Diversité des Champignons Mycorhiziens à Arbuscules Associés aux Cacaoyers (Theobroma cacao L.) en Côte d’Ivoire

Les champignons mycorhiziens à arbuscule vivent en symbiose avec les racines des plantes aidant celles-ci à absorber les nutriments nécessaires à leur croissance et développement. En Côte d’Ivoire, cette symbiose n’est pas prise en compte dans stratégies agroforestières à base de cacaoyer. Ce travail vise à étudier les mycorhizes associés aux cacaoyers dans les systèmes agroforestiers. Les spores et les racines de cacaoyer issus de 32 plantations de cacao localisées dans les 4 principales zones agro écologiques de production du cacao en Côte d’ Ivoire ont été analysé. La diversité, la densité des spores, les taux de mycorhization et la richesse spécifique des mycorhizes ont été déterminés. L’examen des spores met en évidence 72 morphotypes appartenant à 10 familles, 17 genres et 49 espèces de mycorhize. Claroideoglomus etunicatum est l’espèce dominante du verger cacaoyer. L’abondance des spores varie entre 10,53 à 31,24 spores.g-1 de sol pour une moyenne de 18,30 spores.g-1 de sol. Le nombre des spores est statistiquement le même à l’échelle des ZAE. Les fréquences de mycorhization des cacaoyers sont généralement élevées et oscillent entre 89,31 % à l’Ouest du verger et 92,4 % au Sud-ouest. En revanche, les intensités de mycorhization sont inférieures à 25 % dans l’ensemble du verger cacaoyer. Ces résultats indiquent que les systèmes agroforestiers à cacaoyer en Côte d’Ivoire abritent une grande diversité de CMA qui pourrait être utilisé dans divers initiatives biotechnologique en agriculture durable.  Arbuscular mycorrhizal fungi live in symbiosis with plant roots, helping them to absorb the nutrients they need for growth and development. In Côte d'Ivoire, this symbiosis is not considered in cocoa-based agroforestry strategies. The aim of this work is to study the mycorrhizal fungi associated with cocoa trees in agroforestry systems. To this end, cocoa spores and roots from 32 cocoa plantations located in the 4 main agro-ecological zones for cocoa production in Côte d'Ivoire were analysed. The diversity, spore density, mycorrhization rates, species richness and Shannon-Wiener diversity indices of CMA communities were determined. A study of the specific richness and relative abundance of 3271 CMA spores revealed 72 CMA morphotypes in the rhizosphere of cocoa trees in Côte d'Ivoire. On all the sites, 10 families, 17 genera and 49 species of CMA were recorded. Claroideoglomus etunicatum is the dominant species in the cocoa orchard. The abundance of spores in the Ivorian cocoa orchard varied between 7,89 and 17,84 spores.g-1 of soil, with an average of 13,42 spores.g-1 of soil. The number of spores was statistically the same across the ZAEs. Cocoa mycorrhization frequencies were generally high, ranging from 89,31% in the west of the orchard to 92,4% in the south-west. In contrast, mycorrhization intensities were below 25% throughout the cocoa orchard. These results indicate that cocoa agroforestry systems in Côte d'Ivoire harbour a wide diversity of CMAs that could be used in various biotecnological initiatives in sustainable agriculture

Diversité des Champignons Mycorhiziens à Arbuscules Associés aux Cacaoyers (Theobroma cacao L.) en Côte d’Ivoire

Les champignons mycorhiziens à arbuscule vivent en symbiose avec les racines des plantes aidant celles-ci à absorber les nutriments nécessaires à leur croissance et développement. En Côte d’Ivoire, cette symbiose n’est pas prise en compte dans stratégies agroforestières à base de cacaoyer. Ce travail vise à étudier les mycorhizes associés aux cacaoyers dans les systèmes agroforestiers. Les spores et les racines de cacaoyer issus de 32 plantations de cacao localisées dans les 4 principales zones agro écologiques de production du cacao en Côte d’ Ivoire ont été analysé. La diversité, la densité des spores, les taux de mycorhization et la richesse spécifique des mycorhizes ont été déterminés. L’examen des spores met en évidence 72 morphotypes appartenant à 10 familles, 17 genres et 49 espèces de mycorhize. Claroideoglomus etunicatum est l’espèce dominante du verger cacaoyer. L’abondance des spores varie entre 10,53 à 31,24 spores.g-1 de sol pour une moyenne de 18,30 spores.g-1 de sol. Le nombre des spores est statistiquement le même à l’échelle des ZAE. Les fréquences de mycorhization des cacaoyers sont généralement élevées et oscillent entre 89,31 % à l’Ouest du verger et 92,4 % au Sud-ouest. En revanche, les intensités de mycorhization sont inférieures à 25 % dans l’ensemble du verger cacaoyer. Ces résultats indiquent que les systèmes agroforestiers à cacaoyer en Côte d’Ivoire abritent une grande diversité de CMA qui pourrait être utilisé dans divers initiatives biotechnologique en agriculture durable.  Arbuscular mycorrhizal fungi live in symbiosis with plant roots, helping them to absorb the nutrients they need for growth and development. In Côte d'Ivoire, this symbiosis is not considered in cocoa-based agroforestry strategies. The aim of this work is to study the mycorrhizal fungi associated with cocoa trees in agroforestry systems. To this end, cocoa spores and roots from 32 cocoa plantations located in the 4 main agro-ecological zones for cocoa production in Côte d'Ivoire were analysed. The diversity, spore density, mycorrhization rates, species richness and Shannon-Wiener diversity indices of CMA communities were determined. A study of the specific richness and relative abundance of 3271 CMA spores revealed 72 CMA morphotypes in the rhizosphere of cocoa trees in Côte d'Ivoire. On all the sites, 10 families, 17 genera and 49 species of CMA were recorded. Claroideoglomus etunicatum is the dominant species in the cocoa orchard. The abundance of spores in the Ivorian cocoa orchard varied between 7,89 and 17,84 spores.g-1 of soil, with an average of 13,42 spores.g-1 of soil. The number of spores was statistically the same across the ZAEs. Cocoa mycorrhization frequencies were generally high, ranging from 89,31% in the west of the orchard to 92,4% in the south-west. In contrast, mycorrhization intensities were below 25% throughout the cocoa orchard. These results indicate that cocoa agroforestry systems in Côte d'Ivoire harbour a wide diversity of CMAs that could be used in various biotecnological initiatives in sustainable agriculture

Selective Electrooxidation of Glycerol Into Value-Added Chemicals: A Short Overview

A comprehensive overview of the catalysts developed for the electrooxidation of glycerol with the aim of producing selectively value-added compounds is proposed in the present contribution. By presenting the main results reported in the literature on glycerol electrooxidation in acidic and alkaline media, using different kinds of catalytic materials (monometallic catalysts based on platinum group metals and non-noble metals, multimetallic alloys, or modification of surfaces by adatoms, etc.) and under different experimental conditions, some general trends concerning the effects of catalyst composition and structure, of reaction medium and of the electrode potential to enhance the activity for the glycerol oxidation reaction and of the selectivity toward a unique value-added product will be presented and discussed. The objective is to provide a guideline for the development of electrochemical systems which allow performing the electrooxidation of glycerol at the rate and selectivity as high as possible

Diversité des Champignons Mycorhiziens à Arbuscule Associés aux Cacaoyers (Theobroma cacao L.) en Côte d’Ivoire

Les champignons mycorhiziens à arbuscule vivent en symbiose avec les racines des plantes aidant celles-ci à absorber les nutriments nécessaires à leur croissance et développement. En Côte d’Ivoire, cette symbiose n’est pas prise en compte dans les stratégies agroforestières à base de cacaoyer. Ce travail vise à étudier les mycorhizes associés aux cacaoyers dans les systèmes agroforestiers. Les spores et les racines de cacaoyer issus de 32 plantations de cacao localisées dans les 4 principales zones agro-écologiques de production du cacao en Côte d’ Ivoire ont été analysées. La diversité, la densité des spores, les taux de mycorhization et la richesse spécifique des mycorhizes ont été déterminés. L’examen des spores met en évidence 72 morphotypes appartenant à 10 familles, 17 genres et 49 espèces de mycorhize. Claroideoglomus etunicatum est l’espèce dominante du verger cacaoyer. L’abondance des spores varie entre 10,53 à 31,24 spores.g-1 de sol pour une moyenne de 18,30 spores.g-1 de sol. Le nombre des spores est statistiquement le même à l’échelle des zone agroécologique. Les fréquences de mycorhization des cacaoyers sont généralement élevées et oscillent entre 89,31 % à l’Ouest du pays  et 92,4 % au Sud-ouest. En revanche, les intensités de mycorhization sont inférieures à 25 % dans l’ensemble du verger cacaoyer. Ces résultats indiquent que les systèmes agroforestiers à cacaoyer en Côte d’Ivoire abritent une grande diversité de champignons mycorhiziens à arbuscule qui pourrait être utilisée dans diverses initiatives biotechnologiques en agriculture durable.     Arbuscular mycorrhizal fungi (AMF) live in symbiosis with plant roots, helping them to absorb the nutrients they need for growth and development. In Côte d'Ivoire, this symbiosis is not considered in cocoa-based agroforestry strategies. The aim of this work is to study the mycorrhizal fungi associated with cocoa trees in agroforestry systems. To this end, cocoa spores and roots from 32 cocoa plantations located in the 4 main agro-ecological zones for cocoa production in Côte d'Ivoire were analysed. The diversity, spore density, mycorrhization rates, species richness and Shannon-Wiener diversity indices of arbuscular mycorrhizal fungi communities were determined. A study of the specific richness and relative abundance of 3271 spores revealed 72 arbuscular mycorrhizal fungi morphotypes in the rhizosphere of cocoa trees in Côte d'Ivoire. On all the sites, 10 families, 17 genera and 49 species of arbuscular mycorrhizal fungi were recorded. Claroideoglomus etunicatum is the dominant species in the cocoa orchard. The abundance of spores in the Ivorian cocoa orchard varied between 7,89 and 17,84 spores. g-1 of soil, with an average of 13,42 spores.g-1 of soil. The number of spores was statistically the same across the agroecological zones. Cocoa mycorrhization frequencies were generally high, ranging from 89,31% in the west of the orchard to 92,4% in the south-west. In contrast, mycorrhization intensities were below 25% throughout the cocoa orchard. These results indicate that cocoa agroforestry systems in Côte d'Ivoire harbour a wide diversity of AMF that could be used in various biotecnological initiatives in sustainable agriculture

Impact of Dietary Diversification on the Prognostic Inflammatory and Nutritional Index in School-Age Children in the Nawa Region (Côte d’Ivoire)

The objective of this work was to study the impact of food diversification based on sweet potato, soybean, and cowpea on the prognostic inflammatory and nutritional index (PINI) in school-aged children in the Nawa region. This study took place from October 2017 to May 2018 among 240 pupils aged 6 to 12, divided into four groups of 60. Four types of meals were proposed: rice with tomato soup and fish (group 1), sweet potato porridge enriched with green soybeans (group 2), sweet potato porridge enriched with white cowpea (group 3), or sweet potato porridge accompanied by white cowpea with green soybeans (group 4). There were three blood samples: before eating meals (phase 0), the end of the first trimester (phase 1), and the end of the second trimester (phase 2). Blood assay for C-reactive protein (CRP), orosomucoid, albumin, and prealbumin was performed using COBAS c311 analyzer. PINI was calculated. Groups 3 and 4 showed a slight increase in albumin values (42.24 ± 0.95 g/L and 41.51 ± 1.71 g/L, respectively) compared to group 1. CRP decreased from phase 1 for group 1 (2.06 ± 0.26 mg/L) and group 4 (2.38 ± 0.36 mg/L). Orosomucoid increased insignificantly (p > 0.05) in group 3 (0.74 ± 0.04 g/L) and group 4 (0.71 ± 0.04 g/L). PINI was reduced by 0.37 (group 1), 0.36 (group 2), 0.46 (group 3) and 0.44 (group 4). Food diversification based on sweet potato and white cowpea has a positive impact on PINI in more than 80% of pupils

Dynamic Changes in Volatile Organic Compounds During the Spoilage of Palm Wine Stored at Ambient Temperature

This study aimed to investigate the volatile organic compounds (VOCs) variations during the spoilage of palm wine stored at ambient temperature and identify potential shelf-life markers. Palm wine collected from local tappers and resellers were stored at ambient temperature (28-30°C) for 96 h. At an interval of 24 h, VOCs variations were investigated using Solid phase Microextraction-Gas Chromatography-Mass Spectroscopy (SPME-GC/MS) method. Changes in sensory quality and potential flavour contributors were also explored. The sensory rejection time was found at 24 h and 48 h of storage for palm wines collected from the tappers and resellers, respectively. The first attribute to be spoiled was taste followed by odour and appearance. A total of 23 VOCs distributed in six chemical families were identified. Alteration of palm wine sample is characterised by an increase in concentration of alcohol (isoamyl alcohol, isobutanol and 1-octanol), aceti acid and acetoin, and a decrease in ester concentration (ethyl acetate and ethyl hexanoate). In the view to fight against the short shelf-life and develop new preservation methods, these compounds can be used as markers of spoiled palm wine

Quantitative estimates of glacial refugia for chimpanzees (Pan troglodytes) since the Last Interglacial (120,000 BP).

Paleoclimate reconstructions have enhanced our understanding of how past climates have shaped present-day biodiversity. We hypothesize that the geographic extent of Pleistocene forest refugia and suitable habitat fluctuated significantly in time during the late Quaternary for chimpanzees (Pan troglodytes). Using bioclimatic variables representing monthly temperature and precipitation estimates, past human population density data, and an extensive database of georeferenced presence points, we built a model of changing habitat suitability for chimpanzees at fine spatio-temporal scales dating back to the Last Interglacial (120,000 BP). Our models cover a spatial resolution of 0.0467° (approximately 5.19 km2 grid cells) and a temporal resolution of between 1000 and 4000 years. Using our model, we mapped habitat stability over time using three approaches, comparing our modeled stability estimates to existing knowledge of Afrotropical refugia, as well as contemporary patterns of major keystone tropical food resources used by chimpanzees, figs (Moraceae), and palms (Arecacae). Results show habitat stability congruent with known glacial refugia across Africa, suggesting their extents may have been underestimated for chimpanzees, with potentially up to approximately 60,000 km2 of previously unrecognized glacial refugia. The refugia we highlight coincide with higher species richness for figs and palms. Our results provide spatio-temporally explicit insights into the role of refugia across the chimpanzee range, forming the empirical foundation for developing and testing hypotheses about behavioral, ecological, and genetic diversity with additional data. This methodology can be applied to other species and geographic areas when sufficient data are available