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Cercosporoid fungi (Mycosphaerellaceae, Mycosphaerellales, Ascomycota) are one of the largest and most diverse groups of hyphomycetes causing a wide range of diseases of economically important plants as well as of plants in the wild. Although more than 6000 species are known for this group, the documentation of this fungal group is far from complete. Especially in the tropics, the diversity of cercosporoid fungi is poorly known. The present study aims to identify and characterise cercosporoid fungi collected on host plants belonging to Fabaceae in Benin, West Africa. Information on their morphology, host species and DNA sequence data (18S rDNA, 28S rDNA, ITS and tef1) is provided. DNA sequence data were obtained by a simple and non-culture-based method for DNA isolation which has been applied for cercosporoid fungi for the first time in the context of the present study. Among the loci used for the phylogenetic analysis, tef1 provided the best resolution together with the multigene dataset. Species delimitation in many cases, however, was only possible by combining molecular sequence data with morphological characteristics. Based on forty specimens recently collected in Benin, 18 species are presented with morphological descriptions, illustrations and sequence data. Among these, six species in the genus Cercospora and two species in Pseudocercospora are proposed as species new to science. The newly described species are Cercospora (C.) beninensis on Crotalaria macrocalyx, C. parakouensis on Desmodium tortuosum, C. rhynchophora on Vigna unguiculata, C. vignae-subterraneae on Vigna subterranea, C. tentaculifera on Vigna unguiculata, C. zorniicola on Zornia glochidiata, Pseudocercospora sennicola on Senna occidentalis and Pseudocercospora tabei on Vigna unguiculata. Eight species of cercosporoid fungi are reported for Benin for the first time, three of them, namely C. cf. canscorina, C. cf. fagopyri and C. phaseoli-lunati are new for West Africa. The presence of two species of cercosporoid fungi on Fabaceae previously reported from Benin, namely Nothopassalora personata and Passalora arachidicola, is confirmed.
Ipomoea beninensis Akoègn., Lisowski & Sinsin (Convolvulaceae) is the only endemic plant known for Benin. To date, no data exist on its usages, distribution, abundance, and threats. An improved understanding of indigenous know- ledge and of local practices can provide insight into how the species could be sustainably conserved. We interviewed 114 local residents for collecting ethnobotanical and ethnoecological data in six sites known to host the species. Data were pro- cessed by calculation of descriptive statistics and variance and multivariate analyses. A total of twelve uses were reported. Among them, treatment of varicella (19%), malaria (18%) and fodder (17%) were the most recurrent. These mainly involve use of the species rootstock. Almost all respondents mentioned decline of the species in natural habitats. None of them was aware about the endemic status of the species. Consequently, negative practices toward the protection of I. beninensis were prevalent among local residents. Several conservation measures are proposed to ensure the longterm survival of I. beninensis.
In West African savannas, human land use affects the density of woody species seedlings and saplings (juveniles) by altering the state of the physical, chemical, and biological characteristics of the land resulting in different land-cover types. We determined juvenile densities of 25 characteristic woody savanna species on non-arable sites, in fallows and in a protected area (in total 39 plots), and analyzed the influence of land use on juvenile densities. We further related the influence of land use on juvenile densities to 23 environmental parameters describing soil properties and vegetation structure. Soil acidity, particle size distribution of the soil, and vegetation structure differed between land-cover types. In terms of human impact, we detected five groups of species responding similarly to land use. Although we detected significant differences in soil properties, their direct effects on juvenile densities are less pronounced than their indirect effects. By altering the availability of resources, soil properties affect height and cover of all plants growing in the surrounding of a young woody plant, increasing the competition for light, water and nutrients during the establishment and initial growth. These effects are intensified by human land use and vary between land-cover types.
The globalized Western culture of innovation, as propagated by major aid institutions, does not necessarily lead to empowerment or improvement of the well-being of the stakeholders. On the contrary, it often blocks viable indigenous innovation cultures. In African societies and African Diasporas in Latin America, cultures of innovation largely accrue from the informal, not the formal sector. Crucial for their proper understanding is a threefold structural differentiation: between the formal and informal sector, within the informal sector, according to class, gender or religion, and between different transnational social spaces. Different innovation cultures may be complementary, mutually reinforcing, or conflicting, leading in extreme cases even to a ‘clash of cultures’ at the local level. The repercussions of competing, even antagonistic agencies of innovative strategic groups are demonstrated, analyzing the case of the African poor in Benin and the African Diasporas of Brazil and Haiti.