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In plants of the perennial, deciduous herb Talinum triangulare, crassulacean acid metabolism (CAM) is induced by drought; therefore, CAM may be an adaptation to water deficit in this species. The present study was undertaken to determine the effects of water deficit on fecundity and CAM in plants of T. triangulare. Plants were grown from seed in the greenhouse and the life table was constructed with dynamic cohorts. CAM was induced by drought in plants as young as 45 days old, and its induction was associated with a significant rise in fecundity; values of survival beta mean fecundity by age-class were 30-50% higher in plants subjected to drought than in control plants due to a rise in fecundity. Plants subjected to drought produced more and lighter seeds, which germinated faster than their watered controls. These characteristics could be advantageous for a colonizing species such as T. triangulare. Plants obtained from the germination of seeds of plants subjected to drought did not show higher values of nocturnal acid accumulation when subjected to drought than the droughted offspring of watered plants but they showed higher survival and an earlier and higher reproductive effort than plants obtained from the germination of seeds of watered plants. The fact that values of survival beta mean fecundity were higher in plants subjected to drought than in watered plants suggests, within the context of the life history, that characters associated with the CAM syndrome may be adaptive.Key words: fitness, inducible CAM, life table.

Peñas, J., Lorite, J., Alba-Sánchez, F. & Taisma, M.A. 2011. Selfincompatibility, floral parameters, and pollen characterization in the narrow endemic and threatened species Artemisia granatensis (Asteraceae). Anales Jard. Bot. Madrid 68(1): 97-105.Artemisia granatensis Boiss. is a paradigmatic species for plant conservation in Spain and Europe. It is a critically endangered (CR) endemic species growing above 2500 m in the Sierra Nevada (southern Spain). Natural populations have been considerably devastated in the past due to intensive human exploitation for folk medicine. The sparse available data concerning the reproductive biology of this species under natural conditions indicate a low reproductive success. To provide additional information on the reproductive biology of A. granatensis, and consequently information useful for the management and conservation of this species, we studied the breeding system through pollen-tube growth. In addition, some floral and pollen traits were recorded. No differences were found between populations in terms of the morphological traits of flowers and inflorescences. A. granatensis is an anemophilous species, and the data indicate that pollen transfer may be limited between isolated populations, and so contributing to an extremely low fruit-set. Results show A. granatensis is selfincompatible, probably with a sporophytic self-incompatibility system, and with no evidence of partial self-incompatibility. Reproductive traits, related to pollen morphology and settling speed may explain the low rate of recruitment in the small populations separated by geographical barriers.Keywords: reproductive biology, pollen-tube growth, endemic and threatened species, conservation. Artemisia granatensis Boiss. es una especie paradigmática en la conservación de flora a nivel español y europeo. Es una especie catalogada como En Peligro Crítico (CR) endémica de Sierra Nevada (sur de España), donde habita por encima de los 2500 m. Las poblaciones naturales han sido casi exterminadas en el pasado debido a una recolección masiva de la especie, utilizada en medicina popular. Los escasos datos disponibles acerca de su biología reproductiva en condiciones naturales indican que existe un bajo éxi to reproductivo. Con el objetivo de proporcionar información adicional acerca de la biología reproductiva de A. granatensis, útil para la conservación y el manejo de la especie, evaluamos el sistema de compatibilidad a través del crecimiento del tubo polínico. Además se registraron datos sobre algunos rasgos florales y polí-nicos de la especie. No se encontraron diferencias entre poblaciones en términos de rasgos morfológicos de flores e inflorescencias. A. granatensis es una especie anemófila para la cual los datos obtenidos sobre capacidad de dispersión sugieren que la transferencia de polen podría ser difícil entre poblaciones aisladas o muy distanciadas, pudiendo ser un factor más a tener en cuenta entre las causas que provocan un limitado éxito reproductivo y una paupérrima producción de semillas. ...

En este trabajo se proporciona información de los usos medicinales atribuidos a Prosopis juliflora (Sw.) DC. por habitantes de cinco localidades rurales de la Peninsula Paraguaná (Estado Falcon, Venezuela). Se realizaron entrevistas semi-estructuradas a 51 informantes, de entre 23 y 86 años de edad, naturales de la península de Paraguaná. Todos los entrevistados atribuyeron alguna propiedad curativa a hojas, frutos y/o tallos de P. juliflora. Los mayores porcentajes de uso medicinal de la especie se refirieron a patologías traumatológicas, oftalmológicas y de la función sexual masculina. Algunos otros usos medicinales reportados en menor proporción incluyen tratamientos para la diabetes, enfermedades del sistema digestivo, parasitosis, enfermedades eruptivas, coadyuvante en casos de malestar general, cálculos renales y cáncer. Los resultados constituyen la primera compilación de usos medicinales de P. juliflora en Venezuela, y permiten establecer bases para el desarrollo de investigaciones tendientes a la determinación de su prospección bioquímica y farmacológica.

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