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A cytogenetic study of 62 populations of Santolina pectinata in Spain shows the existence of two ploidy levels. The diploid cytotypes with 2n = 18 occupy the eastern Betic mountains, and the tetraploid cytotypes with 2n = 36 are located on the spurs of the Iberian System. The former show a much wider ecological spectrum than the latter. Mixed cytotypes were observed in two diploid populations, with one tetraploid in each, showing different karyotypes. Three trisomic individuals were detected, one in a diploid population and the other two in a tetraploid population. Also, three hypotetraploid individuals were detected in a tetraploid population. Polyploidy is shown to be spontaneous and recurrent, promoting partial sterility in the pollen. Structural chromosomal changes, principally translocations, and local speciation through autopolyploidy are the principal factors in the evolution and diversification of this species.

Phenotypic differentiation of two tetraploid (2n = 4x = 36, 36+1B, 36+2B) populations of Santolina rosmarinifolia geographically isolated from diploid populations was investigated. The karyotype was relatively homogeneous, meiosis was regular and pollen was fertile in both cytotypes. An autopolyploid or allopolyploid origin for tetraploid cytotypes is discussed. Overall, 80.82% of all variance in achene weight, time t0, t50 and t90 of germination and accumulated germination rate was due to achene age at each ploidy level. Partition of the total phenotypic variance showed that there was extensive variation between ploidy levels. The mean of morphological characters was generally higher in polyploids. For diploid cytotypes, flower number, achene production and fruiting percentage were significantly higher than for tetraploid cytotypes. Cluster analysis indicated that the patterns of seedling morphology and development were similar in three diploid individuals and several tetraploids; the same analysis showed high similarity between diploid individuals of the natural populations, whereas tetraploid individuals showed high dissimilarity among themselves and with diploid individuals. Multiple correspondence analysis and logistic regression analysis indicated that qualitative characters contribute strongly to cytotype differentiation. The results support recognition of the tetraploid cytotypes at the subspecies level.

Santolina ageratifolia Barnades ex Asso is a natural autohexaploid (2n = 6x = 54, 54 + 1B), endemic to Teruel Province, Spain and inhabits a substrate derived from sandstone, red limolite and quartzite. Three chromosome formulae are found: 30m + 12sm + 12st, present in 52% of the descendants (52 metaphase), 24m + 5m-1sm + 18sm + 6st in 39% of the descendants (39 metaphase) and 24m + 5m-1sm + 18sm + 6st + 1B in 9% of the descendants (9 metaphase). Chiasmata are mostly interstitial rather than terminal, giving rise to the formation of cruciform structures. The predominance of bivalent configurations in the meiosis and the exclusively bivalent formation in four individuals indicate that this species has a strong tendency towards diploidization. Secondary association of bivalents is observed in the number of 2, 4-6 chromosomes associated, the average being 4.21 ± 1.20 chromosomes. The variation in the chromosomal characteristics suggests chromosome translocation and/or inversions. This species is partially sterile, with a mean pollen fertility of 40.56% and a mean fructification of 34.24%. The frequencies of multivalents and pollen fertility have a strongly significant effect on fructification percentage. Phenotypic variation in habits is not correlated with karyotype characteristics. The cytogeography of the polyploid taxa of the Santolina rosmarinifolia aggregate is discussed.

ResumenSe diseña material propio para el proceso de enseñanza-aprendizaje de las técnicas de análisis de granos de almidón en el contexto universitario de la asignatura Botánica General, y se valora la experiencia educativa mediante el modelo pedagógico de clase invertida. El estudio incluye a 150 participantes de las carreras de Biología y Ciencias Farmacéuticas de la Universidad de Cartagena, Colombia. Los estudiantes muestran una opinión muy favorable de la práctica de laboratorio, avalando el enfoque empleado. Se han logrado los objetivos propuestos, favoreciendo el aprendizaje conceptual que se refleja en las calificaciones. Se ha logrado fomentar en los estudiantes el aprendizaje activo y autónomo, y el pensamiento crítico y complejo. Palabras claves: botánica; clase invertida; granos de almidón; percepción de los estudiantes; práctica de laboratorio Laboratory Practice of Starch Grains in a University General Botany course: a Flipped Classroom Experience AbstractSpecific material was designed to teach and learn how to analyse starch grains in the context of a university General Botany course. The educational experience has been assessed through the Flipped Classroom approach. The study includes 150 participants from the departments of Biology and Pharmaceutical Sciences of the University of Cartagena, Colombia. The students had a favourable opinion about the laboratory practice regarding the Flipped Classroom approach. The experience achieved the proposed teaching objectives and the learning outcome was favorable, resulting in good lab practice scores. Active and independent learning has been promoted among students as well as complex and critical thinking. Keywords: botany; flipped classroom; starch grains; student perception; laboratory practiceFormación Universitaria Vol. 11(1), 87-104 (2018) http://dx.doi.org/10.4067/S0718-50062018000100087 Práctica de Laboratorio de Granos de Almidón en un Curso de Universitario de BotánicaRivero-Guerra 88Formación Universitaria Vol. 11 Nº 1 -2018 INTRODUCCIÓNEl aprendizaje tiene un carácter ubicuo (Burbules, 2012; Pozo y Monereo, 2010) y la sociedad genera nuevas demandas de formación y educación para la ciudadanía las cuales son asumidas por todos los niveles educativos imperantes (Perry, 2013;Zimmerman, 2002). Siendo los profesores y estudiantes sujetos activos de las nuevas tareas y de las acciones a realizar (Butler y Schnellert, 2012), principalmente en el saber hacer; resaltando la importancia del conocimiento previo, vinculando lo aprendido con el nuevo que se adquiere; enfatizando en la motivación de los estudiantes para el éxito del proceso de aprendizaje, estableciendo metas y competencias de aprendizaje en lugar de metas de rendimiento. El estudiante adquiere un rol de gestor de los procesos cognitivos que conlleva el aprendizaje autónomo, controlando todo el proceso. Dicha labor de gestión implica la planificación, control y dirección de los procesos cognitivos hacia una meta, las cuales deben de efectuarse con concentración, esfuerzo y motivación. Don...

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Santolina impressa (2n = 2x = 18) is an endemic species of Portugal, with restricted geographical distribution. The present study aimed to explore its chromosomal variation in respect to chromosome morphology, meiotic behaviour, and effects on pollen stainability and fecundity. Its karyotype formula was found to be either 12m + 2m sat + 2sm sat + 2st (75% of the individuals) or 12m + 2m sat + 3sm + 1sm sat (25% of the individuals). Univalents were observed in 29.21% of the meiocytes. Chromosome fragments due to breakage in the chromosome arm were observed in 10 meiocytes only (11.23% of the meiocytes). Chains and rings of trivalents were observed in 14.60% of the meiocytes (one trivalent per meiocyte was observed). Chains and rings of quadrivalents were observed in 21.34% and 11.23% of the meiocytes, respectively, with a range of 0-1 per cell. Nine plants (40.90% of the total) with 2n = 2x = 18 + 2B showed a quadrivalent configuration in diakinesis. Twenty abnormal anaphases with delayed disjunction of the four nonhomologous and the two homologous chromosomes were observed. Simple chromosome bridges without fragments and interchromosomal adhesions were observed in 35.95% of the anaphases analyzed. B chromosomes showed bivalent association in diakinesis and their segregation at anaphase I was normal. Pollen was found to be fertile (mean ± s.d. = 89.57 ± 47.14%); the effect of univalent frequency and frequency of abnormal anaphase I on pollen stainability was strong and statistically significant.

La familia Asteraceae está representada en la Flora de Ecuador por un total de 310 táxones endémicos. Están agrupadas en 4 subfamilias (Asteroideae, Barnadesioideae, Cichorioideae y Mutisioideae), 16 tribus y 89 géneros. Doscientas setenta y dos táxones (87,74%) restringen su hábitat a la región andina. Los niveles más altos de endemismos están asociados a los Andes, mayoritariamente desde el bosque andino alto hasta el páramo, y a las Islas Galápagos. Los géneros con mayor riqueza de endemismos son Mikania (26), Pentacalia (23), y Gynoxys (20). Tres géneros monotípicos son endémicos: Cyathomone, Idiopappus y Trigonopterum. Los géneros Darwiniothamnus, Kingianthus, Lecocarpus, y Scalesia también son endémicos. La diversidad de la familia se incrementa desde los 2000 m a 3000 m, alcanzando su mayor riqueza entre los 2900-3000 m, con dominancia de las plantas arbustivas (195 especies, 1 subespecie, 2 variedades) y herbáceas (97 especies). Ciento veinteseis especies tienen categoría de vulnerable, 90 están en peligro de extinción y 24 están en estado crítico de amenaza. Las temperaturas y precipitaciones medias anuales varían significativamente entre los sectores biogeográficos.