Variations in agronomic and grain quality traits of rice grown under irrigated lowland conditions in West Africa

Rice breeding in West Africa has been largely skewed toward yield enhancement and stress tolerance. This has led to the variable grain quality of locally produced rice in the region. This study sought to assess variations in the agronomic and grain quality traits of some rice varieties grown in this region, with a view to identifying sources of high grain yield and quality that could serve as potential donors in their breeding programs. Forty‐five varieties were grown under irrigated conditions in Benin and Senegal with two trials in each country. There were wide variations in agronomic and grain quality traits among the varieties across the trials. Cluster analysis using paddy yield, head rice yield, and chalkiness revealed that 68% of the total variation could be explained by five varietal groupings. One group comprising seven varieties (Afrihikari, BG90‐2, IR64, Sahel 108, WAT311‐WAS‐B‐B‐23‐7‐1, WAT339‐TGR‐5‐2, and WITA 10) had high head rice yield and low chalkiness. Of the varieties in this group, Sahel 108 had the highest paddy yield in three of the four trials. IR64 and Afrihikari had intermediate and low amylose content, respectively, with the rest being high‐amylose varieties. Another group of varieties consisting of B6144F‐MR‐6‐0‐0, C74, IR31851‐96‐2‐3‐2‐1, ITA222, Jaya, Sahel 305, WITA 1, and WITA 2 had high paddy yield but poor head rice yield and chalkiness. The use of materials from these two groups of varieties could accelerate breeding for high yielding rice varieties with better grain quality for local production in West Africa

Overview of the Scientific, Political and Financial Landscape of Climate-Smart Agriculture in West Africa

The agricultural sector plays a key role in the Economic Community of West African States (ECOWAS). As the backbone of the economy, it affects society at many levels since national economies and people’s jobs, incomes and food security depend upon it. Climate change and variability pose a major threat to farmers in the region, which is already experiencing rising temperatures, shifting precipitation patterns, and increasing extreme events. The ECOWAS has put in place various policy instruments such as the Economic Community of West Africa States Agricultural Policy (ECOWAP) and its derived Regional Agricultural Investment Plan (RAIP) in order to promote a modern and sustainable agriculture based on effective and efficient family farms and the promotion of agricultural enterprises through the involvement of the private sector. Taking stock on member States’ expressed needs, ECOWAS would like to integrate a new type of public policy instruments into the RAIP: instruments for adapting the West-African agriculture to climate change, towards a Climate-Smart Agriculture (CSA) focusing on adaptation, mitigation and food & nutrition security joint objectives. This book documents and analyses specific features of the scientific, institutional, policy and funding CSA landscape in West Africa. It provides relevant information that could guide the definition of the ECOWAS Framework for CSA Intervention, Funding, Monitoring and Evaluation. Five major agricultural sectors have been covered: crop production, livestock, fisheries, forestry/agroforestry, and water. For each sector, a particular emphasis was given to the current status, the climate projections and likely socio- economic and environmental impacts expected, the bottlenecks to action and suggested next steps for adaptation and mitigation. Actionable messages and recommendations have been directed to ECOWAS stakeholders so as to incentivise CSA in West Africa. Key words: Climate change ; Climate-smart agriculture ; Crop production ; Livestock ; Water resources ; Fisheries ; Forestry ; Agroforestry ; West Afric

Polygala rarifolia DC., plante faux hôte du Striga hermonthica (Del.) Benth

Objectif: L’objectif est d’étudier l’efficacité biologique de Polygala rarifolia sur les graines de Striga hermonthica et la nature des extraits racinaires afin d’identifier le mode d’action.Méthodologie et résultats: La méthodologie utilisée est celle de culture in vitro et de l’Analyse par chromatographie liquide à haute pression (HPLC) des extraits racinaires du Polygala rarifolia et du niébé. Les résultats obtenus en culture in vitro confirment le mode d’action de plante faux hôte. Dans les extraits racinaires de Polygala rarifolia et de niébé on a repéré la présence de pics sur les chromatogrammes, des substances présentant des temps de rétention très voisins de ceux du Strigol et de Sorgholactone mais dont les spectres UV très différents. Celui du niébé (tr = 27,30 min) et de Polygala rarifolia (tr = 27,33 min) sont identiques donc constituent la même substance chimique. Il a été possible d’affirmer que les extraits racinaires de Polygala rarifolia contiennent des substances voisines de celles du Strigol. Pour établir que ce sont bien elles qui sont responsables de la germination des graines de Striga hermothica, il faudrait désormais associer une étude phytochimique plus approfondie à une étude d’activité et établir la formule chimique de ces substances.Conclusion et application des résultats: D’autres études complémentaires de l’activité biologique de Polygala rarifolia pourront se faire dans l’objectif de confirmer ou d’ajouter d’autres résultats non identifiés ici. Tous ces résultats forts intéressants pourront faire l’objet de mise en pratique sur le terrain par le biais de la pré vulgarisation auprès des paysans en tenant compte des conditions climatiques souvent défavorables.Mots Clés: Polygala rarifolia, Striga hermonthica, Maïs, Niébé, Faux hôte, HPLCEnglish Title: Polygala rarifolia DC. trap crop of Striga hermonthica (Del.) BenthEnglish AbstractObjective: Local knowledge in weed management exists in Burkina Faso, especially Striga hermonthica. The study was interested in the use of the plant, Polygala rarifolia, to control Striga hermonthica in maize. The objective is to study the biological efficacy of Polygala rarifolia on Striga hermonthica seeds and the nature of root extracts in order to identify the mode of action.Methodology and results: The methodology used is that of in vitro culture and analysis by high pressure liquid chromatography (HPLC) of the root extracts of Polygala rarifolia and cowpea. The results obtained in vitro culture confirm the mode of action of trap crop. In the root extracts of Polygala rarifolia and cowpea, the presence of peaks on the chromatograms, substances with retention times very close to those of Strigol and Sorgholactone but with very different UV spectra, was noted. That of cowpea (tr = 27.30 min) and Polygala rarifolia (tr = 27.33 min) are identical and therefore constitute the same chemical substance. It has been possible to say that the root extracts of Polygala rarifolia contain substances similar to those of Strigol. To  establish that they are responsible for the germination of the seeds of Striga hermothica, it would now be necessary to associate a more thorough phytochemical study with an activity study and establish the chemical formula of these substances.Conclusion and application of results: Further studies of the biological activity of Polygala rarifolia may be carried out with the objective of confirming or adding other unidentified results here. All these interesting results can be put into practice in the field through pre-extension to farmers taking into account the often unfavorable climatic conditions.Keywords:  Polygala rarifolia, Striga hermonthica, Maize, Cowpea, Trap crop, HPL

Impact of fermentation and incorporation of cashew flour on the micronutrient and macronutrient contents of millet flour sold in the market: case of the city of Yamoussoukro

The weaning period of an infant, which should begin from 7 months, is characterized by the gradual change from a liquid to a solid diet. After 6 months, the nutrients contained in breast milk are no longer sufficient to meet the growing demands of the infant. This is the ideal period for the introduction of a complementary food to make up for any deficiencies. To contribute to this situation, two groups, each consisting of five combinations of millet flour, enriched with cashew flour were formulated. The samples M100A0 (Unenriched millet flour), M92,5A7,5, M85A15, M77, 5A22,5 and M70A30 were enriched with 7.5%, 15%, 22,5% and 30% downgraded cashew flour, respectively. The samples MF100A0 (Unenriched fermented millet flour), MF92, 5A7,5, MF85A15, MF77, 5A22,5 and MF70A30 were constructed in a corresponding manner, the only difference being that the millet flour was fermented. After analyses of the different formulations, the best proportions of proteins were observed in MF70A30, MF77, 5A22, 5 and M70A30, which were 13.13%, 12.25% and 12.25%, respectively. Samples M70A30 and M77,5A22,5 exhibited the best iron contents of 8.44 ppm and 8.12 ppm, respectively. The protein contents of the unfortified samples M100A0 and MF100A0 were 7.53% and 6.13% respectively. Formulations MF70A30, M77,5A2,5 and M70A30 with levels of 1.06 ppm, 0.98 ppm and 0.98 ppm, respectively, gave the best zinc contents. The moisture contents of the formulated samples had minimal changes. They varied between 6.16 ± 0.06% and 7.6 ± 0.99% for unfermented samples, and between 6.35 ± 0.32% and 7.0 ± 0.02% for fermented samples. The humidity values of the two groups of samples were not significantly different at P≤0.05. These low moisture contents in the flours are important for better preservation. At the end of this study, certain formulations were selected because of their good nutritional profile. Thus the formulations M70A30 composed of 70% millet flour and 30% cashew flour and MF70A30 composed of 70% fermented millet flour and 30% cashew flour present the best options and could be used as quality infant flours.&nbsp

HIV infection and mycobacterium tuberculosis drug-resistance among tuberculosis patients in Burkina Faso, West Africa

The aim of this study was to compare the drug-resistance patterns of Mycobacterium tuberculosis strains among pulmonary tuberculosis patients, according to their HIV serostatus, in Burkina Faso. Tuberculosis (TB) patients were classified in new and previously treated cases by using a structured questionnaire. Susceptibility testing to isoniazid, streptomycin, rifampicin and ethambutol was done by the proportion method. Association between HIV-serostatus and drug-resistant TB was assessed with χ2 tests, and the statistical significance was set to

Hydric stress-dependent effects of Plasmodium falciparum infection on the survival of wild-caught Anopheles gambiae female mosquitoes

<p>Abstract</p> <p>Background</p> <p>Whether <it>Plasmodium falciparum</it>, the agent of human malaria responsible for over a million deaths per year, causes fitness costs in its mosquito vectors is a burning question that has not yet been adequately resolved. Understanding the evolutionary forces responsible for the maintenance of susceptibility and refractory alleles in natural mosquito populations is critical for understanding malaria transmission dynamics.</p> <p>Methods</p> <p>In natural mosquito populations, <it>Plasmodium </it>fitness costs may only be expressed in combination with other environmental stress factors hence this hypothesis was tested experimentally. Wild-caught blood-fed <it>Anopheles gambiae </it>s.s. females of the M and S molecular form from an area endemic for malaria in Mali, West Africa, were brought to the laboratory and submitted to a 7-day period of mild hydric stress or kept with water ad-libitum. At the end of this experiment all females were submitted to intense desiccation until death. The survival of all females throughout both stress episodes, as well as their body size and infection status was recorded. The importance of stress, body size and molecular form on infection prevalence and female survival was investigated using Logistic Regression and Proportional-Hazard analysis.</p> <p>Results</p> <p>Females subjected to mild stress exhibited patterns of survival and prevalence of infection compatible with increased parasite-induced mortality compared to non-stressed females. Fitness costs seemed to be linked to ookinetes and early oocyst development but not the presence of sporozoites. In addition, when females were subjected to intense desiccation stress, those carrying oocysts exhibited drastically reduced survival but those carrying sporozoites were unaffected. No significant differences in prevalence of infection and infection-induced mortality were found between the M and S molecular forms of <it>Anopheles gambiae</it>.</p> <p>Conclusions</p> <p>Because these results suggest that infected mosquitoes may incur fitness costs under natural-like conditions, they are particularly relevant to vector control strategies aiming at boosting naturally occurring refractoriness or spreading natural or foreign genes for refractoriness using genetic drive systems in vector populations.</p

Hydric stress-dependent effects of Plasmodium falciparum infection on the survival of wild-caught Anopheles gambiae female mosquitoes

<p>Abstract</p> <p>Background</p> <p>Whether <it>Plasmodium falciparum</it>, the agent of human malaria responsible for over a million deaths per year, causes fitness costs in its mosquito vectors is a burning question that has not yet been adequately resolved. Understanding the evolutionary forces responsible for the maintenance of susceptibility and refractory alleles in natural mosquito populations is critical for understanding malaria transmission dynamics.</p> <p>Methods</p> <p>In natural mosquito populations, <it>Plasmodium </it>fitness costs may only be expressed in combination with other environmental stress factors hence this hypothesis was tested experimentally. Wild-caught blood-fed <it>Anopheles gambiae </it>s.s. females of the M and S molecular form from an area endemic for malaria in Mali, West Africa, were brought to the laboratory and submitted to a 7-day period of mild hydric stress or kept with water ad-libitum. At the end of this experiment all females were submitted to intense desiccation until death. The survival of all females throughout both stress episodes, as well as their body size and infection status was recorded. The importance of stress, body size and molecular form on infection prevalence and female survival was investigated using Logistic Regression and Proportional-Hazard analysis.</p> <p>Results</p> <p>Females subjected to mild stress exhibited patterns of survival and prevalence of infection compatible with increased parasite-induced mortality compared to non-stressed females. Fitness costs seemed to be linked to ookinetes and early oocyst development but not the presence of sporozoites. In addition, when females were subjected to intense desiccation stress, those carrying oocysts exhibited drastically reduced survival but those carrying sporozoites were unaffected. No significant differences in prevalence of infection and infection-induced mortality were found between the M and S molecular forms of <it>Anopheles gambiae</it>.</p> <p>Conclusions</p> <p>Because these results suggest that infected mosquitoes may incur fitness costs under natural-like conditions, they are particularly relevant to vector control strategies aiming at boosting naturally occurring refractoriness or spreading natural or foreign genes for refractoriness using genetic drive systems in vector populations.</p

Evaluation des connaissances paysannes sur la diversité de l'entomofaune du sorgho et de l'arachide au Burkina Faso

Une enquête a été menée, de juillet à décembre 1996, dans cinq provinces productrices du sorgho et de l'arachide au Burkina Faso, pour évaluer les connaissances paysannes sur la diversité des insectes nuisibles aux deux cultures et sur leurs ennemis naturels associés. L'enquête a touché 244 personnes de cinq ethnies les plus représentées du pays. Les résultats montrent que les paysans du Burkina Faso ont une connaissance assez détaillée de la plupart des arthropodes nuisibles majeurs du sorgho et de I'arachide. En revanche, ils identifient certains arthropodes prédateurs, mais ils méconnaissent leur utilité dans la lutte contre les ravageurs des cultures. Pour protéger leurs productions, ils privilégient une lutte chimique sans précautions, au risque de s'intoxiquer et de polluer leur environnement. Il est donc nécessaire de les aider à différencier insectes nuisibles et ennemis naturels dans leurs champs, et à préserver ces derniers. (Résumé d'auteur