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Background: Mescal production is the main economic activity associated to agaves in Mexico, which involves 53 species mostly harvested from forests. The increasing mescal demand has influenced risk in both agave populations and mescal production, but other social and ecological factors also intervene. We hypothesized that the greater the risk the greater the complexity of management responses; otherwise, the greater the probability of populations' depletion. We analysed this hypothesis by examining the diversity of risk conditions and management practices of Agave inaequidens in the state of Michoacán, in central-western Mexico., Methods: We studied five communities of Michoacán, documenting through 41 semi-structured interviews the use forms, risk perception, number of agaves annually extracted, and the management practices. Using a matrix with social-ecological and technological data analyzed by PCA, we evaluated similarities of management contexts. A data matrix with information on risk of agave populations, and other about management practices were analysed also through CCA and PCA. The scores of the first principal components were considered as indexes of risk and management complexity, respectively. A regression analysis of these indexes evaluated their relation., Results: We recorded 34 different uses of A. inaequidens, the most important being mescal production (mentioned by 76.1 % of people interviewed). Nearly 12.5 % of people practice only gathering, but others mentioned the following practices: Selective let standing of agaves for seed production (20 %); in situ transplanting of saplings; seed propagation in nurseries and saplings transplanting to forest (10 %); suckers transplanting (7.5 %); seed dispersal in forests; banning (5 %); enhancing of agave growth by removing tree canopies (2.5 %); transplanting from the wild to live fences (45 %); intensive plantations (35 %). The highest vulnerability of agave populations was identified in communities where risk is not counteracted by management. In two communities we identified the highest risk (annual extraction from 4,353 to 6,557 agaves), but different actions counteracting such risk., Conclusions: Interchange of knowledge and management experiences developed by handlers is crucial for the regional conservation, recovering, and sustainable management of A. inaequidens populations.

Background: Agave inaequidens and A. hookeri are anciently used species for producing the fermented beverage 'pulque', food and fiber in central Mexico. A. inaequidens is wild and cultivated and A. hookeri only cultivated, A. inaequidens being its putative wild relative. We analysed purposes and mechanisms of artificial selection and phenotypic divergences between wild and managed populations of A. inaequidens and between them and A. hookeri, hypothesizing phenotypic divergence between wild and domesticated populations of A. inaequidens in characters associated to domestication, and that A. hookeri would be phenotypically similar to cultivated A. inaequidens., Methods: We studied five wild and five cultivated populations of A. inaequidens, and three cultivated populations of A. hookeri. We interviewed agave managers documenting mechanisms of artificial selection, and measured 25 morphological characters. Morphological similarity and differentiation among plants and populations were analysed through multivariate methods and ANOVAs., Results: People recognized 2-8 variants of A. inaequidens; for cultivation they select young plants collected in wild areas recognized as producing the best quality mescal agaves. Also, they collect seeds of the largest and most vigorous plants, sowing seeds in plant beds and then transplanting the most vigorous plantlets into plantations. Multivariate methods classified separately the wild and cultivated populations of A. inaequidens and these from A. hookeri, mainly because of characters related with plant and teeth size. The cultivated plants of A. inaequidens are significantly bigger with larger teeth than wild plants. A. hookeri are also significatly bigger plants with larger leaves but lower teeth density and size than A. inaequidens. Some cultivated plants of A. inaequidens were classified as A. hookeri, and nearly 10% of A. hookeri as cultivated A. inaequidens. Wild and cultivated populations of A. inaequidens differed in 13 characters, whereas A. hookeri differed in 23 characters with wild populations and only in 6 characters with cultivated populations of A. inaequidens., Conclusions: Divergence between wild and cultivated populations of A. inaequidens reflect artificial selection. A. hookeri is similar to the cultivated A. inaequidens, which supports the hypothesis that A. hookeri could be the extreme of a domestication gradient of a species complex.