Urban agricultural land use and characterization of mosquito larval habitats in a medium-sized town of Côte d'Ivoire

En Côte d’Ivoire, les pressions exercées sur les terres agricoles ont réduit la durée des jachères naturelles dominées par une végétation herbacée et dont la présence constitue une opportunité pour l’amélioration de la fertilité azotée des sols et la reconstitution minérale des sols dégradés. Pour cette étude, un inventaire floristique des légumineuses herbacées spontanées les plus répandues dans les jachères en constitution ont été effectuées suivie de la caractérisation physicochimique des échantillons du sol sous ces légumineuses ou non (témoin). Au total 6 espèces appartenant à deux familles (Fabaceae et Mimosaceae) et quatre genres (Calopogonium, Centrosema, Crotalaria et Pueraria) ont été inventoriées. Toutes ces espèces sont des Phanérophytes constitués majoritairement de lianes (83%) contre une minorité d’herbacées (17%). Le rapport C/N a varié de 09,5 à 12,8, demeurant ainsi dans la norme (9-12). Les sols prélevés sont quasi riches en matière organique (>1,30 g kg-1) à l’exception de celui recueilli sous Mimosa invisa (1,18±1,1g kg-1). La matière organique intervient dans les mécanismes de la libération de l’azote minéral, donc de la nutrition de la culture associée. Elle influe selon sa nature sur les propriétés physico-chimiques et biologiques du sol et a la capacité d’emmagasiner les réserves en eau.Mots clés : jachères naturelles, légumineuses subligneuses, inventaire, fertilisation, Côte d’Ivoire English title: Effects of six most common spontaneous legumes in natural fallows on soil fertility in the region of Daloa (Côte d’Ivoire)In Côte d'Ivoire, pressures on agricultural land have reduced the duration of natural fallows dominated by herbaceous vegetation and whose presence constitutes an opportunity for improving the nitrogen fertility of soils and the mineral replenishment of degraded soils. For this study, a floristic inventory of the most recurrent spontaneous herbaceous legumes colonizing these fallows in constitution was carried out followed by the physicochemical characterization of the soil samples under these legumes or not (control). A total of six species belonging to two families (Fabaceae and Mimosaceae) and four genera (Calopogonium, Centrosema, Crotalaria and Pueraria) were inventoried. All these species are Phanerophytes made up mainly of lianas (83%) against a minority of herbs (17%). The C / N ratio varied from 09.5 to 12.8, thus remaining within the norm (9-12). The soils sampled are almost rich in organic matter (> 1.30 g kg-1) with the exception of that collected under Mimosa invisa (1.18 ± 1.1 g kg-1). Organic matter is involved in the mechanisms of the release of mineral nitrogen, and therefore of the nutrition of the associated crop. Depending on its nature, it influences the physicochemical and biological properties of the soil and has the capacity to store water reserves.Keywords: Natural fallows, sublimers legumes, inventory, fertilization, Côte d’Ivoire.

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Insecticide Resistance Patterns and Mechanisms in Aedes aegypti (Diptera: Culicidae) Populations Across Abidjan, Côte d’Ivoire Reveal Emergent Pyrethroid Resistance

Journal of Medical Entomology ◽

10.1093/jme/tjab045 ◽

2021 ◽

Author(s):

Lucien Yao Konan ◽

Welbeck Achille Oumbouke ◽

Urbain Garhapié Silué ◽

Ibrahima Zanakoungo Coulibaly ◽

Jean-Claude Tokou Ziogba ◽

...

Keyword(s):

Aedes Aegypti ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Pyrethroid Resistance ◽

Population Based ◽

Cote D’Ivoire ◽

Low Frequencies ◽

Larval Habitats ◽

Côte D'ivoire ◽

The City

Abstract From 2008 to 2017, the city of Abidjan, Côte d’Ivoire experienced several Aedes-borne disease epidemics which required control of the vector mosquito population based on the reduction of larval habitats and insecticidal sprays for adult mosquitoes. This study was undertaken to assess the insecticide susceptibility status of Aedes aegypti (Linnaeus) in the city of Abidjan. Immature Ae. aegypti were sampled from several larval habitats within seven communes of Abidjan and reared to adults. Three to five days old F1 emerged adults were tested for susceptibility using insecticide-impregnated papers and the synergist piperonyl butoxide (PBO) following WHO bioassay guidelines. The results showed that Ae. aegypti populations from Abidjan were resistant to 0.1% propoxur, and 1% fenitrothion, with mortality rates ranging from 0% to 54.2%. Reduced susceptibility (93.4–97.5% mortality) was observed to 0.05% deltamethrin, 0.75% permethrin, 0.05% lambda-cyhalothrin, 5% malathion, and 0.8% chlorpyrifos-methyl. This reduced susceptibility varied depending on the insecticide and the collection site. The restoration of mortality when the mosquitoes were pre-exposed to the synergist PBO suggests that increased activity of oxidases could be contributing to resistance. Three kdr mutations (V410L, V1016I, and F1534C) were present in populations tested, with low frequencies for the Leu410 (0.28) and Ile1016 (0.32) alleles and high frequencies for the Cys1534 allele (0.96). These findings will be used to inform future arbovirus vector control activities in Abidjan.

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Characterization of malaria transmission during military crisis in urban area of Bouake, Central Cote d’Ivoire

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2014.03.642 ◽

2014 ◽

Vol 21 ◽

pp. 103

Author(s):

A.M. Adja ◽

M.C. Yobo ◽

S.B. Assi

Keyword(s):

Malaria Transmission ◽

Urban Area ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

Cote D’Ivoire ◽

Côte D'ivoire

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Agromorphological characterization of three (3) hybrid carrot varieties (Daucus carota), cultivated in the commune of Korhogo, in northern Côte d'Ivoire

International Journal of Advanced Engineering Research and Science ◽

10.22161/ijaers.4.10.14 ◽

2017 ◽

Vol 4 (10) ◽

pp. 81-88

Author(s):

Coulibaly Lacina Fanlégué ◽

Siene Laopé Ambroise Casimir ◽

Kouame Konan ◽

Coulibaly Namongo Adama

Keyword(s):

Cote D'ivoire ◽

Daucus Carota ◽

Côte D’Ivoire ◽

Cote D’Ivoire ◽

Côte D'ivoire

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Artisanal Mining Practice and Physical Impacts on the Environment in the Ity-Floleu Gold Region, Côte d'Ivoire

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2021/v11i1130513 ◽

2021 ◽

pp. 17-31

Author(s):

Sandotin Lassina Coulıbaly ◽

Franck Michaël Zahui ◽

Lydie Clarisse Mangoua-Allali ◽

Awa Cherif ◽

Lacina Coulibaly

Keyword(s):

Flow Velocity ◽

Cote D'ivoire ◽

Côte D’Ivoire ◽

River Flow ◽

Agricultural Land ◽

River Sediments ◽

Cote D’Ivoire ◽

Water Flow Velocity ◽

Artisanal Mining ◽

Côte D'ivoire

This paper describes artisanal gold mining practices and environmental impacts around the Ity-Floleu gold mine, in western Côte d'Ivoire. Interviews and field observations as well as measurements of turbidity and water flow velocity in the section of the river (Cavally) watering the study area, made it possible to identify 13 artisanal mining sites, housing 247 artisans, operating in groups made up mainly of 5 to 10 people. The activity is dominated by local populations from the villages of Ity and Floleu and the surrounding communities. Gold mined comes from alluvial and vein ores, with a predominance of alluvial ore, extracted in the sediments of the bed and the banks of the river and in the soils, inside forests. In the bed of the river, sediments are dredged using machines placed on boats, from where they are washed in mats and then dumped into the watercourse. On the other hand, on the banks of the river and in the forests, the material used consists of picks, dabas, mats, and shovels. In all cases, gold is recovered as a concentrate of gold powder. As regards vein ores, they are also extracted along with the soils of cultivable land, but in the form of blocks of stone which are crushed and washed. The gold is then recovered using mercury, followed by cyanidation. The techniques used lead to the silting up and the fall of the banks of the river, reduction of agricultural land, and the degradation of the environment by the tailings. The Cavally River appears to be strongly impacted in the midstream part of the Ity-Floleu axis, marked by a decrease in the bed and the river flow velocity (0.19 m/s) and higher turbidity (255.3 NTU). More effective policies are urgently needed to restore degraded ecosystems, both aquatic and terrestrial.

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Identification of Susceptible Weed Hosts of Phytophthora spp. in Cocoa Trees in the Nawa Region, South-West of Côte d'Ivoire

Annual Research & Review in Biology ◽

10.9734/arrb/2021/v36i130333 ◽

2021 ◽

pp. 53-65

Author(s):

Daniel Kouamé Kra ◽

Yapi Richmond Baka ◽

David Coulibaly N’golo ◽

Ipou Joseph Ipou

Keyword(s):

Cote D'ivoire ◽

Côte D’Ivoire ◽

Brown Rot ◽

Ageratum Conyzoides ◽

Cote D’Ivoire ◽

Susceptible Host ◽

Phytophthora Spp ◽

Côte D'ivoire ◽

Weed Hosts

The cocoa tree, the mainexport crop in Côte d'Ivoire is frequently attacked by a disease: brown pod rot, caused by Phytophthora spp. which causes a considerable drop in production. This soil-borne pathogen attacks on so-called weeds when environmental conditions are favourable. The presence of these susceptible weed hosts can amplify this scourge of brown rot by transmitting the pathogen to the crop plant. In order to improve the yield of this crop, a study was conducted in the Nawa region to identify the weed hosts through the characterization of the pathogen. This study consisted first in the inventory of susceptible host weeds of Phytophthora spp. and second in the morphological characterization of the pathogen. Concerning the host weeds inventory we procceeded determining all symptomatic weeds located within 3 m of the cocoa plants affected by brown rot. We identified 48 susceptible host species, divided into 41 genera and 22 families and we observed brown spots on the leaves of Oplismenus burmannii and Laportea aestuans; on the leaves of Clerodendrum splendens and Xanthosoma mafaffa, brown necroses surrounded by a yellow halo were noticed. Oily brown spots were examined on the leaves of Ageratum conyzoides. On the proximal, lateral and distal parts of the pods symptoms of brown spots covered with whitish mycelia were observed. Phytophthora strains obtained from the pods and weeds on PDA culture medium were characterized by matted, white mycelial colonies with a cottony appearance. Microscopic features revealed the presence of sporocysts, oospores and chlamydospores of different shapes.

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