Révision du genre Digitaria Haller (Poaceae) au Sénégal : proposition d’une clé de détermination pour une meilleure identification des espèces

Le genre Digitaria Haller (Poaceae) constitue l’un des genres les plus diversifiés des Poaceae du Sénégal avec 19 espèces. Bien qu’il y ait une monographie mondiale du genre, la détermination des espèces reste difficile et repose essentiellement sur les caractères de l’appareil reproducteur. Ce travail, qui est une révision du genre Digitaria au Sénégal, est entrepris afin de rechercher des caractères pertinents sur l’appareil végétatif et d’améliorer l’identification des espèces. Pour ce faire, une description détaillée des différents organes des spécimens étudiés est réalisée à l’aide d’une loupe binoculaire. Les résultats de l’étude montrent que la pubescence de l’épillet est un caractère essentiel pour l’identification des espèces. De plus, les longueurs relatives de la glume supérieure et de la lemma inférieure sont très intéressantes pour la discrimination d’espèces affines. Toutefois, l’étude supplémentaire des organes végétatifs de la plante adulte montre que certains caractères végétatifs pourraient contribuer considérablement à l’amélioration de l’identification des espèces. Il s’agit du cycle biologique, de la pubescence de la ligule, de la marge du limbe, des noeuds et des entre-noeuds du chaume qui sont des caractères plus faciles à observer. Une clé de détermination basée sur des caractères végétatifs et reproducteurs des espèces est ainsi élaborée.© 2015 International Formulae Group. All rights reserved.Mots clés: Digitaria, Poaceae, révision, clé de détermination, SénégalEnglish Title: Review of Digitaria Haller (Poaceae) genus in Senegal: suggestion of a determination key for a better identification of speciesEnglish AbstractThe genus Digitaria Haller (Poaceae) is one of the most diversified genera of Poaceae in Senegal with 19 species. Although it has a worldwide monograph of the genus, the identification of species remains difficult and mainly based on the characteristics of the reproductive system. This work, which is a review of the genus  Digitaria in Senegal, is undertaken in order to search relevant characteristics on the vegetative system and to improve the identification of species. To do this, a detailed description of the various organs of the studied specimens is carried out using a binocular microscope. The results of the study show that the pubescence of the spikelet is an essential characteristic for the identification of species. Moreover, the relative lengths of the upper glume and lower lemma are very interesting for the discrimination of species closely related. However, the additional study of vegetative organs of the adult plant shows that some vegetative characteristics could contribute considerably to the improvement of the identification of species. It is the biological cycle, the pubescence of the ligule, the margin of the leaf blade, nodes and internodes of the thatch which are characteristics easier to observe. A key of determination based on vegetative and reproductive characteristics of species is thus worked out.© 2015 International Formulae Group. All rights reserved.Mots clés: Digitaria, Poaceae, review, key of determination, Senega

Village Baseline Study: Site Analysis Report for Kaffrine – Kaffrine, Senegal

The village baseline study of Toune Mosquée village in the CCAFS benchmark site Kaffrine in Senegal took place from June 2 to 4, 2011. Natural resources in the village are in a progressive state of degradation. The ‘protected’ forest has almost disappeared, the soils have low fertility and are degraded, and crop production is not sufficient to meet the food needs of a family throughout the year. Families must buy food to fill the gap in production. For that they harvest and sell forest products, which creates a vicious cycle of resource degradation. The male and female groups identified 35 organisations operating in the village including informal groups, state services, associations, NGOs and Muslim brotherhoods. While 18 of those work on food security issues, only 4 are involved in the management and protection of natural resources. Very few agricultural extension and training opportunities target women despite the women’s significant role in agriculture and livestock production. Women obtain information on livestock feeding techniques from people and organisations such as the horticultural project, women’s associations, and water and forest services. Men get information on soil inputs and soil fertility management from other farmers, organisations, radio and television, and from community leaders, notably the office of the village chief and the mosque on Fridays. The radio is the form of media most commonly used by the women but few women own a radio

Adaptation Actions in Africa: Evidence that Gender Matters

This paper presents the initial data analyses of the CCAFS gender survey implemented in four sites in Africa. Using descriptive statistics we show gender differences in terms of perceptions of climate change, awareness and adoption of climate smart agricultural (CSA) practices, and types and sources of agro-climatic information in the four sites.We find that both men and women are experiencing changes in long-run weather patterns and that they are changing their behaviours in response; albeit relatively minor shifts in existing agricultural practices. For example, the most prevalent changes reported include switching crop varieties, switching types of crops and changing planting dates. As expected, women are less aware of many CSA practices. Encouragingly, this same pattern does not hold when it comes to adoption; in many cases, in East Africa in particular, women, when aware, are more likely than or just as likely as men to adopt CSA practices. In West Africa, overall, the adoption of these practices was much lower. In addition, we see that access to information from different sources varies greatly between men and women and among the sites; however, promisingly, those with access to information report using it to make changes to their agricultural practices. Our findings suggest that targeting women with climate and agricultural information is likely to result in uptake of new agricultural practices for adaptation

Chapitre 8. Dynamique de stockage du carbone dans les sols du Sénégal

Introduction Au Sénégal, la dynamique de stockage du carbone dans les sols est souvent estimée par des approches de modélisation (Tschakert et al., 2004 ; Parton et al., 2004 ; Woomer et al., 2004 ; Lufafa et al., 2008 ; Stoorvogel et al., 2009 ; Dièye et al., 2012 ; Touré et al., 2013 ; Loum et al., 2014). Quelques études expérimentales ont également été réalisées (Elberling et al., 2003 ; Manlay et al., 2002 ; Masse et al., 2004). La teneur des sols en carbone est généralement faible, de mo..

Case study of Daga-Birame CSV for CCAFS ISP11/6.1.2 – Senegal

Senegal, with 196,712 km2 land area, is located at the extreme west of the African continent (Longitudes 11°21W - 17°32N and Latitudes 12°8N - 16°41N). The country’s soils are in general of low fertility, fragile and very susceptible to wind and water erosion. The climate is of Sudano-Sahelian type characterized by alternating dry season (November to May) and rainy season (June to October). The 700 km coastline brings climatic differences between coastal areas and inland zones. Rainfall amount follows a latitudinal variation going from 300 mm in the north semi-desertic areas to 1200 mm in the south. Senegal is divided into 7 agro-ecological zones for management perspectives: River Valley, Niayes, Groundnut Basin (North and South), Silvo-Pastoral zone, Eastern Senegal and Upper Casamance, Lower Casamance (CIAT-BFS/USAID, 2016). The country’s economy is mainly driven by crop and livestock production contributing 17% of the GDP and employing about 70% of the population (NAPA, Republic of Senegal 2006). Like other sub-Saharan African countries, Senegal faces food insecurity as a consequence of climate variability and change combined with other global changes (Zougmoré et al., 2015)