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101.
Robert F.H. Dekker Ana-Flora D. Vasconcelos Aneli M. Barbosa Ellen C. Giese Luzia Paccola-Meirelles 《Biotechnology letters》2001,23(24):1987-1993
A new physiological role for veratryl alcohol in fungi important in the biodegradation of the lignified plant cell wall is presented. Botryosphaeria sp., grown on starch, pectin, cellulose or xylan produced amylase, pectinase, cellulase, xylanase and laccase, whereas glucose and xylose repressed the synthesis of cellulase and xylanase, but not laccase. When cultured on each of these substrates in the presence of veratryl alcohol, laccase activity increased but the activities of amylase, pectinase, cellulase and xylanase significantly decreased. Basal medium containing softwood kraft lignin in the presence of veratryl alcohol induced laccases above constitutive levels. Ethyl alcohol also stimulated laccase production. 相似文献
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103.
Alan N. Costa Heraldo L. Vasconcelos Ernane H.M. Vieira‐Neto Emilio M. Bruna 《Ecological Entomology》2019,44(2):227-238
1. Generalist herbivores feed on a wide and diverse set of species, but fine‐scale foraging patterns may be affected by the interplay between the quality, quantity and spatial distribution of host plants. 2. The foraging patterns of a prevalent Neotropical herbivore, the leaf‐cutter ant Atta laevigata, in the Brazilian Cerrado savannas were examined in order to determine if patterns observed are in concert with central‐place foraging predictions. 3. The results showed that A. laevigata acts as a polyphagous but highly selective herbivore, with ant attacks often resulting in partial defoliation of less‐preferred species and full defoliation of preferred ones. It was found, for the first time, that there is a strong and positive relationship between the relative attack frequency on plants from preferred species and foraging distance to the nest. This suggests a balance between the quality of plant resources harvested and costs involved in their transportation. It was also observed that colonies focused their harvest on preferred species in months with low availability of young leaves. Consequently, high herbivory rate was more frequent in plants attacked far away from the nest and in dry months. 4. These assessments highlight the fact that Atta colonies may become more selective as foraging distance to the nest increases and in response to fluctuations in the availability of palatable resources throughout the year. The results also show some dissimilarities in the foraging behaviours of A. laevigata when compared with other locations, suggesting that widely distributed herbivores may modify foraging strategies across their geographic range. 相似文献
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107.
L. S. Catenacci L. C. Martins K. M. De Vleeschouwer C. R. Cassano L. C. Oliveira G. Canale S. L. Deem J. S. Tello P. Parker P. F. C. Vasconcelos E. S. Travassos da Rosa 《EcoHealth》2018,15(4):777-791
From 2006 through 2014, we conducted seroepidemiological surveys on non-human primates and sloths to investigate the possible circulation of arboviruses in Bahia Atlantic Forest, Brazil. We collected a total of 196 samples from 103 Leontopithecus chrysomelas, 7 Sapajus xanthosternos, 22 Bradypus torquatus and 7 Bradypus variegatus. Serum samples were tested using neutralization test and hemagglutination inhibition test to detect total antibodies against 26 different arboviruses. The overall prevalence of arboviruses was 36.6% (51/139), with the genus Flavivirus having the highest prevalence (33.1%; 46/139), followed by Phlebovirus (5.0%; 7/139), Orthobunyavirus (4.3%; 6/139) and Alphavirus (0.7%; 1/139). Monotypic reactions suggest that the wild animals were exposed naturally to at least twelve arboviruses. Added results from the neutralization test, animals were exposed to thirteen arboviruses. Most of these viruses are maintained in transmission cycles independent of human hosts, although antibodies against dengue virus serotypes 1, 2 and 3 were found in this study. To our knowledge, this is the first study reporting exposure to arboviruses in L. chrysomelas, S. xanthosternos and B. torquatus. Our results also highlight that the Southern Bahia Atlantic Forest has a variety of vertebrate hosts and potential vectors, which may support the emergence or re-emergence of arboviruses, including those pathogenic to humans. 相似文献
108.
Xavier Arnan Alan N. Andersen Heloise Gibb Catherine L. Parr Nathan J. Sanders Robert R. Dunn Elena Angulo Fabricio B. Baccaro Tom R. Bishop Raphaël Boulay Cristina Castracani Xim Cerdá Israel Del Toro Thibaut Delsinne David A. Donoso Emilie K. Elten Tom M. Fayle Matthew C. Fitzpatrick Crisanto Gómez Donato A. Grasso Blair F. Grossman Benoit Guénard Nihara Gunawardene Brian Heterick Benjamin D. Hoffmann Milan Janda Clinton N. Jenkins Petr Klimes Lori Lach Thomas Laeger Maurice Leponce Andrea Lucky Jonathan Majer Sean Menke Dirk Mezger Alessandra Mori Jimmy Moses Thinandavha Caswell Munyai Omid Paknia Martin Pfeiffer Stacy M. Philpott Jorge L.P. Souza Melanie Tista Heraldo L. Vasconcelos Javier Retana 《Global Change Biology》2018,24(10):4614-4625
The relationship between levels of dominance and species richness is highly contentious, especially in ant communities. The dominance‐impoverishment rule states that high levels of dominance only occur in species‐poor communities, but there appear to be many cases of high levels of dominance in highly diverse communities. The extent to which dominant species limit local richness through competitive exclusion remains unclear, but such exclusion appears more apparent for non‐native rather than native dominant species. Here we perform the first global analysis of the relationship between behavioral dominance and species richness. We used data from 1,293 local assemblages of ground‐dwelling ants distributed across five continents to document the generality of the dominance‐impoverishment rule, and to identify the biotic and abiotic conditions under which it does and does not apply. We found that the behavioral dominance–diversity relationship varies greatly, and depends on whether dominant species are native or non‐native, whether dominance is considered as occurrence or relative abundance, and on variation in mean annual temperature. There were declines in diversity with increasing dominance in invaded communities, but diversity increased with increasing dominance in native communities. These patterns occur along the global temperature gradient. However, positive and negative relationships are strongest in the hottest sites. We also found that climate regulates the degree of behavioral dominance, but differently from how it shapes species richness. Our findings imply that, despite strong competitive interactions among ants, competitive exclusion is not a major driver of local richness in native ant communities. Although the dominance‐impoverishment rule applies to invaded communities, we propose an alternative dominance‐diversification rule for native communities. 相似文献
109.
Antonio C. L. da Costa Lucy Rowland Rafael S. Oliveira Alex A. R. Oliveira Oliver J. Binks Yann Salmon Steel S. Vasconcelos João A. S. Junior Leandro V. Ferreira Rafael Poyatos Maurizio Mencuccini Patrick Meir 《Global Change Biology》2018,24(1):249-258
Transpiration from the Amazon rainforest generates an essential water source at a global and local scale. However, changes in rainforest function with climate change can disrupt this process, causing significant reductions in precipitation across Amazonia, and potentially at a global scale. We report the only study of forest transpiration following a long‐term (>10 year) experimental drought treatment in Amazonian forest. After 15 years of receiving half the normal rainfall, drought‐related tree mortality caused total forest transpiration to decrease by 30%. However, the surviving droughted trees maintained or increased transpiration because of reduced competition for water and increased light availability, which is consistent with increased growth rates. Consequently, the amount of water supplied as rainfall reaching the soil and directly recycled as transpiration increased to 100%. This value was 25% greater than for adjacent nondroughted forest. If these drought conditions were accompanied by a modest increase in temperature (e.g., 1.5°C), water demand would exceed supply, making the forest more prone to increased tree mortality. 相似文献
110.
M. C. P. Amorim † R. O. Vasconcelos J. F. Marques ‡ F. Almada § 《Journal of fish biology》2006,69(6):1892-1899
Seasonal variation of sound production, which includes boatwhistles, grunts, croaks and double croaks, was studied in the Lusitanian toadfish Halobatrachus didactylus . Boatwhistles were emitted during the mating season in contrast with the other sound types, which were emitted all year round. 相似文献