Biotopes of bromeliads observed in three national parks situated in south-eastern Brazil are described. Epiphytic and terres - trial species from tropical rainforests and cloud forests, together referred to as Mata atlântica, are pictured. An interesting story about a very popular cultivated variety Neo - regelia cv. Fireball is also mentioned. and Miloslav Studnička.
Článek přibližuje botanickou exkurzi do Brazílie na horu Corcovado (710 m n. m.), nacházející se u pobřeží Atlantského oceánu, na vrcholu se sochou Krista Vykupitele (Cristo Redentor). Území leží v národním parku Tijuca, který byl zřízen na ochranu tropického deštného lesa, zde nazývaného mata atlântica (atlantský les). Autor představuje některé významné skupiny zdejší flóry, vybrané endemické taxony či rostliny se zajímavou životní strategií., This article presents a botanical excursion up Mount Corcovado (710 m a. s. l.) on the Atlantic coast of Brazil, with the statue of Christ the Redeemer (Cristo Redentor) at the top. The territory belongs to the Tijuca National Park, established to protect the tropical rain forest - called mata atlântica (Atlantic forest). Several important groups of local flora, selected endemic taxons and also plants with interesting life strategies are presented here., and Miloslav Studnička.
Z geobotanického hlediska je popsána subalpinská a alpinská vegetace v horách jihovýchodní Brazílie. Přirozené požáry tam ovlivňují strukturu rostlinných společenstev. Jsou zmíněny zajímavé životní způsoby, jako je mykorhiza, hemiparazitismus a masožravost. Jedním z nejzajímavějších fenomenů je symbióza mezi masožravou rostlinou Utricularia cornigera (bublinatkou růžkatou) a růžicovitými rostlinami Vriesea atra nebo Eryngium fluminense. Je diskutováno o problému srovnávání popsané brazilské vegetace a páramos v Andách. Pojem "brazilská páromos" je odmítnut., The subalpine and alpine vegetation in mountains of south-eastern Brazil is described from the botanical point of view. Natural fires affect the structure of plant communities there. Interesting life strategies, such as mycorrhiza, hemiparasitism and carnivory, are mentioned. One of the most interesting is the symbiosis between carnivorous Utricularia cornigera and rosette plants of Vriesea atra or Eryngium fluminense. Brazilian vegetation and páramos in the Andes are compared., and Miloslav Studnička.
Brazilian native meliponines are currently threatened by increased human impacts. The assessment of their genetic variation by microsatellite DNA markers can assist in the conservation of populations and help in the planning and establishment of efficient management strategies. The purpose of this study was to develop the first set of microsatellite markers for Melipona fasciculata, selected from partial genome assembly of Illumina paired-end reads. Primer pairs were designed for each detected locus at their flanking regions. Bee samples were genotyped from two different populations of Northeastern Brazil for marker characterization and validation. A total of 17 microsatellite loci displayed polymorphism. Mean HE and HO heterozygosities were 0.453 and 0.536, respectively. PIC across all loci ranged from 0.108 to 0.714. A genetic diversity analysis revealed high values for population differentiation estimates (FST = 0.194, RST = 0.230, and Dest = 0.162) within the investigated region. PCoA and Bayesian clustering showed a separation of the species into two distinct clusters. These microsatellite markers have demonstrated strong potential for population-level genetic studies. Moreover, the preliminary analysis of the genetic diversity in M. fasciculata provides provisional evidence of significant population differentiation between the two studied populations., Geice Ribeiro Da Silva, Isis Gomes De Brito Souza, Fabia De Mello Pereira, Bruno De Almeida Souza, Maria Teresa Do Rego Lopes, Paul Bentzen, Fabio Mendonça Diniz., and Obsahuje bibliografii
Light is a limiting factor in plant establishment and growth in the understory of forests. In this paper, we assessed acclimation capacity of Siparuna guianensis, an early secondary successional species. We used seedlings and saplings in three regeneration areas with different irradiance regimes to determine the traits that confer photoplasticity. We examined whether these traits differ at different developmental stages. Anatomical characteristics, photochemical efficiency, photosynthetic capacity, and growth were analyzed. Multivariate component analysis revealed the formation of six clusters: three for seedlings (one for each regeneration area) and three for saplings (following the same pattern of seedlings, considering the area). Increased irradiance favored photosynthetic performance, independently of the developmental stage. The same trend was observed for most data on chlorophyll (Chl) a fluorescence and the ratios of net photosynthetic rate/intercellular CO2 concentration (PN/Ci) and PN/PPFD. No parameter indicated photoinhibition stress. The CO2- and light-response curve data indicated that seedlings were already acclimated to tolerate variation in irradiance. Anatomical adaptations, such as thickness of leaf blade and of adaxial cuticle, were observed in individuals growing in areas with higher irradiation. Thinning of spongy parenchyma and higher investment into a plant height were observed in seedlings, possibly due to the vertical stratification of CO2 and light in the understory; because light is a more limiting resource than CO2 in the lower stratum of the forest. Photoplasticity in S. guianensis is associated with a set of morphological, anatomical, photochemical, and biochemical traits, whereas biochemical performance is best acclimated to variation in irradiance. These traits differed in seedlings and saplings but they were modulated mainly by irradiance in both developmental stages., T. O. Vieira, M. S. O. Degli-Esposti, G. M. Souza, G. R. Rabelo, M. Da Cunha, A. P. Vitória., and Obsahuje bibliografii
To analyze acclimation of Euterpe edulis seedlings to changes in light availability, we transferred three-year-old seedlings cultivated for six months under natural shade understory [= 1.3 mol(photon) m-2 d-1] to a forest gap [= 25.0 mol(photon) m-2 d-1]. After the transfer, changes in chlorophyll fluorescence and leaf gas-exchange parameters, as well as in the light-response curves of photosynthesis and photosynthetic induction parameters, were analyzed during the following 110 days. Simultaneously measured photosynthetic characteristics in the shaded seedlings grown in understory served as the control. Despite the fact that the understory seedlings were under suboptimal conditions to achieve their light-saturated net photosynthetic rate (PNmax), light-response curves and photosynthetic induction parameters indicated that the species had the low respiration rate and a fast opening of stomata in response to the intermittent occurrence of sunflecks, which exerted a feed-forward stimulation on PNmax. Sudden exposure to high light induced photoinhibition during the first week after the transfer of seedlings to gap, as it was shown by the abrupt decline of the maximal quantum yield of PSII photochemistry (Fv/Fm). The photoinhibition showed the time-dependent dynamics, as the Fv/Fm of the seedlings transferred to the forest gap recovered completely after 110 days. Furthermore, the net photosynthetic rate increased 3.5-fold in relation to priorexposure values. In summary, these data indicated that more than 21 days was required for the shade-acclimated seedlings to recover from photoinhibition and to relax induction photosynthetic limitations following the sudden exposure to high light. Moreover, the species responded very quickly to light availability; it highlights the importance of sunflecks to understory seedlings., A. O. Lavinsky, F. P. Gomes, M. S. Mielke, S. França., and Obsahuje bibliografii
Knowledge of the patterns in the spatial distribution of species provides valuable information about the factors (resources and environment) that regulate the use of space by animals. Typically, the distribution of litter-dwelling scorpions in Atlantic forests is correlated with the structure of their microhabitats, although to better understand their natural history more studies on the patterns in their use of space are required. Therefore, we investigated the effect of rainfall on the patterns in the spatial distributions and population densities of two sympatric species of scorpion, Tityus (Archaeotityus) pusillus Pocock 1893 and Ananteris mauryi Lourenço 1982 in a fragment of Atlantic Forest in Brazil. The study was carried out during the dry (September) and rainy (June) months. We collected 501 individuals (268 T. (A.) pusillus and 233 A. mauryi) by actively searching at night using UV lanterns. We found that the spatial distribution and population density of T. (A.) pusillus, but not A. mauryi, were significantly affected by rainfall, with T. (A.) pusillus individuals showing a clumped pattern during the rainy month and random distribution in the dry month. We also found a different response in the population densities of the two species, with T. (A.) pusillus but not A. mauryi being affected by rainfall. Our results indicate that, although co-habiting in leaf litter, these species respond differently to rainfall, which affects their spatial distribution and abundance in this habitat., Gabriela Cavalcanti Silva de Gusmão Santos, Welton Dionisio-Da-Silva, João Pedro Souza-Alves, Cleide Maria Ribeiro de Albuquerque, André Felipe de Araujo Lira., and Obsahuje bibliografii
High irradiance promotes decreases in the quantum yield in plants, which reduce the photosynthetic rate. The excess of light in combination with water deficit can intensify the response of plants to stress, especially in species susceptible to those factors. The aim of the present study was to characterize the photosynthetic activity of young jatobá-do-cerrado (Hymenaea stigonocarpa Mart. ex Hayne) trees under different irradiance conditions, both alone and/or in combination with water deficit. Four irradiances [45, 230, 510, and 1,700 μmol(photon) m-2 s-1] and two levels of water in soil (90% and 50% of field capacity) were used. Gas exchange, water potential, and chlorophyll a fluorescence were measured. The highest rates of photosynthesis were observed under irradiances of 230 and 510 μmol(photon) m-2 s-1. Irradiance of 1,700 μmol(photon) m-2 s-1 led to the photoinhibition of photosynthesis, as indicated by a reduced maximum quantum yield of PSII, effective quantum yield ratio, and electron transport rate, as well as higher nonphotochemical quenching. The most stressful to young H. stigonocarpa plants was high irradiance, while water deficit did not intensify the response to light stress., A. C. Costa, S. L. Rezende-Silva, C. A. Megguer, L. M. F. Moura, M. Rosa, A. A. Silva., and Obsahuje bibliografii
Tropical savanna ecosystems are extremely diverse and important for global carbon storage. In the state of Mato Grosso, tropical savanna (locally known as the Cerrado), turns from well-drained, upland areas into seasonally flooded areas within the Pantanal; however, the Cerrado and the Pantanal share many common tree species, such as Vochysia divergens, a flood-adapted tree native to the Amazon Basin, and Curatella americana, a tree, adapted native to the welldrained the Cerrado. We measured the photosynthetic light response of these species in the the Cerrado and the Pantanal over a 1-year period to determine how these species physiologically adjust to these hydrologically distinct habitats. We hypothesized that neither species would experience a significant decline in maximum, light-saturated photosynthetic rate (Pmax) in their naturalized habitat. Physiological performance of each species was generally higher in the habitat that they were adapted to; however, our data indicated that both species have broad tolerance for seasonal variations in hydrology, allowing them to tolerate seasonal drought during the dry season in the Cerrado, and seasonal flooding during the wet season in the Pantanal. In V. divergens, flexible water-use efficiency, higher specific leaf area (SLA), and a greater ability to adjust mass-based Pmax (Pmax,m) to variations in leaf N and P concentration appeared to be key traits for withstanding prolonged drought in the Cerrado. In C. americana, increases in SLA and higher nutrient-use efficiency appeared to be important in maintaining high rates of Pmax,m in the seasonally flooded Pantanal. Flexibility in physiology and resource-use efficiency may allow these species to survive and persist in habitats with broadly differing hydrology., H. J. Dalmagro, F. de A. Lobo, G. L. Vourlitis, Â. C. Dalmolin, M. Z. Antunes Jr., C. E. R. Ortíz, J. de S. Nogueira., and Obsahuje bibliografii