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Most pine species produce high amounts of viable seeds, and this characteristic varies according to number of trees and soil conditions. The assessment of reproductive indicators under such conditions has been documented. However, in species such as Pinus martinezii, whose populations are small, scattered and fragmented, information on such reproductive characteristics is limited. The objective of this work was to evaluate cone size, reproductive indicators and inbreeding index of P. martinezii from sites with different degrees of soil degradation. Thirty cones were collected from eight trees at two sites in the state of Michoacán. The data were analyzed using a two-way ANOVA, whose factors were provenance, family and the interaction between them. In addition, a correlation was made between reproductive parameters and cone size. The values obtained per cone were: 80.6 to 129.6 potential seeds, 15.7 to 79 % developed seeds, 8.6 to 50.6 % full seeds, 39 to 91.1 % vain seeds, 20.9 to 99 % abortive ovules and 0.39 to 0.91 inbreeding index. A significant difference was observed between provenances and families in most of the evaluated variables. Reproductive indicators show a substantial loss of seeds due to abortive ovules and vain seeds, which indicates reproductive problems due to the low number of individuals. This situation is exacerbated by soil degradation. [ABSTRACT FROM AUTHOR]

Copyright of Revista Veterinaria is the property of Universidad Nacional del Nordeste and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background and aims: Sierras de Famatina are an important area of endemism, where two representatives of Trichocereus coexist, whose taxonomic identity is discussed. Trichocereus. pseudocandicans is endemic, with colorful, diurnal flowers; while, T. candicans has a wider distribution, with white and nocturnal flowers. Taking these differences into account, we carried out a morpho-anatomical study of perigonium, gynoecium and fruit, making qualitative and quantitative comparisons. The objective is to generate new information for the genus, provide reliable taxonomic traits, and make inferences about its reproductive biology. M&M: We made temporary and permanent histological preparations of flowers and fruits, using classical techniques. In addition, we analyzed 43 morpho-anatomical variables, which were statistically compared. Results: The entities present similar morpho-anatomical traits but are differentiated by the color of the perigonium and the total size of the flowers. The following characters stand out: the style presents a stilar canal and transmitter tissue, the receptacle and the ovary wall are notoriously different but intimately fused, even after fertilization, circinate ovules, among others. Only 27.9% of the variables analyzed resulted in statistically significant differences, the flowers of T. candicans being slightly larger than those of T. pseudocandicans. Conclusions: The similarity found between the taxa reaffirms their high degree of kinship, and it is possible that T. pseudocandicans is a subspecies or hybrid of T. candicans. On the other hand, the different floral traits could be due to a high phenotypic variability, influenced by the particular characteristics of the Famatina Sierras. [ABSTRACT FROM AUTHOR]

The pollinator contribution to the reproductive success of species is made from the transfer of pollen, through the visit rate, which varies according to the expression of certain floral features. Rhytidophyllum lomense (Gesnerieae) is an endemic species of Cuba with tubular flowers and other characteristics that allow to predict the pollination syndrome by hummingbirds. Other species of the tribe with this corolla design, show low reproductive success. The study was directed to three questions: Does the floral design of R. lomense correspond to a specialist pollination system? Are there high levels of pollen limitation associated with the inefficiency of the specialist pollinator? and How does floral biology and reproductive assurance mechanisms determine reproductive success? The studies were carried out in three populations and 11 variables were used to describe the floral morphology. Direct observations were made to the flowers to determine the pollinators. The autogamy capacity was calculated through the self-fertilization index and, as pollinator efficiency measures, the indexes of pollen limitation, fruits/flowers and seeds/ovules were calculated. Chlorostilbon ricordii is the only R. lomense pollinator in concordance to its floral biology. The low visit rate of the hummingbird and the values of the calculated indexes show low efficiency of the pollinator. In addition, the low value of the index of self-fertility and the high levels of hercogamy and dicogamy do not show that R. lomense is in a period of transition a mechanism of reproductive assurance such as self-fertilization. [ABSTRACT FROM AUTHOR]

Copyright of Politica y Sociedad is the property of Universidad Complutense de Madrid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Antecedentes: el cultivo de trucha ha generado un gran desarrollo a nivel industrial y artesanal, representando el 11,36 % de la producción piscícola total en Colombia. Objetivo: se analizó durante seis meses la eficiencia reproductiva de la trucha albina importada vs la trucha silvestre (Oncorhynchus mykiss), adaptada a condiciones de altura en la Estación Guairapungo de CORPONARIÑO. Métodos: los peces sexualmente maduros fueron seleccionados y apareados con base en sus características fenotípicas y registros de talla y peso, conteo de ovas por la técnica de peso, número de espermatozoides por el método hemocitómetro en cámara Neubauer. Los ejemplares fueron distribuidos en un Diseño Irrestrictamente al Azar, en tres tratamientos y cuatro réplicas, de tal manera que cada réplica estaba constituida por los embriones procedentes de los gametos de un macho y una hembra de trucha de la siguiente forma: Tl, conformado por cuatro machos y cuatro hembras silvestres; T2, cuatro hembras silvestres y cuatro machos albinos; T3, cuatro hembras y cuatro machos albinos. Las diferencias estadísticas de cada tratamiento, se determinaron mediante análisis de varianza (ANOVA) y las diferencias entre tratamientos por prueba de Tukey. Resultados: el tratamiento T2, reportó significancia estadística (p < 0,05), con relación al porcentaje de eclosión (59,72 %), producción de 426 larvas/kg, motilidad espermática de 77,05 segundos y densidad de 4,55 x 109 células/ml. Conclusiones: el cruce de machos albinos y hembras silvestres presentaron los mejores valores reproductivos. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ginecología y Obstetricia de México is the property of Federacion Mexicana de Ginecologia y Obstetricia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)