrease in production costs of more than 30%, better use of inputs for 72% of producers and a decrease in working time (60.3% of producers). The majority of users (88%) are satisfied with Sénékèla/Sandji as a tool for disseminating climatic information, and 71% of forecasts received by producers were confirmed, which proves the effectiveness of the system

Molecular Markers for Sensitive Detection of Plasmodium falciparum Asexual Stage Parasites and their Application in a Malaria Clinical Trial.

Plasmodium falciparum parasite life stages respond differently to antimalarial drugs. Sensitive stage-specific molecular assays may help to examine parasite dynamics at microscopically detectable and submicroscopic parasite densities in epidemiological and clinical studies. In this study, we compared the performance of skeleton-binding protein 1 (SBP1), ring-infected erythrocyte surface antigen, Hyp8, ring-exported protein 1 (REX1), and PHISTb mRNA for detecting ring-stage trophozoite-specific transcripts using quantitative reverse transcriptase polymerase chain reaction. Markers were tested on tightly synchronized in vitro parasites and clinical trial samples alongside established markers of parasite density (18S DNA and rRNA) and gametocyte density (Pfs25 mRNA). SBP1 was the most sensitive marker but showed low-level expression in mature gametocytes. Novel markers REX1 and PHISTb showed lower sensitivity but higher specificity for ring-stage trophozoites. Using in vivo clinical trial samples from gametocyte-negative patients, we observed evidence of persisting trophozoite transcripts for at least 14 days postinitiation of treatment. It is currently not clear if these transcripts represent viable parasites that may have implications for clinical treatment outcome or transmission potential

Genetic Potentials of Landrace Sorghum Genotypes for Enhanced Micronutrient(Iron and Zinc) Nutrition in West Africa

Micronutrient malnutrition, is one of greatest global challenges of our times with devastating consequences on health. Commonly used interventions associated with high cost and short-term benefits includes: nutrient supplementation, dietary diversification, commercial fortification, nutritional education and agricultural interventions

Antibodies to malaria vaccine candidates are associated with chloroquine or sulphadoxine/pyrimethamine treatment efficacy in children in an endemic area of Burkina Faso

<p>Abstract</p> <p>Background</p> <p>Patient immune status is thought to affect the efficacy of anti-malarial chemotherapy. This is a subject of some importance, since evidence of immunity-related interactions may influence our use of chemotherapy in populations with drug resistance, as well as assessment of the value of suboptimal vaccines. The study aim was to investigate relationship between antibodies and anti-malarial drug treatment outcomes.</p> <p>Methods</p> <p>Some 248 children aged 0.5 and 15 years were recruited prior to the high malaria transmission season. Venous blood (5 ml) was obtained from each child to measure antibody levels to selected malaria antigens, using ELISA. Blood smears were also performed to assess drug efficacy and malaria infection prevalence. Children were actively followed up to record clinical malaria cases.</p> <p>Results</p> <p>IgG levels to MSP3 were always higher in the successfully treated group than in the group with treatment failure. The same observation was made for GLURP but the reverse observation was noticed for MSP1-19. Cytophilic and non-cytophilic antibodies were significantly associated with protection against all three antigens, except for IgG4 to MSP1-19 and GLURP.</p> <p>Conclusion</p> <p>Acquired anti-malarial antibodies may play an important role in the efficacy of anti-malarial drugs in younger children more susceptible to the disease.</p

QTL mapping and validation of fertility restoration in West African sorghum A1 cytoplasm and identification of a potential causative mutation for Rf2

Abstract Key message Major A 1 cytoplasm fertility restoration loci, Rf 2 and Rf 5 , were found in the West African sorghum. A potential causative mutation for Rf 2 was identified. KASP markers were validated on independent material. Abstract To accelerate the identification and development of hybrid parental lines in West African (WA) sorghum, this study aimed to understand the genetics underlying the fertility restoration (Rf) in WA A1 cytoplasmic male sterility system and to develop markers for a routine use in WA breeding programs. We genotyped by sequencing three F2 populations to map the Rf quantitative trait loci (QTL), validated the molecular KASP markers developed from those QTL in two F2:3 populations, and assessed the most promising markers on a set of 95 R- and B-lines from WA breeding programs. Seven QTL were found across the three F2 populations. On chromosome SBI-05, we found a major fertility restorer locus (Rf5) for two populations with the same male parent, explaining 19 and 14% of the phenotypic variation in either population. Minor QTL were detected in these two populations on chromosomes SBI-02, SBI-03, SBI-04 and SBI-10. In the third population, we identified one major fertility restorer locus on chromosome SBI-02, Rf2, explaining 31% of the phenotypic variation. Pentatricopeptide repeat genes in the Rf2 QTL region were sequenced, and we detected in Sobic.002G057050 a missense mutation in the first exon, explaining 81% of the phenotypic variation in a F2:3 population and clearly separating B- from R-lines. The KASP marker developed from this mutation stands as a promising tool for routine use in WA breeding programs