Photoprotection enhanced by red cell wall pigments in three East Antarctic mosses

BACKGROUND: Antarctic bryophytes (mosses and liverworts) are resilient to physiologically extreme environmental conditions including elevated levels of ultraviolet (UV) radiation due to depletion of stratospheric ozone. Many Antarctic bryophytes synthesise UV-B-absorbing compounds (UVAC) that are localised in their cells and cell walls, a location that is rarely investigated for UVAC in plants. This study compares the concentrations and localisation of intracellular and cell wall UVAC in Antarctic Ceratodon purpureus, Bryum pseudotriquetrum and Schistidium antarctici from the Windmill Islands, East Antarctica. RESULTS: Multiple stresses, including desiccation and naturally high UV and visible light, seemed to enhance the incorporation of total UVAC including red pigments in the cell walls of all three Antarctic species analysed. The red growth form of C. purpureus had significantly higher levels of cell wall bound and lower intracellular UVAC concentrations than its nearby green form. Microscopic and spectroscopic analyses showed that the red colouration in this species was associated with the cell wall and that these red cell walls contained less pectin and phenolic esters than the green form. All three moss species showed a natural increase in cell wall UVAC content during the growing season and a decline in these compounds in new tissue grown under less stressful conditions in the laboratory. CONCLUSIONS: UVAC and red pigments are tightly bound to the cell wall and likely have a long-term protective role in Antarctic bryophytes. Although the identity of these red pigments remains unknown, our study demonstrates the importance of investigating cell wall UVAC in plants and contributes to our current understanding of UV-protective strategies employed by particular Antarctic bryophytes. Studies such as these provide clues to how these plants survive in such extreme habitats and are helpful in predicting future survival of the species studied.

Uso de organismss vegetales no vasculares como ndicadores de contaminación atmmosférica urbana (tunja, boyacá, Colombia) / Use of Non Vascular Plant Organisms as Indicators of Urban Air Pollution (Tunja, Boyacá, Colombiano)

Los líquenes y briófitos son organismos útiles en la determinación de la calidad del aire. En la ciudad de Tunja (departamento de Boyacá, Colombia), es evidente la escasez de zonas verdes por el aumento en las construcciones, lo que contribuye al detrimento de la pureza atmosférica y trae consigo el deterioro de la salud de la ciudadanía y la reducción de los hábitats y poblaciones de las plantas criptógamas. Mediante la determinación del índice de Pureza Atmosférica (IPA) se identificaron las zonas con mayor influencia de contaminantes del aire. Parmotrema austrosinense corresponde a la especie más frecuencia; y la estación de la Normal Femenina, con IPA de 52,2196 es influenciada por los contaminantes atmosféricos; las estaciones de los Parques Santander y Semáforos son las más contaminadas (IPA 8,5333) con solo dos especies (Heterodermia albicans y Lobariaceae sp.). Se destaca la evaluación en la Reserva Forestal Protectora El Malmo con un IPA de 34,0281 y 23 especies. Los valores de IPA se agruparon en zonas de isocontaminación para ser representados cartográficamente. El uso de organismos bioindicadores es una estrategia natural y económica que permite zonificar las urbes y enfocar planes para revegetalización de ciudades, generando la disminución del impacto de contaminantes en el aire con el fin de mejorar la calidad de vida de los pobladores.

Lichens and bryophytes are useful organisms in air quality determination. In the city of Tunja (Boyacá, Colombia), is evident the lack of green areas by the increase of building, which contributes to the detriment of the atmospheric purity making unhealthy conditions to the citizens and habitats and population reduction of cryptogamic plants. Using the Index of Atmospheric Purity (IAP) we identified the greater influence air pollutants areas. Parmotrema austrosinense has the highest frequency; and the Normal Femenina station with an IAP of 52,2196 is an atmospheric pollutants influenced area; Parque Santander and Semáforos, are the most contaminated (IAP 8,5333) with only two species (Heterodermia albicans and Lobariaceae sp.). We highlight the evaluation in the Reserva Forestal Protectora El Malmo with an IAP of 34,0281 and 23 species. IAP values were grouped in isocontamination areas to be represented cartographically. The use of bioindicators organisms is a natural and economic strategy allowing us to mapping urban areas and make revegetation cities designs, generating the contaminants diminution air impact improving the citizen's life quality.

Flora terrestre de la isla Malpelo (Colombia), Pacífico Oriental Tropical / Terrestrial flora of Malpelo Island, Colombia, Eastern Tropical Pacific

Malpelo Island is located 380km off the mainland continental coast of Colombia, in the Pacific Ocean. Several geological, ecological, and zoological studies, both marine and terrestrial, have been conducted in this island. Despite some marginal comments on some publications, no single specific survey has been devoted to botany so far. In order to make a floristic inventory of the terrestrial flora of this island, three field trips were made in 2010 to collect vascular plants, mosses, and lichens, as well as data on their distribution within the island. We collected and identified 25 species of lichens, two species of vascular plants and one moss. Lichens were the most diverse group found, including records of four new genera (Endocarpon, Fuscidea, Lecanographa and Verrucaria) and 13 new species for Colombia. The high lichen richness on Malpelo might be explained by their efficient form of asexual reproduction (soredia and isidia), that may have facilitated their transport to the island by migrating birds or wind. Once on the island, it is possible that lichens persist by being chemically protected against herbivores. The great number of new generic and species records for Colombia is explained by the low number of studies in saxicolous lichens conducted so far in the country, particularly on coastal areas and remote islands. Only two species of vascular plants were collected, a grass, Paspalum sp., and a fern, Pityrogramma calomelanos, and both of them correspond to new determinations for Malpelo. A moss species previously reported but with no positive identification was collected and identified as Octoblepharum albidum. Other species previously reported, for example, some species of shrubs, were not observed. The low number of vascular plants is probably due to a combination of soil conditions and herbivory by land crabs. This study is the first complete inventory of the flora of Malpelo and is a starting and reference point for future comparisons among islands in the Eastern Tropical Pacific. Rev. Biol. Trop. 62 (1): 327-336. Epub 2014 March 01.

La isla Malpelo se encuentra en el Pacífico colombiano, a unos 380km de la costa continental. La Isla ha sido objeto de algunos estudios geológicos, ecológicos y faunísticos, tanto marinos como terrestres, pero ningún estudio estrictamente botánico. Con el fin de realizar un inventario de la flora terrestre de Malpelo, se realizaron tres salidas de campo durante el 2010, en las que se recolectaron plantas vasculares, musgos y líquenes, y se tomaron datos sobre su distribución en la Isla. El grupo más diverso correspondió a los líquenes, con 25 especies, incluidos cuatro nuevos géneros para Colombia, Endocarpon, Fuscidea, Lecanographa y Verrucaria, y 15 nuevos registros de especies para Colombia. La alta riqueza de especies de líquenes en la Isla puede deberse a la forma de reproducción asexual de estos organismos, que pudieron haber sido transportados hasta Malpelo por aves migratorias o por viento; además, pueden estar protegidos químicamente de la herbivoría por cangrejos terrestres. La gran cantidad de registros nuevos para Colombia se explica por la poca cantidad de trabajos en líquenes saxícolas en el país, sobre todo en zonas costeras e insulares. Solo se registraron dos especies de plantas vasculares, una gramínea, Paspalum sp., y un helecho, Pityrogramma calomelanos. También se recolectó una especie de musgo, Octoblepharum albidum. La escasez de plantas vasculares probablemente se deba a la combinación de condiciones de los suelos y a la herbivoría por cangrejos terrestres. El presente estudio es el primero en darle relevancia a la flora terrestre de Malpelo y constituye un punto de referencia y comparación para estudios semejantes en otras islas del Pacífico Oriental Tropical.

Effects of light and nutrients on different germination phases of the cosmopolitan moss Bryum argenteum Hedw. (Bryaceae)

The influence of light and nutrients on the different germination phases of Bryum argenteum spores was studied. The following treatments were used: distilled water and nutrient solution under light (12 h) and continuous darkness. The spores germinated when exposed to light, independent of both medium used. Under darkness, the spores swelled and became chlorophyllous. In the presence of nutrient solution, the germination occurred earlier (after two days) when compared to the distilled water (after more than three days). Nutrients were needed to complete the last germination phase in the majority of spores and to provide the protonemal growth.

Neste estudo procuramos avaliar a importância de fatores abióticos sobre a germinação de esporos e o desenvolvimento do protonema de musgos. Para isso, nós analisamos o efeito da disponibilidade de luz e nutrientes sobre diferentes fases da germinação de esporos de um musgo amplamente distribuído. Bryum argenteum geralmente apresenta muitos esporos por cápsula, e estes são amarelos devido à presença de muitos corpúsculos lipídicos. Foram usados os tratamentos: água destilada e solução nutritiva sob luz (12 h) e escuro contínuo. Os esporos mostraram-se fotoblásticos positivos, ou seja, apenas germinaram sob luz, independentemente do meio utilizado. Sob escuro os esporos apenas embeberam, tornando-se clorofilados provavelmente a partir da quebra de reservas. Em solução nutritiva a germinação ocorreu mais rapidamente (dois dias) em relação à água destilada (mais de três dias após cultivo). No entanto, os nutrientes foram necessários para completar a última fase da germinação da maioria dos esporos.

Floristic composition and diversity of Amazonian rainforest bryophytes in the state of Acre, Brazil / Composição florística e diversidade de briófitas em floresta no estado do Acre, Brasil

Bryophyte diversity in Amazonian Brazil is high, presently recorded at 514 species distributed among 36 families and 89 genera. Comparisions of species richness among the Amazonian states of Brazil suggests that the bryoflora of Acre is still underestimated, presently recorded at 106 species distributed among 33 families and 63 genera. After two field trips, the diversity increased 50 percent showing that the bryoflora is still poorly known. Collection data and comments on morphology, ecology and distribution are given for sixty-two species of bryophytes collected in the state of Acre, Brazil, which are new (fifty-two species) or interesting floristic records (ten species). Microlejeunea crenulifolia (Gottsche) Steph. and Stictolejeunea balfourdii Mitt. are new records for Brazil and fifty species are new records for Acre.

A diversidade de briófitas na região Amazônica brasileira é alta, sendo citado atualmente, 514 espécies, em 36 famílias e 89 gêneros. Comparações entre a riqueza de espécies dos estados da Amazônia brasileira sugerem que a brioflora do Acre ainda é subestimada, contando atualmente com 106 espécies, distribuídas em 33 famílias e 63 gêneros. Após duas excursões científicas, a diversidade para o estado aumentou em 50 por cento, demonstrando que a brioflora ainda é pouco conhecida. Dados sobre a morfologia, ecologia e distribuição geográfica são apresentados para sessenta e duas espécies de briófitas coletadas no estado do Acre, Brasil, as quais são registros florísticos novos (cinquenta e duas espécies) ou interessantes (dez espécies). Microlejeunea crenulifolia (Gottsche) Steph. e Stictolejeunea balfourdii Mitt. são citadas pela primeira vez para o Brasil e cinquenta espécies são novas ocorrências para o estado do Acre.

Studies on chemical constituents of Frullania muscicola / 中草药

Object To study the chemical constituents of Frullania muscicola Steph (Frullaniaceae) Methods Seven compounds were obtained from the petroleum ether extract of F muscicola by repeated chromatography over silica gel and Sephadex LH 20 Their structures were identified by analysis of their spectral data and chemical reactions Results Three steroids and four flavonoids had been isolated and their structures were identified as: stigmasterol arachidate (Ⅰ), sitosterol (Ⅱ), apigenin 7, 4′ dimethyl ethers (Ⅲ), scutellarin 6, 4′ dimethyl ethers (Ⅳ), 6 hydroxyluteolin 6, 3′ dimethyl ethers (Ⅴ), scutellarin 6 methyl ether (Ⅵ), and daucosterol (Ⅶ) Conclusion Compound I was new and the other six were obtained from this plant for the first time