Seedling distribution and seed germination of chilean lucumo (Pouteria splendens) in Los Molles, Chile

Indexación: Web of Science; Scielo.Pouteria splendens (lúcumo chileno, palo colorado) es un árbol endémico de Chile central con problemas de conservación. Es la única especie representante de la familia Sapotaceae en el país y se conoce muy poco de su ciclo de vida. En este trabajo describimos el patrón de distribución espacial de plántulas en la población remanente de mayor tamaño de la especie, e investigamos el efecto de la disponibilidad de agua, la presencia de pericarpo en las semillas y de la hojarasca en la capacidad de germinación. La densidad de plántulas fue mayor bajo el dosel de las plantas madres, que fuera de estas. Solo la disponibilidad de agua tuvo un efecto significativo sobre la germinación. La especie tiene el potencial de regenerar, en futuros planes de conservación y restauración de la especie hay que aprovechar el efecto nodriza que estaría ejerciendo el dosel.Pouteria splendens (Chilean lucumo, red wood) is an endemic and endangered tree from Central Chile. It is the only member of the Sapotaceae family in the country and little is known about his life cycle. In this work we described the spatial distribution of seedlings in the biggest remained population of the species, and we investigated the effect of the water availability, presence of pericarp in the seeds and the leaf litter on the capacity of germination in the species. Seedling density was higher under the canopy of mother plants, than outside its. Only water availability had a significant effect on the germination. The species has the potential to regenerate, in future plans of conservation and restoration of the species must take advantage the nurse effect of the canopy.http://ref.scielo.org/wt65f

Reproductive phenology of Pouteria splendens (Sapotaceae)

Indexación: Web of Science; ScieloPouteria splendens (A.DC.) Kuntze (lúcumo silvestre, palo colorado) es un arbusto endémico con problemas de conservación de Chile central. Es la única especie representante de la familia Sapotaceae en el país y se conoce muy poco de su ciclo de vida. Se estudió su fenología reproductiva durante la primavera y verano, desde septiembre 2007 hasta abril 2008, en la población remanente más grande, localizada en Los Molles (V Región de Valparaíso). Se encontró un incremento en la producción de yemas florales, flores y frutos desde septiembre a febrero, decayendo en marzo. Al igual que en otras especies de ambientes mediterráneos, el máximo en la formación de botones florales, flores y frutos ocurrió en época de verano, durante febrero. También detectamos una alta sincronía en la fenología entre los individuos en la población estudiada. PALABRAS CLAVE: Planta amenazada, floración, fructificación, lúcumo silvestre.Pouteria splendens (A.DC.) Kuntze (lúcumo silvestre, palo colorado) is an endemic and in dangered tree from Central Chile. It's the only member of the Sapotaceae family in the country and little is known about his life cycle. We studied the reproductive phenology during Spring and Summer, from September 2007 to April 2008, on the biggest remained population of P. splendens, located in Los Molles (V Región Valparaíso). We recorded an increase in the production of flower buds, flowers and fruits from September to February, decaying in March. According with other species from Mediterranean environments, the peak of flower buds, flowers and fruits was recorded during Summer, in February. We also detected a high synchrony in the phenology among the individuals within the population. KEYWORDS: Endangered plant, flowering, fructification, lúcumo silvestre.http://ref.scielo.org/k9sbc

Fenología reproductiva de Pouteria splendens (Sapotaceae)

Pouteria splendens (A.DC.) Kuntze (lúcumo silvestre, palo colorado) is an endemic and in dangered tree from CentralChile. It´s the only member of the Sapotaceae family in the country and little is known about his life cycle. We studiedthe reproductive phenology during Spring and Summer, from September 2007 to April 2008, on the biggest remainedpopulation of P. splendens, located in Los Molles (V Región Valparaíso). We recorded an increase in the productionof flower buds, flowers and fruits from September to February, decaying in March. According with other species fromMediterranean environments, the peak of flower buds, flowers and fruits was recorded during Summer, in February. Wealso detected a high synchrony in the phenology among the individuals within the population.Pouteria splendens (A.DC.) Kuntze (lúcumo silvestre, palo colorado) es un arbusto endémico con problemas deconservación de Chile central. Es la única especie representante de la familia Sapotaceae en el país y se conoce muy pocode su ciclo de vida. Se estudió su fenología reproductiva durante la primavera y verano, desde septiembre 2007 hastaabril 2008, en la población remanente más grande, localizada en Los Molles (V Región de Valparaíso). Se encontró unincremento en la producción de yemas florales, flores y frutos desde septiembre a febrero, decayendo en marzo. Al igualque en otras especies de ambientes mediterráneos, el máximo en la formación de botones florales, flores y frutos ocurrióen época de verano, durante febrero. También detectamos una alta sincronía en la fenología entre los individuos en lapoblación estudiada

Carpobrotus edulis (L.) N.E. Br. (Aizoaceae) y su presencia en la flora de Chile

The genus Carpobrotus was represented on the Chilean flora only by native species C. chilensis. However, we found that the speciesnative of South Africa C. edulis is naturalized in coastal areas. We report it for first time as an alien species for the Chilean territory.The genus Carpobrotus was represented on the Chilean flora only by native species C. chilensis. However, we found that the speciesnative of South Africa C. edulis is naturalized in coastal areas. We report it for first time as an alien species for the Chilean territory

Invasive and non-invasive congeneric Centaurea (Asteraceae) show contrasting patterns of herbivory by snails

Background and aims – Once introduced into new regions, exotic species often experience shifts in resource allocation in response to the different environmental conditions found in the introduction range. Plants naturally respond to specialist herbivores with quantitative defences, by producing large amounts of toxic and non-toxic compounds that typically difficult digestion (e.g. tannins, cellulose), and to generalist herbivores with qualitative defences, like specialized noxious chemicals (e.g. alkaloids). The Shifting Defence Hypothesis (SDH) poses that invasive plants decrease the production of defences against specialist herbivores in their introduction range, where specialist herbivores are usually absent, while boosting the production of defences against generalist herbivores. Methods – We empirically assessed the response of a generalist herbivore, the common garden snail (Helix aspersa), to feeding with leaves of the annual herb Centaurea sulphurea, native to Europe and naturalized in North America; and the congeneric species C. solstitialis, which is also native to Europe and invasive in the Americas. Key results – Snails fed with leaves from Spanish native populations the non-invasive C. sulphurea grew significantly less compared to snails fed with leaves from non-native California. For snails fed with the invasive C. solstitialis significant differences were also found among regions, but the response was more complex, depending on population, with snails fed with Turkish and Australian plants presenting higher growth rates than the rest of the regions. Conclusions – Overall, our results stressed the importance of colonization history in shaping adaptive responses, and the stochasticity associated with colonization events of two closely related species, with contrasting invasive success and responses to herbivory.Fil: Filipe, João C.. Universidad de Coimbra; PortugalFil: Jorge, Andreia. Universidad de Coimbra; PortugalFil: Eren, Ozkan. Adnan Menderes Universitesi; TurquíaFil: Sotes, Gastón. Universidad de Concepción. Facultad de Ciencias Naturales y Oceanográficas. Departamento de Botánica; Chile. Universidad de Chile; ChileFil: Hierro, Jose Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Montesinos, Daniel. Universidad de Coimbra; Portuga

Experimental admixture among geographically disjunct populations of an invasive plant yields a global mosaic of reproductive incompatibility and heterosis

1. Invasive species have the ability to rapidly adapt in the new regions where they are introduced. Classic evolutionary theory predicts that the accumulation of genetic differences over time in allopatric isolation may lead to reproductive incompatibilities resulting in decreases in reproductive success and, eventually, to speciation. However, experimental evidence for this theoretical prediction in the context of invasive species is lacking. We aimed to test for the potential of allopatry to determine reproductive success of invasive plants, by experimentally admixing genotypes from six different native and non‐native regions of Centaurea solstitialis, an invasive forb for which preliminary studies have detected some degree of reproductive isolation between one native and non‐native region. 2. We grew plants under common garden conditions and outcrossed individuals originating from different source populations in the native and introduced range to evaluate reproductive success in terms of seed to ovule ratio produced. We also assessed geographical and genetic isolation among C. solstitialis regions as a potential driving factor of reproductive success. 3. Experimental admixture generated mixed fitness effects, including significant increases, decreases and no differences in reproductive success as compared to crosses within population (control). Centaurea solstitialis invasive populations in the Americas generated preponderantly negative fitness interactions, regardless of the pollen source, suggesting selection against immigrants and reinforcement. Other non‐native populations (Australia) as well as individuals from the native range of Spain demonstrated an increase in fitness for between‐region crosses, indicating inbreeding. These differences show an asymmetrical response to inter‐regional gene flow, but no evidence of isolation by distance. 4. Synthesis. The speed of adaptation and the accumulation of reproductive incompatibilities among allopatric populations of invasive species might be more rapid than previously assumed. Our data show a global mosaic of reproductive outputs, showcasing an array of evolutionary processes unfolding during colonization at large biogeographical scales

Experimental admixture among geographically disjunct populations of an invasive plant yields a global mosaic of reproductive incompatibility and heterosis

Invasive species have the ability to rapidly adapt in the new regions where they are introduced. Classic evolutionary theory predicts that the accumulation of genetic differences over time in allopatric isolation may lead to reproductive incompatibilities resulting in decreases in reproductive success and, eventually, to speciation. However, experimental evidence for this theoretical prediction in the context of invasive species is lacking. We aimed to test for the potential of allopatry to determine reproductive success of invasive plants, by experimentally admixing genotypes from six different native and non-native regions of Centaurea solstitialis, an invasive forb for which preliminary studies have detected some degree of reproductive isolation between one native and non-native region. We grew plants under common garden conditions and outcrossed individuals originating from different source populations in the native and introduced range to evaluate reproductive success in terms of seed to ovule ratio produced. We also assessed geographical and genetic isolation among C. solstitialis regions as a potential driving factor of reproductive success. Experimental admixture generated mixed fitness effects, including significant increases, decreases and no differences in reproductive success as compared to crosses within population (control). Centaurea solstitialis invasive populations in the Americas generated preponderantly negative fitness interactions, regardless of the pollen source, suggesting selection against immigrants and reinforcement. Other non-native populations (Australia) as well as individuals from the native range of Spain demonstrated an increase in fitness for between-region crosses, indicating inbreeding. These differences show an asymmetrical response to inter-regional gene flow, but no evidence of isolation by distance. Synthesis. The speed of adaptation and the accumulation of reproductive incompatibilities among allopatric populations of invasive species might be more rapid than previously assumed. Our data show a global mosaic of reproductive outputs, showcasing an array of evolutionary processes unfolding during colonization at large biogeographical scales.Fil: Irimia, Ramona E.. Eberhard Karls Universität Tübingen; Alemania. Universidad de Coimbra; PortugalFil: Hierro, Jose Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; ArgentinaFil: Branco, Soraia. Universidad de Coimbra; PortugalFil: Sotes, Gastón Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias de la Tierra y Ambientales de La Pampa. Universidad Nacional de La Pampa. Facultad de Ciencias Exactas y Naturales. Instituto de Ciencias de la Tierra y Ambientales de La Pampa; Argentina. Universidad de Chile; ChileFil: Cavieres, Lohengrin A.. Universidad de Chile; Chile. Universidad de Concepción; ChileFil: Eren, Ozkan. Adnan Menderes Universitesi; TurquíaFil: Lortie, Christopher J.. University of York; Reino UnidoFil: French, Kristine. No especifíca;Fil: Callaway, Ragan M.. University of Montana; Estados UnidosFil: Montesinos, Daniel. Universidad de Coimbra; Portuga

Extensive analysis of native and non-native Centaurea solstitialis L. populations across the world shows no traces of polyploidization

Centaurea solstitialis L. (yellow starthistle, Asteraceae) is a Eurasian native plant introduced as an exotic into North and South America, and Australia, where it is regarded as a noxious invasive. Changes in ploidy level have been found to be responsible for numerous plant biological invasions, as they are involved in trait shifts critical to invasive success, like increased growth rate and biomass, longer life-span, or polycarpy. C. solstitialis had been reported to be diploid (2n = 2x = 16 chromosomes), however, actual data are scarce and sometimes contradictory. We determined for the first time the absolute nuclear DNA content by flow cytometry and estimated ploidy level in 52 natural populations of C. solstitialis across its native and non-native ranges, around the world. All the C. solstitialis populations screened were found to be homogeneously diploid (average 2C value of 1.72 pg, SD = ±0.06 pg), with no significant variation in DNA content between invasive and non-invasive genotypes. We did not find any meaningful difference among the extensive number of native and non-native C. solstitialis populations sampled around the globe, indicating that the species invasive success is not due to changes in genome size or ploidy level