Cristina Hilda Rolleri

IR - spectroscopic characterization of biominerals in marattiaceaeus ferns

(Caracterizacao de biominerais por espectroscopia infravermelha em Marattiaceae). Mostras de frondes dos fetos eusporangiados dos generos Angiopteris, Christensenia, Danaea e Marattia (Marattiaceae), foram investigadas por espectroscopia infravermelha sob diferentes condicoes experimentais. Os resultados confirmaram relatos anteriores sobre a acumulacao de silica biogenica (SiO2), em tecidos desses fetos e tambem mostraram, pela primeira vez, a presenca de oxalato de calcio nesse grupo de plantas, provavelmente na forma de weddellite. A capacidade de mineralizar SiO2, para produzir e acumular silica biogenica, sugere que esta caracteristica seja uma propriedade generica dos membros da familia Marattiaceae.

Epidermal Morphology of the Pinnae of Angiopteris, Danaea, and Marattia

This is a study of adult epidermis morphology in 17 species of Angiopteris Hoffm., Danaea J. E. Smith, and Marattia Swartz. Epidermal patterns, adult stomata, indument, and idioblasts were studied. Hill and Camus (1986) made an overview of characters of some extant species of Marattiales as part of a cladistic study of extant and fossil members of the order. The epidermal characters they used were subsidiary cells of the stomata, dimensions of the stomata, walls of epidermal cells, and idioblasts. The only character of indument they included in their study was the presence or absence of scales. Rolleri et al. (1987) made the first detailed study dealing with pinna and pinnule indument in the Marattiaceae, although Holttum (1978) had made some general comments on petiole and rhizome scales of Angiopteris, illustrating two species. He suggested that Angiopteris pinna trichomes were diagnostic but needed detailed study. Rolleri et al. (1987) strongly pointed out that epidermal characters are diagnostic at the species level in the Marattiaceae and speculated on generic affinities within the Marattiales.

Spore morphology and ornamentation in the genus Blechnum (Blechnaceae)

Abstract A study of the spores of 64 neotropical and palaeotropical taxa of the genus Blechnum was performed using scanning electron microscopy (SEM). Two basic types of perispores were recognised: perispore smooth or only slightly ornamented (laevigate, with micro-granules or micro-lamellae, venulose and rugulate), and perispore ornamented (rugate, low reticulate, cristate-reticulate, orbiculate, and colliculate). SEM observations allow for distinguishing differences in the structure of perispores, but the character does not correlate with the ornamentation. The smooth exospore predominates among the studied species. Results suggest that perispore characters have important diagnostic value, since different combinations of ornamentation/structure were found among the studied species. Moreover, when spore characters are considered together with other morphological traits of the sporophytes and the habit of plants, ornamentation of spores becomes a useful complementary feature at the specific level. The results are discussed in light of the recent systematic studies and emphasise that any eventual subdivision of the genus Blechnum must include characters of the sporophyte as well as spore features to ensure a more robust classification than the previously proposed. The spores also show a significant affinity between Blechnum and other genera of Blechnaceae, which was also suggested by recent phylogenetic studies.

Caracteres diagnósticos foliares en Isoetes (Pteridophyta, Isoetaceae)

Abstract Foliar characters were studied in 25 European, North African, North American, and South American terrestrial, amphibious, and aquatic taxa of the genus Isoetes L. (Pteridophyta, Isoetaceae). The foliar characters investigated have a variable diagnostic value. The presence and types of cuticular ornamentations, types of margins, epidermal patterns and cell ratios of the epidermis, types of IPP (intercellular pectic protuberances) in the cells of the leaf diaphragms, epidermal patterns and cell ratios of velum, epidermal patterns, and nature of walls in the adaxial epidermis of sporangia may be good diagnostic specific characters that should be included in taxonomic descriptions. Transverse sections of the microphylls, the types and distribution of collenchyma (fascicular, lacunar, or partially laminar collenchyma, with the latter two types described here for the first time), the cell types of leaf diaphragms, the presence of IPP in these cells, the partial or complete endodermis in the air chambers, and the presence of a persistent mucilage-secreting or an early lignified ligule are features that characterize species groups in Isoetes. The mucilage-secreting ligula and the types of endodermis can be considered as generic traits in Isoetes. The genus was largely considered as lacking good diagnostic characters or having rather environmentally influenced traits, two concepts that are discussed here after presentation of the new evidence.

Huperzia reflexa y Lycopodiella cernua (Lycopodiales-Pteridophyta): dos nuevas citas para el NO de la Argentina y actualizaciones sobre su morfología

Rolleri, C. H.; Martinez, O. G. & Prada, C. 2010. Huperzia reflexa and Lycopodiella cernua (Lycopodiales-Pteridophyta): two new re- cords to the NW of Argentina, and updates on their morphology. Bot. Complut. 34: 41-48. Huperzia reflexa and Lycopodiella cernua are recorded for the first time for the northwest of Argentina; along with the new records, the cha- racters of the leaf morphology and spores are analyzed, and updated descriptions and geographical distribution of both taxa are also given. Three of the four genera of the Lycopodiaceae are present so far in the area: Huperzia, Lycopodium and Lycopodiella, and the number of species come to nine. To facilitate the recognition of all taxa, this paper also includes a key for their determination.

Morphology of the sporophyte and gametophyte of the swamp fern, Blechnum serrulatum (Blechnaceae, Pteridophyta)

In the present paper, we provide a revised, comprehensive description of the sporophyte and gametophyte of the swamp fern, Blechnum serrulatum Rich., from neo- and paleotropical localities. External and internal characters of the sporophyte were analysed, including axes, laminae, pinnae, indusia and spores. Intercellular pectic connections of the parenchyma of the rhizomes are reported for the first time. In stipes, cell walls of the aerenchyma tissue contain filamentous protuberances that are composed primarily of cellulose but contain also fatty substances. The morphology of the gametophyte, from spore germination to gametangia formation, is discussed. The taxonomic significance of the characters is considered, especially in regard to the relationship between B. serrulatum and the closely related B. indicum.

GERMINACION DE LA ESPORA,MORFOLOGIA DEL GAMETOFITO Y EXPRESION SEXUAL DE POLYPODIUM FEUILLEI BERTERO (POLYPODIACEAE)

En este trabajo se estudia el desarrollo morfologico y la expresion sexual de los gametofitos de Polypodium feuillei. Se emplearon cultivos multisporos en agar nutritivo para sembrar esporas. En menos de tres semanas se observo germinacion vigorosa, alcanzandose porcentajes del 78%, siendo el patron de germinacion del tipo Vittaria. El gametofito de P. feuillei presenta una fase filamentosa alargada, cuyo crecimiento se prolonga durante unas dos semanas, seguida de una fase laminar. Hacia la decima semana tras la germinacion, los gametofitos alcanzan la forma cordado-alada y presentan abundantes pelos en los margenes y en la superficie abaxial de la lamina antes de la madurez. Este modelo ontogenico de desarrollo se ajusta al tipo Drynaria. En su madurez, hacia la vigesima quinta semana, P. feuillei desarrolla inicialmente protalos de sexo femenino, que adquieren mayor tamano y vigor que los masculinos. Muy pocos gametofitos exhiben condicion bisexuada.

Nuevo recuento cromosómico para Blechnum hastatum (Blechnaceae-Pteridophyta), con un estudio de la ontogenia y tipos de leptoporangios adultos

Se da a conocer un nuevo recuento cromosomico para Blechnum hastatum y se presenta un analisis de la ontogenia del leptosporangio en ese taxon y en B. occidentale, asi como una comparacion con leptosporangios adultos de otras especies y subespecies del genero, como B. australe subsp. auriculatum, B. glandulosum y B. mochaenum subsp. mochaenum. En relacion con la citologia de B. hastatum, se contaron 33 bivalentes en diacinesis, lo que indica que se trata de un diploide con un numero cromosomico 2n=66, un dato que confrma un recuento previo y ubica al taxon en la secuencia de numeros cromosomicos basicos conocida para el genero, es decir x=33, que es el mas frecuente. En el estudio de la ontogenia de los esporangios se comprobo que se forman a partir de iniciales que se encuentran sobre la comisura y sobre la base del indusio; que desarrollan un pedicelo formado por celulas cortas en tres hileras en B. hastatum, la condicion aparentemente mas comun registrada para el genero, y celulas largas, tambien en tres hileras, en B. occidentale. Los pedicelos alcanzan su maximo desarrollo antes de que la capsula llegue a la etapa adulta. Los estomios tienen 6-8 celulas, las de la abertura engrosadas en forma de labio. Los anillos son verticales de hasta 14 celulas engrosadas en B. australe subsp. auriculatum y B. glandulosum, hasta 18 en B. hastatum y hasta 21 en B. mochaenum subsp. mochaenum y B. occidentale, llegan hasta la base misma de las capsulas y el numero de celulas engrosadas aparece como un caracter diagnostico nuevo en el genero.

Morfología, taxonomía y caracterización de siete especies neotropicales del género Canna (Cannaceae-Zingiberales)

Se investigaron los caracteres de rizomas, hojas, inflorescencias, flores, granos de polen y semillas de siete especies del genero Canna con el fin de evaluar su valor diagnostico. Las especies estudiadas fueron: C. ascendens, C. coccinea, C. compacta, C. glauca, C. indica, C. paniculata y C. variegatifolia. Los caracteres analizados fueron: ramificacion de los rizomas; contorno, tamano, relacion largo/ancho, apice, base, textura, superficie, color de la lamina, margen y vena primaria, tipos y localizacion del indumento y venacion de las hojas; tipos y longitud de las inflorescencias, longitud de sus entrenudos basales, numero de ejes y de bracteas por nudo, angulo entre ejes, numero de paracladios, color de las bracteas, vainas y ejes de las inflorescencias; color, numero de piezas y longitud de las flores, longitud del tubo floral, posicion y enrollamiento del labelo; tamano y ornamentacion de los granos de polen; tamano, forma y color de las semillas. Los tipos de rizomas, de inflorescencias, el numero de piezas florales, de estaminodios, la anchura de los estaminodios, el color, posicion y enrollamiento del labelo, el color y tamano de las semillas, caracterizan grupos de especies. Los caracteres foliares tienen valor diagnostico especifico y su conjunto resulta util para determinar las especies en ausencia de flores. El indumento es raro en Canna y se encontro solamente en C. compacta y C. paniculata. Los caracteres florales de color, tamano floral y longitud del tubo son constantes y resultan especificos. El contorno y apice de estaminodios y el apice del labelo varian en flores del mismo individuo y carecen de valor diagnostico. El polen es inaperturado con exina equinada en todos los taxones, pero el tamano de los granos, la longitud y la densidad de las espinas varian en el nivel especifico. La variacion fenotipica en individuos de una misma colonia es muy frecuente en el genero, por lo que se concluye que la mejor via para su reconocimiento y descripcion es utilizar una combinacion de varios caracteres. Se da una descripcion actualizada de las especies estudiadas, datos sobre su taxonomia, distribucion geografica, ecologia y una clave para determinarlas.

Sporogenesis, sporoderm and mature spore ornamentation in Lycopodiaceae

Sporogenesis, sporoderm and mature spore ornamentation in Lycopodiaceae. Studies on reproductive aspects, spore morphology and ultrastructure of Lycopodiaceae are not very common in the scientific literature, and constitute essential information to support taxonomic and systematic relationships among the group. In order to complete existing information, adding new and broader contributions on these topics, a comparative analysis of the sporogenesis ultrastructure, with emphasis on cytological aspects of the sporocyte coat development, tapetum, monoplastidic and polyplastidic meiosis, sporoderm ontogeny and ornamentation of the mature spores, was carried out in 43 taxa of eight genera of the Lycopodiaceae: Austrolycopodium, Diphasium, Diphasiastrum, Huperzia (including Phlegmariurus), Lycopodium, Lycopodiella, Palhinhaea and Pseudolycopodiella growing in the Andes of Colombia and the Neotropics. For this study, the transmission electron microscopy (TEM) samples were collected in Cauca and Valle del Cauca Departments, while most of the spores for scanning electron microscopy (SEM) analysis were obtained from herbarium samples. We followed standard preparation procedures for spore observation by TEM and SEM. Results showed that the sporocyte coat is largely composed by primary wall components; the sporocyte develop much of their metabolic activity in the production of their coat, which is retained until the spores release; protective functions for the diploid cells undergoing meiosis is postulated here for this layer. The abundance of dictyosomes in the sporocyte cytoplasm was related to the formation and development of the sporocyte coat. Besides microtubule activity, the membrane of sporocyte folds, associated with electrodense material, and would early determine the final patterns of spore ornamentation. Monoplastidic condition is common in Lycopodium s.l., whereas polyplastidic condition was observed in species of Huperzia and Lycopodiella s. l.. In monoplastidic species, the tapetum presents abundant multivesicular bodies, while in polyplastidic species, the secretory activity of the tapetum is less intense. Sporoderm development is centripetal, exospore is the first formed layer, then the endospore and, if present, perispore is the final deposited layer. Adult spores of the Lycopodiaceae showed two patterns of ornamentation: negative or caviform (foveolate spores) and positive or muriform ornamentation, the latter with two subtypes (rugate and reticulate spores). The spores of Huperzia are characteristically foveolate, the rugate spores were found in a few species of Huperzia and in all of the Lycopodiella s. l. taxa studied, while Lycopodium s.l. spores bear reticulate ornamentation. Numerous ornamentation traits are diagnostic at the specific level. The types of ornamentation found do not support the recent extreme fragmentation of the family in several genera, but could match, a priori, with the idea of three subfamilies. The findings of sporogenesis, extremely similar in all taxa studied, point more to consider fewer genera, more comprehensive, than the recent, marked splitting of the family. Rev. Biol. Trop. 62 (3): 1161-1195. Epub 2014 September 01.