Dégâts des bruches sur le pouvoir germinatif des graines de quatre variétés de Niébé infesté pendant 60 jours à Ngandajika

Objectif: L’objectif de cette étude est de déterminer l’impact des dégâts des bruches sur le pouvoir germinatif des graines de niébé et d’identifier des variétés résistantes ou tolérantes aux attaques de bruches pendant le stockage. Le bruche (Callosobruchus maculatus) est un petit coléoptère doté de taches sombres sur les élytres. C’est un parasite qui s’attaque aux graines pendant l’emmagasinage.Méthodologie et résultats: Au cours de ce travail, nous avons étudié le comportement de quatre (4) variétés améliorées de niébé (Yamashi, Mujilanga, IT82D-889 et Diamant) sélectionnées par l’Institut National d’Études pour la Recherche Agronomiques centre de Ngandajika sur le développement de Callosobruchus maculatus infesté dans les graines de ces variétés. Cette étude était menée in vitro au laboratoire du centre de Recherche de l’INERA Ngandajika. Les résultats révèlent que le taux d’accroissement des bruches infestés pendant 60 jours varie de 50.41% à 91.99%. Et la variété Diamant à présenté un pouvoir germinatif beaucoup plus faible 0.75% que les trois autres variétés (Mujilanga 7.75%, Yamashi 8.25% et IT82D-889 12.75%.Conclusion et application des résultats: Cette étude a permis de conclure que la variété Diamant a perdu le pouvoir germinatif après une durée de conservation de 60 jours. Ces résultats suggéreraient que pour une période de conservation après récolte, les graines de niébé de la variété Diamant ne peuvent plus être considérées comme semences. Il est par conséquent important de demander aux producteurs de semences de cette variété de ne pas utiliser la semence de cette variété après 60 jours de conservation sans traitement phytosanitaire et d’utiliser ainsi la semence fraichement récoltée.Mots clés: pouvoir germinatif, résistance variétaleEnglish AbstractObjective: The objective of this study is to determine the impact of damage from weevils on the germination of the seeds of cowpea and identify varieties resistant or tolerant to attack by weevils during storage. Callosobruchus maculatus. The weevil (Callosobruchus maculatus) is a small beetle with dark spots on the wing covers. This parasite attacks the seeds during storage. Methodology and results: During this work, we studied the behaviour of four (4) improved varieties of cowpea (Yamashi, Mujilanga, IT82D-889 and Diamond) selected by the National Research Institute for Agronomic Research centre on the development Ngandajika of Callosobruchus maculatus infested in the seeds of these varieties. This study was conducted in vitro laboratory research centre INERA Ngandajika. The results reveal that the rate of increase of weevils infested for 60 days ranged from 50.41% to 91.99%. Diamond and variety germination presented a much lower 0.75% than the other three varieties (Mujilanga 7.75%, 8.25% and IT82D Yamashi-889 12.75%.Conclusion and application of results: This survey permitted to conclude that the variety Diamant lost the germinating power after a length of conservation of 60 days. These results would suggest that for one period of conservation after harvest, the seeds of cowpea of the variety Diamant could not be considered more like seeds. It is therefore important to ask the producers of seeds of this variety to not to use the seed of this variety after 60 days of conservation without phytosanitary treatment and to use the freshly harvested seed.Keywords: germinating power, variety resistanc

Clinical characteristics and outcomes of patients hospitalized for COVID-19 in Africa : early insights from the Democratic Republic of the Congo

CITATION: Nachega, J. B. et al. 2020. Clinical characteristics and outcomes of patients hospitalized for COVID-19 in Africa : early insights from the Democratic Republic of the Congo. American Journal of Tropical Medicine and Hygiene, 103(6):2419–2428, doi:10.4269/ajtmh.20-1240.The original publication is available at https://www.ajtmh.orgENGLISH ABSTRACT: Little is known about the clinical features and outcomes of SARS-CoV-2 infection in Africa. We conducted a retrospective cohort study of patients hospitalized for COVID-19 between March 10, 2020 and July 31, 2020 at seven hospitals in Kinshasa, Democratic Republic of the Congo (DRC). Outcomes included clinical improvement within 30 days (primary) and in-hospital mortality (secondary). Of 766 confirmed COVID-19 cases, 500 (65.6%) were male, with a median (interquartile range [IQR]) age of 46 (34–58) years. One hundred ninety-one (25%) patients had severe/critical disease requiring admission in the intensive care unit (ICU). Six hundred twenty patients (80.9%) improved and were discharged within 30 days of admission. Overall in-hospital mortality was 13.2% (95% CI: 10.9–15.8), and almost 50% among those in the ICU. Independent risk factors for death were age < 20 years (adjusted hazard ratio [aHR] = 6.62, 95% CI: 1.85–23.64), 40–59 years (aHR = 4.45, 95% CI: 1.83–10.79), and ³ 60 years (aHR = 13.63, 95% CI: 5.70–32.60) compared with those aged 20–39 years, with obesity (aHR = 2.30, 95% CI: 1.24–4.27), and with chronic kidney disease (aHR = 5.33, 95% CI: 1.85–15.35). In marginal structural model analysis, there was no statistically significant difference in odds of clinical improvement (adjusted odds ratio [aOR] = 1.53, 95% CI: 0.88–2.67, P = 0.132) nor risk of death (aOR = 0.65, 95% CI: 0.35–1.20) when comparing the use of chloroquine/azithromycin versus other treatments. In this DRC study, the high mortality among patients aged < 20 years and with severe/critical disease is of great concern, and requires further research for confirmation and targeted interventions.https://www.ajtmh.org/view/journals/tpmd/103/6/article-p2419.xmlPublisher's versio