Rafael Lira

Biological diversity in the Tehuacán-Cuicatlán Valley, Mexico

A general overview of the biological knowledge of the floristic province of the Tehuacán-Cuicatlán Valley in central-southern Mexico is presented. Floristic and faunistic richness and endemism, as well as uses of the flora are analyzed and discussed for this area, recently declared a biosphere reserve. The analysis shows that, in approximately 10 000 km2 the Tehuacán-Cuicatlán Valley contains between 10 and 11.4% of the Mexican flora. In addition, the valley possesses 365 endemic species that represent 13.9% of its flora. With respect to the fauna diversity, the available information is less comprehensive than for plants. Nevertheless, the study shows that the 11 species of amphibians, 48 species of reptiles, and 91 species of birds recorded for the valley surpasses the diversity found in other dry-lands of the world. In relationship to the mammals of the region, the available data are poor for most of the groups except for bats, for which 24 species have been reported. Regarding the use of the flora, the analysis revealed that 815 species are utilized by the people in the valley. A discussion related to future research activities is also included.

Plant resources of the Tehuacán-Cuicatlán valley, Mexico

Information on richness of plant resources, and their forms of use and management in the biosphere reserve Tehuacan-Cuicatlan, Mexico is analyzed. This 10 000 km2 region hosts nearly 2700 vascular plant species, and it is acknowledged as one of the arid areas with the highest floristic diversity in North America. The seven indigenous ethnic groups that live in this region have cultural roots that date back almost 10 000 years. Based upon ethnobotanical and floristic studies, as well as bibliographical sources, a total of 808 useful plant species were identified, most of them (90%) being native, and 44 species being endemic to the region. A total of 681 species are wild plants, 109 are weeds and ruderal plants, and 86 are domesticated crops. However, it was noted that considerable overlap exists between the species of these 3 categories. For example, while wild and ruderal plants (706 species) are foraged by both humans and domestic animals, 59 species of this group are also managed in situ. On the other hand, 168 wild, ruderal and domesticated species are cultivated. The Tehuacán-Cuicatlan Valley is one of the richest regions of Mexico in plant resources. Local knowledge on use and management of plants is a valuable source of information for designing conservation and social development strategies for the biosphere reserve.ResumenSe analiza informatión sobre la riqueza de recursos vegetales, así como sus formas de uso y manejo en la reserva de la biosfera Tehuacán-Cuicatlán, México. Esta región, con una extensión de 10 000 km2, alberga a cerca de 2700 especies de plantas vasculares y es reconocida como una de las zonas áridas con mayor diversidad florística de Norteamerica. Incluye además a siete grupos étnicos indigenas con una historia cultural iniciada hace aproximadamente 10 000 años. Con base en estudios etnobotánicos y floristicos, así como informatión bibliográfica, se identificaron un total de 808 especies de plantas útiles, la mayor pane de las cuales (90%) son nativas y 44 son endémicas para la region. Un total de 681 especies son silvestres, 109 son arvenses y ruderales, y 86 son domesticadas, con algunas especies presentando al mismo tiempo conditión de silvestres, arvenses y domesticadas. En total, 706 especies de plantas silvestres, arvenses y ruderales son forrajeadas tanto por humanos como por animales domésticos en las áreas donde se encuentran, pero 59 de ellas son también manejadas in situ, mientras que 168 especies silvestres, arvenses y ruderales, asi como domesticadas, son cultivadas. El Valle de Tehuacán es una de las regiones de Mexico con mayor diversidad de recursos vegetales. El conocimiento indígena sobre uso y manejo de las plantas locales es una fuente de informatión valiosa para el diseño de estrategias de conservatión y desarrollo social para la reserva de la biosfera.

Ethnobotany and antibacterial activity of some plants used in traditional medicine of Zapotitlán de las Salinas, Puebla (México).

The village of Zapotitlán de las Salinas is situated in the Valley of Tehuacán-Cuicatlán, Puebla, Mexico. Plant species used by the local inhabitants to treat gastrointestinal diseases were identified using ethnobotanical, ethnographic and taxonomic methods. Out of 119 interviews, 44 plant species were registered, of which the following are the most frequently used (listed in descending order): Lippia graveolens H.B. et K. (Verbenaceae), Lantana achyranthifolia Desf. (Verbenaceae), Turnera diffusa (Willd.) ex Schult. (Turneraceae), Lippia oaxacana Rob. et Greenm. (Verbenaceae), Gymnolaena oaxacana (Greenm.) Rydb. (Asteraceae), Cordia curassavica (Jacq.) Roem. et Schult. (Boraginaceae), Lantana camara L. (Verbenaceae) and Acalypha hederacea Torrey (Euphorbiaceae). From these plants, hexane, chloroform and ethanol extracts were prepared in order to assess their antibacterial activity against 14 bacterial strains causing the most common gastrointestinal diseases in Mexican population. All hexane extracts showed antibacterial activity against Gram-positive and Gram-negative bacteria. There is a correlation between the frequency of mention (of plant use) and the antibacterial activity. In conclusion, the knowledge of plants most frequently used for gastrointestinal infections in Zapotitlán de las Salinas is supported by scientific rationale.

Plant Management in the Tehuacán-Cuicatlán Valley, Mexico1

Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently practiced in the Tehuacán-Cuicatlán Valley, México, were documented and analyzed based on ethnobotanical studies conducted in 13 villages with six indigenous groups and Mestizo people. The information was organized in a data base, and then detailed and guided to a consensus through six workshops carried out by ethnobotanists working in the area. From a total of 1,608 useful plant species, we identified 610 with at least one management type other than simple gathering. Managed species are mainly used as food, fodder, medicinal, and ornamental, and they belong to 101 plant families. The higher species numbers were recorded in Cactaceae, Asteraceae, Fabaceae, Crassulaceae, and Agavaceae. Nearly 60% of the managed species are native to the region and the rest are introduced from other regions of Mexico and the world. In total, 400 species are ex situ managed out of their natural environments through seed sowing and/or planting their vegetative propagules or entire young plants; 373 species are in situ managed in their natural habitats as follows: all these species are deliberately left standing during vegetation clearance, 76 species are also enhanced intentionally favoring their abundance through modifications of their habitat, or directly by planting their propagules, and 51 receive protection through regulations, particular strategies of extraction, and actions against herbivores, competitors, freezing, radiation, and drought. Most management forms involve artificial selection at different intensity levels. The information allows visualizing co-occurrence of incipient and advanced forms of management at different intensity levels within and among species, which helps to postulate testable hypotheses on factors influencing plant management and domestication in an important area for studying the origins of agriculture.Manejo de plantas en el Valle de Tehuacán-Cuicatlán, México. Se documentaron los diferentes tipos de manejo de plantas que practican actualmente los pobladores del Valle de Tehuacán-Cuicatlán, México. El análisis se basa en estudios etnobotánicos llevados a cabo en 13 comunidades campesinas con seis grupos indígenas y poblados mestizos. La información se organizó en una base de datos, la cual posteriormente se detalló y se consensó a través de seis talleres en los que participaron los etnobotánicos trabajando en la región y cuyos trabajos son la base de esta investigación. De un total de 1,608 especies de plantas útiles, identificamos 610 con al menos un tipo de manejo distinto a la recolección simple. Las especies manejadas pertenecen a 101 familias botánicas y se utilizan principalmente como alimento, forraje, medicina y ornamentales. Los mayores números de especies manejadas se registraron entre las Cactaceae, Asteraceae, Fabaceae, Crassulaceae y Agavaceae. Aproximadamente 60% de las especies manejadas son nativas de la región y el resto son introducidas de otras regiones de México y del mundo. En total, 400 especies se manejan ex situ, fuera de sus ambientes naturales, mediante la siembra de sus semillas y la plantación de sus propágulos vegetativos o plantas juveniles; 373 especies se manejan in situ en sus hábitats naturales como sigue: todas estas especies se dejan en pie deliberadamente durante el aclareo de la vegetación; 76 especies son además promovidas intencionalmente, favoreciendo sus abundancias mediante modificaciones a sus hábitats o directamente plantando sus propágulos; y 51 especies reciben protección a través de reglas comunitarias, estrategias particulares de extracción y acciones contra herbívoros, competidores, heladas, radiación solar y sequías. La mayor parte de las formas de manejo involucran selección artificial a diferentes niveles de intensidad. La información permite visualizar la ocurrencia de formas de manejo incipientes y avanzadas a diferentes niveles de intensidad, simultáneamente dentro de una misma especie y entre especies. Esto permite postular hipótesis probables sobre los factores que influyen el manejo de plantas y su domesticación en una región importante para el estudio sobre el origen de la agricultura.

Traditional Knowledge and Useful Plant Richness in the Tehuacán-Cuicatlán Valley, Mexico

Traditional Knowledge and Useful Plant Richness in the Tehuacán–Cuicatlán Valley, Mexico. This study systematizes ethnobotanical information about the interactions between people and plants, ethnofloristic richness, the relative importance of useful species richness in relation to general species richness, and plant management in the Tehuacán–Cuicatlán Valley of central Mexico. The study recorded a total of 1,605 useful vascular plant species (61.2% of the total species richness of the regional vascular flora), this being the region with the highest absolute richness of useful plant species in Mexico. The null hypothesis that plant families with a higher number of useful species would be those having a higher general species richness was analyzed through residuals method. The plant families richest in useful species were Poaceae, Asteraceae, Cactaceae, Cyperaceae, Mimosaceae, and Solanaceae, most of which also have the highest general floristic richness. However, analyses of use categories did not generally corroborate our hypothesis. About 1,335 of the useful species are wild, more than 500 species are submitted to some type of management (62 species are tolerated, 34 protected, 50 enhanced, and 358 cultivated), but only a few have been studied to document their process of domestication. This information can be useful for developing regional strategies of sustainable management of plant resources.Conocimiento tradicional y riqueza de plantas útiles en el Valle de Tehuacán-Cuicatlán, MéxicoConocimiento tradicional y riqueza de plantas útiles en el Valle de Tehuacán-Cuicatlán, México. Este trabajo sistematiza información etnobotánica sobre las interacciones entre la gente y las plantas, la riqueza etnoflorística, la importancia relativa de las especies útiles con respecto a la riqueza florística general, y sobre el manejo de plantas en el Valle de Tehuacán–Cuicatlán, en el centro de México. Se registró un total de 1,605 especies de plantas vasculares útiles (61.2% de la riqueza total de la flora vascular de la región), lo que identifica a la región como la de mayor riqueza de plantas útiles de México en términos absolutos. Mediante el método de residuales se analizó la hipótesis nula de que las familias con mayor número de especies útiles serían las de mayor riqueza florística. Se encontró que las familias con mayor número de especies útiles fueron Poaceae, Asteraceae, Cactaceae, Cyperaceae, Mimosaceae, y Solanaceae, las cuales en su mayoría son las de mayor riqueza florística en la región. No obstante, al efectuar el análisis por categorías de uso no siempre se confirmó nuestra hipótesis. Casi 1,335 de las plantas útiles son silvestres, pero alrededor de 500 están sometidas a algún tipo de manejo (62 especies son toleradas, 34 protegidas, 50 fomentadas y 358 cultivadas), pero sólo para algunas de ellas se ha estudiado cómo operan los proceso de domesticación. La información generada en el trabajo puede ser útil para el desarrollo de estrategias regionales de manejo sustentable de los recursos vegetales.

A proposal for the conservation of the family Cucurbitaceae in Mexico

The pantropical Cucurbitaceae is one of the most important families ofvascular plants. The family includes 118 genera and 825 species, and Mexicois one of its most important centers of diversity, with 34 genera and 141species and subspecific taxa, including 13 cultivated ones. Five genera and 70taxa are endemic to the country. Some Mexican and Latin American wild speciesare close relatives of important crops, and others are employed as food ormedicine. Accordingly, in countries like Mexico the conservation of members ofthis family should be a priority. In this paper a list of members ofCucurbitaceae occurring in Mexico and their distribution patterns at state levelare discussed. Using cluster strategies, the states were classified according totheir floristic similarities. Hotspots of total diversity and endemismsat state level are identified, in order to discuss their role in futureconservation strategies. Iterative methods applied by conservation biology todetermine the best places for conservation are used to identify hierarchicallythe most important states that merit to be considered in this goal. Resultsindicate that implementing conservation strategies in half of the states wouldallow the protection of all the diversity found in the country, especially theendemisms. The combination of the results provided by the different methods isalso discussed as a possibly more efficient way to propose conservationstrategies for important species of the family.

Ethnobotany of the Wild Mexican Cucurbitaceae1

This paper presents the results of a survey on the ethnobotany of the wild Mexican Cucurbitaceae. The sources of information were fieldwork in different regions of Mexico, as well as herbarium specimens and bibliographic references. A total of 34 wild species (26.5% of the 128 wild mexican species) of Cucurbitaceae are reported as used in 24 of the 32 states of Mexico. All of the species are called by one or more local names, and 23 are known by names in native languages. The uses comprise 12 categories, including human medicine (18), food (13), soap substitute (12), fodder (4), toy (3), drink (2), ornate (2), insecticide (1), animal medicine (1), handicrafts (2), container (1), and ceremonial (1), and some uses date back to pre-Hispanic and colonial times.ResumenEste artículo presenta los resultados de una investigatión etnobotánica de las especies mexicanas silvestres de la familia Cucurbitaceae. Las fuentes de informatión fueron el trabajo de campo en diferentes regiones de México, así como también ejemplares de herbario y referencias bibliográficas. Un total de 34 especies silvestres (26.5% de las 128 especies silvestres mexicanas) de Cucurbitaceae son reportadas como útiles en 24 de los 32 estados de México. Todas las especies son conocidas por uno o más nombres locales y 23 de ellas reciben nombres en lenguas nativas. Los usos registrados abarcan un total de doce categorías, incluyendo medicina humana (18), alimento (13), substituto de jabón (12), forraje (4), juguete (3), bebidas (2), ornato (2), insecticidas (1), medicina animal (1), artesanías (2), contenedores (1) y ceremonial (1), y algunos de los usos parecen remontarse a las épocas pre-Hispánica y colonial.

Crop/Weed gene flow:Cucurbita argyrosperma Huber andC. fraterna L. H. Bailey (Cucurbitaceae)

A mixed population of Cucurbita at Vado El Mow in northern Tamaulipas, Mexico showed an anomalous pattern of fruit bitterness. Some domesticated plants (C. argyrosperma andC. moschata) expressed cucurbitacin bitterness whereas some sympatric free-living plants produced non-bitter fruits. This reversal of typical cucurbitacin expression suggested gene flow between crop and weed at the site. Isozyme analysis provided little insight as to taxa involved in gene exchange, although progeny from a single free-living plant carried IDH allozymes that are associated with Mexican landraces ofC. pepo. Synthetic hybridization revealed that fertile F, hybrids are produced from crosses involvingC. fraterna as the pistillate parent andC. argyrosperma as the staminate parent. Interspecific crop/weed hybrids can produce viable progeny upon self-pollination or backcrossingto either parent, andF2 families display normal allozyme segregation. Hybrid fertility, as indicated by pollen stainability, increases in progeny produced by backcrossingfrom theC. argyrosperma parent. Interspecific hybridfertility represents a potential for crop/weed gene flow that would be realized under natural conditions if pollen flow occurs betweenC. fraterna andC. argyrosperma in the fields of Tamaulipas. Oligolectic “squash bees” (Teponapis), efficientCucurbita pollen vectors, are present at the site. Thus, it is likely that natural interspecific crop/weed hybridization has occurred at Vado El Moro and this might at least partially explain the anomalous distribution of fruit bitterness among extant populations at the site.RésuméFlujo genetico entre plantas arvenses y los cultivos. Una población mixta de Cucurbita en la localidad de Vado El Mow, Tamaulipas, en el noreste de México mostró un patron anómalo en elsabor amargo de susfrutos. Algunas plantas cultivadas deC. argyrosperma y C. moschata expresaron el sabor amargo en sus frutos, mientras se encontraron frutos dulces en algunas poblaciones silvestres o espontáneas deC. fraterna, creciendo simpátricas con las anteriores. Esta situatión es contraria a la típica expresion de las cucurbitacinas responsables del sabor amargo y sugirió la existencia dejlujo genético entre los cultivos y las plantas arvenses asociadas a ellos. El análisis de las isoenzimas proporcionó pocas respuestas respecto a los taxa involucrados en el intercambio genético, aunque las progenies de una de las plantas espontáneas llevaba aloenzimas IDH que estan asociadas a las razas Mexicanas deC. pepo. Estudios de hibridizacion artificial revelaron que es posible producir híbridos F, fértiles a! usar aC. fraterna como planta femenina y aC. argyrosperma como la planta masculina donadora de polen. Estos híbridos produjeron progenie viable mediante autopolionizaciones o retrocruzas con ambos progenitores y lasfamilias F2 desplegaron una segregatión aloenzimática normal. Los resultados de estudios de tinción para probar la viabilidad del polen, revelaron un incremento en la fertilidad híbrida de las progenies obtenidas por retrocruzas conC. argyrosperma. La fertilidad de los híbridos interespecificos representa un potential para que se produzca flujo genético silvestre-cultivo bajo condiciones naturales si el flujo de polen ocurre entreC. argyrosperma y C. fraterna en Tamaulipas. La presencia en el sitio de abejas oligolécticas de los géneros (Peponapis), eficientes vectores del polen de Cucurbita, incrementan esta posibilidad y pudiera explicar parcialmente la distributión anómala del sabor amargo en los frutos de las poblaciones de Cucurbita ahi presentes.

Population Dynamics of Agave marmorata Roezl. under Two Contrasting Management Systems in Central Mexico

Population Dynamics ofAgave marmorataRoezl. under Two Contrasting Management Systems in Central Mexico. This paper evaluates the impacts of traditional management on the population dynamics of Agave marmorata, a multipurpose, useful species that is dominant in the Zapotitlán Salinas Valley, Puebla, Mexico. During 2002–2003 and 2003–2004, we constructed matrix models for two populations—one unmanaged, the other subject to plant extraction and cutting of flowering stalks. We also conducted prospective (elasticity) and retrospective (life table response experiments) analyses. Overall, the unmanaged population had higher finite rates of increase (λ) than the managed one. This variation in λ was the result of a decrease in the individual growth and fecundity in the managed population. Survival and growth were the demographic processes with the highest contribution to λ in the unmanaged population, while survival was the most important in the managed one. Our results suggest that management and plant extraction practices could be having negative effects on the population dynamics of this plant species. Recommendations are provided in order to promote positive effects on its vital rates and regeneration capacity.ResumoDinámica de poblaciones deAgave marmorataRoezl. en dos sistemas contrastantes de manejo en el Centro de México. Este trabajo tuvo como objetivo evaluar el impacto del manejo tradicional en la dinámica de poblaciones de Agave marmorata, una especie útil multipropósito dominante en el Valle de Zapotitlán Salinas, Puebla México. Durante 2002–2003 y 2003–2004, se construyó un modelo matricial para dos poblaciones, una no manejada y otra sujeta a extracción y corte de inflorescencias. También se llevaron a cabo análisis prospectivos (elasticidad) y retrospectivos (experimentos de respuesta de tablas de vida). En términos generales, la población no manejada tuvo tasas finitas de crecimiento (λ) más altas que la manejada. Esta variación de λ fue resultado de un decremento in el crecimiento y fecundidad individual en la población manejada. La sobrevivencia y el crecimiento fueron los procesos demográficos con la más alta contribución al valor de λ en la población no manejada, mientras que la sobrevivencia fue el más importante en la población manejada. Nuestros resultados sugieren que las prácticas de manejo y extracción pudieran tener efectos negativos en la dinámica poblacional de esta especie vegetal. Se proponen algunas recomendaciones con el objeto de promover efectos positivos en sus tasas vitales y capacidad de regeneración.

Impact of climate change on the distribution of populations of an endemic Mexican columnar cactus in the Tehuacán-Cuicatlán Valley, Mexico

In this paper, we present a bioclimatic approach to (1) differentiate populations of the endemic Mexican columnar cactus Neobuxbaumia tetetzo within the Tehuacán-Cuicatlán Valley and (2) evaluate, under two possible future scenarios (years 2050 and 2080), the effects of climate change on the total species distribution in this area, as well as on groups of populations defined by their bioclimatic models. Four population groups were identified, and principal component analysis showed that the variables that explained more than 40% of the climatic variation were precipitation of the wettest quarter and temperature seasonality. Bioclimatic models under the different scenarios indicated that when the overall species distribution was analyzed, this area will probably have contracted by 19.5% by the year 2050 and 47.05% by the year 2080, whereas the separate analysis of population groups projected area contractions of 18.4% by the year 2050 and 51.95% by the year 2080. These results demonstrate the importance of exploring new approaches for evaluating and predicting current and future distribution of plant species.