Background: Traditional medicine remains the only health care available in many rural areas in Madagascar like the rural community of Ambalabe, located in a very remote area in the eastern part of the country. With limited access to modern medicine, the local population uses medicinal plants to treat most diseases. In this study, we aimed to inventory medicinal plants used by local people and how those relate to the treatment of the most frequent diseases encountered in Ambalabe. Methods: We interviewed participants in order to identify the most frequent diseases in the region and the medicinal plants used to treat them. The local physician was asked about the most frequent diseases, and ethnobotanical surveys to record medicinal plants and their uses, using semi-structured interviews and free listing, were conducted among 193 informants in local villages, of which 54 % were men and 46 % were women, ageing from 16 to 86 years. The local names, the uses of each plant species and the way they are prepared and administered were recorded and accompanied by herbarium specimens for identification. We also interviewed four traditional healers to elicit more details on the preparation and the use of plants. Results: Our research allowed us to identify six most frequent diseases, namely diarrhea, malaria, stomach-ache, cough, bilharzia and dysentery. Among 209 plant species identified as having medicinal use, 83 species belonging to 49 families and 77 genera were used to treat these diseases. Our analyses highlighted the 11 commonly used species for their treatment, and also 16 species with a high fidelity level (FL ≥ 75 %) for each ailment. Diarrhea is one of the diseases with high number of species recorded. Conclusions: This study highlighted the closed relationship between people in Ambalabe and plant species, especially when faced with frequent diseases. However, most of the species used were collected in the surroundings of the villages. Few species were from Vohibe forest in which a management system on the use of plant species was already established. Therefore, a sustainable use management should be considered for wild species from which medicinal plants are highly abundant.

This study focuses on the large outdoor markets of the capital of Madagascar, Antananarivo. As the largest metropolitan area in Madagascar with a population of nearly two million, the region has great capacity for consumption of medicinal plant remedies despite numerous pharmacies. Medicinal plant use spans all socioeconomic levels, and the diverse metropolitan population allows us to study a wide variety of people who consume these plants for medical purposes. The purpose of this study is to identify and generate a list of medicinal plants sold in the traditional markets with a focus on those collected in the forests around Antananarivo, get an idea of the quantities of medicinal plants sold in the markets around Antananarivo, and assess the economy of the medicinal plant markets. In order to determine which medicinal plants are most consumed in Antananarivo, ethnobotanical enquiries were conducted in the five main markets of the capital city. Ethnobotanical surveys were conducted with medicinal plant traders, suppliers, harvesters and cultivators, with voucher specimens created from the plants discussed. Trade circuit information was established and the income generated by the trade of some of the species was assessed. The inventory of the Antananarivo markets resulted in a list of 89 commercialized plant species. Ten of the 89 were mentioned by 60-100 % of vendors. Profitability for vendors is high and competitive with other salaried positions within Antananarivo. Transportation costs are also high and therefore lower profitability for other members in the supply chain. The markets of Antananarivo have always played a vital cultural role in the lives of urban Malagasy, but our study shows they also play an economic role not only for urban residents but rural harvesters as well. Continued research and monitoring of the non-timber forest products trade in Antananarivo is needed to better understand the impact of trade on the wild plant populations.

Rural households in the Mahafaly region of semi-arid SW-Madagascar strongly depend on the exploitation of natural resources for their basic needs and income regeneration. An overuse of such resources threatens the natural environment and people’s livelihood. Our study focuses on the diversity and use of wild yams and medicinal plants. We hypothesized that knowledge on the use of these resources highly depends on farmers’ socio-economic household characteristics. To test this hypothesis, an ethnobotanical survey was conducted based on semi-structured interviews recording socio-economic base data and information on local knowledge of medicinal and wild yam species. This was followed by field inventories compiling plant material for botanical identification. Six species of wild yam and a total of 214 medicinal plants from 68 families and 163 genera were identified. Cluster and discriminant analysis yielded two groups of households with different wealth status characterized by differences in livestock numbers, off-farm activities, agricultural land and harvests. A generalized linear model highlighted that economic factors significantly affect the collection of wild yams, whereas the use of medicinal plants depends to a higher degree on socio-cultural factors. Wild yams play an important role in local food security in the Mahafaly region, especially for poor farmers, and medicinal plants are a primary source of health care for the majority of local people. Our results indicate the influence of socio-economic household characteristics on the use of forest products and its intensity, which should be considered in future management plans for local and regional forest conservation.

The ecology of Madagascar's grasslands is under-investigated and the dearth of ecological understanding of how disturbance by fire and grazing shapes these grasslands stems from a perception that disturbance shaped Malagasy grasslands only after human arrival. However, worldwide, fire and grazing shape tropical grasslands over ecological and evolutionary timescales, and it is curious Madagascar should be a global anomaly. We examined the functional and community ecology of Madagascar's grasslands across 71 communities in the Central Highlands. Combining multivariate abundance models of community composition and clustering of grass functional traits, we identified distinct grass assemblages each shaped by fire or grazing. The fire-maintained assemblage is primarily composed of tall caespitose species with narrow leaves and low bulk density. By contrast, the grazer-maintained assemblage is characterized by mat-forming, high bulk density grasses with wide leaves. Within each assemblage, levels of endemism, diversity and grass ages support these as ancient assemblages. Grazer-dependent grasses can only have co-evolved with a now-extinct megafauna. Ironically, the human introduction of cattle probably introduced a megafaunal substitute facilitating modern day persistence of a grazer-maintained grass assemblage in an otherwise defaunated landscape, where these landscapes now support the livelihoods of millions of people.

This paper reports a study undertaken in three remote communities (Mahaboboka, Amboronabo, Mikoboka), located in Sakaraha, Southwestern Madagascar. Not only villages are far away from sanitary infrastructures and doctors but drugs and consulting fees are unaffordable to villagers. They rely essentially on natural resources for health care as for most of rural areas in Madagascar. This paper aims to document medicinal plants used by communities in Sakaraha and to present the most important plant species used in traditional medicine. Semi – structured interview was conducted within 214 informants in 34 villages of the study area. Different ailments encountered in the site study were classified in various categories. For data analysis, frequency of citation (Fq), Informant Consensus Factor (Fic), Fidelity Level (FL) and Use Value (UV) were assessed to find agreement among informants about the use of plants as remedies. Mann-Whitney, Kruskall-Wallis and Spearman correlation tests were performed to determine use of medicinal plants following social status of informants. A total of 235 medicinal plant species belonging to 198 genera and 75 families were inventoried. The richest families in species used for medicinal purposes were: Fabaceae, Apocynaceae, Rubiaceae, Euphorbiaceae, Asteraceae, and Poaceae. Plant species cited by informants were used to treat 76 various ailments classified in 13 categories. Leaves and leafy twigs were the most used plant parts and decoction was the mostly cited way of preparation of these medicinal plants species. In average, local people cited 6.7 ± 6.03 medicinal taxa among them, Cedrelopsis grevei is the most cited medicinal plants (Fq. 0.28). With Cedrelopsis grevei (UV = 0.48), Henonia scoparia (UV = 0.43) are mostly used species. Leonotis nepetifolia (FL = 96%) and Strychnos henningsii (FL = 92%) are plant species claimed by high percentage of informants to treat the Digestive System Disorder. This study highlighted that medicinal plants used by people from three communities in the Southwestern Madagascar are diverse. These plants species ensure care to all family members including babies, children, mothers and adult people. Through this study, newly reported medicinal plants were identified for further work.

The pantropical genus Vanilla is a member of the Orchidaceae family, one of the largest and most diverse families of angiosperms in the world. It originated in America and differentiated in America, Africa, and Asia. About 132 species of Vanilla have now been accepted since the discovery of the genus. Within the Vanilla genus, leaflessness has appeared at least three independent times, in Africa, Asia, and America as an adaptation to drought conditions. The South-West Indian Ocean (SWIO) region, a biodiversity hotspot for orchids, is home to seven leafless species. Chloroplast markers failed to differentiate species within this recent SWIO clade. Morphological traits used for description are very similar between species and do not provide reliable identification. Moreover, some of the species have overlapping flowering periods and geographic distribution in Madagascar, increasing the probability of finding some sympatric species and, therefore, hybrids. Leafless Vanilla species from the SWIO islands are thus an excellent model for understanding the evolution of orchids. For their conservation, and to confirm the identity of these leafless species, an integrated approach with classical taxonomy using a large number of samples, intense fieldwork on biology and ecology, and molecular studies using variable markers is necessary.