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941.
Maria Rosaria Barone Lumaga Mario Coiro Elisabeth Truernit Boglrka Erdei Paolo De Luca 《Botanical journal of the Linnean Society. Linnean Society of London》2015,179(2):236-254
The genus Dioon occupies an important phylogenetic position as sister to the other Zamiaceae. However, its epidermal morphology is still poorly known. We employed scanning and transmission electron microscopy, confocal microscopy and light microscopy to examine the epidermal and cuticular morphology of 12 of the 14 currently recognized species of Dioon, examining cultivated plants and herbarium specimens. Epidermal characters separate Dioon quite clearly from the other genera of the cycads. Within the genus, the major subgroups can be distinguished by their epidermal morphology. Some characters, such as the degree of stomatal protection, reflect ecological specializations in species within the subgroups. Several epidermal characters of the crown group Dioon seem to be absent in the Cenozoic fossils usually associated with the genus, which have been used as calibrations in many recent molecular dating analyses. The presence of similar characters in a Mesozoic fossil adapted to volcanic stress offers a new key in the interpretation of Dioon evolution. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 236–254. 相似文献
942.
Satellite‐derived NDVI,LST, and climatic factors driving the distribution and abundance of Anopheles mosquitoes in a former malarious area in northwest Argentina
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![点击此处可从《Journal of vector ecology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
María Julia Dantur Juri Elizabet Estallo Walter Almirón Mirta Santana Paolo Sartor Mario Lamfri Mario Zaidenberg 《Journal of vector ecology》2015,40(1):36-45
Distribution and abundance of disease vectors are directly related to climatic conditions and environmental changes. Remote sensing data have been used for monitoring environmental conditions influencing spatial patterns of vector‐borne diseases. The aim of this study was to analyze the effect of the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) obtained from the Moderate Resolution Imaging Spectroradiometer (MODIS), and climatic factors (temperature, humidity, wind velocity, and accumulated rainfall) on the distribution and abundance of Anopheles species in northwestern Argentina using Poisson regression analyses. Samples were collected from December, 2001 to December, 2005 at three localities, Aguas Blancas, El Oculto and San Ramón de la Nueva Orán. We collected 11,206 adult Anopheles species, with the major abundance observed at El Oculto (59.11%), followed by Aguas Blancas (22.10%) and San Ramón de la Nueva Orán (18.79%). Anopheles pseudopunctipennis was the most abundant species at El Oculto, Anopheles argyritarsis predominated in Aguas Blancas, and Anopheles strodei in San Ramón de la Nueva Orán. Samples were collected throughout the sampling period, with the highest peaks during the spring seasons. LST and mean temperature appear to be the most important variables determining the distribution patterns and major abundance of An. pseudopunctipennis and An. argyritarsis within malarious areas. 相似文献
943.
Natalia Kirichenko Peter Huemer Helmut Deutsch Paolo Triberti Rodolphe Rougerie Carlos Lopez-Vaamonde 《ZooKeys》2015,(473):157-176
Europe has one of the best-known Lepidopteran faunas in the world, yet many species are still being discovered, especially in groups of small moths. Here we describe a new gracillariid species from the south-eastern Alps, Callisto
basistrigella Huemer, Deutsch & Triberti, sp. n. It shows differences from its sister species Callisto
coffeella in morphology, the barcode region of the cytochrome c oxidase I gene and the nuclear gene histone H3. Both Callisto
basistrigella and Callisto
coffeella can co-occur in sympatry without evidence of admixture. Two Callisto
basistrigella specimens show evidence of introgression. We highlight the importance of an integrative approach to delimit species, combining morphological and ecological data with mitochondrial and nuclear sequence data. Furthermore, in connection with this study, Ornix
blandella Müller-Rutz, 1920, syn. n. is synonymized with Callisto
coffeella (Zetterstedt, 1839). 相似文献
944.
The Contribution of Agriculture,Forestry and other Land Use activities to Global Warming, 1990–2012
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![点击此处可从《Global Change Biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Francesco N. Tubiello Mirella Salvatore Alessandro F. Ferrara Jo House Sandro Federici Simone Rossi Riccardo Biancalani Rocio D. Condor Golec Heather Jacobs Alessandro Flammini Paolo Prosperi Paola Cardenas‐Galindo Josef Schmidhuber Maria J. Sanz Sanchez Nalin Srivastava Pete Smith 《Global Change Biology》2015,21(7):2655-2660
We refine the information available through the IPCC AR5 with regard to recent trends in global GHG emissions from agriculture, forestry and other land uses (AFOLU), including global emission updates to 2012. Using all three available AFOLU datasets employed for analysis in the IPCC AR5, rather than just one as done in the IPCC AR5 WGIII Summary for Policy Makers, our analyses point to a down‐revision of global AFOLU shares of total anthropogenic emissions, while providing important additional information on subsectoral trends. Our findings confirm that the share of AFOLU emissions to the anthropogenic total declined over time. They indicate a decadal average of 28.7 ± 1.5% in the 1990s and 23.6 ± 2.1% in the 2000s and an annual value of 21.2 ± 1.5% in 2010. The IPCC AR5 had indicated a 24% share in 2010. In contrast to previous decades, when emissions from land use (land use, land use change and forestry, including deforestation) were significantly larger than those from agriculture (crop and livestock production), in 2010 agriculture was the larger component, contributing 11.2 ± 0.4% of total GHG emissions, compared to 10.0 ± 1.2% of the land use sector. Deforestation was responsible for only 8% of total anthropogenic emissions in 2010, compared to 12% in the 1990s. Since 2010, the last year assessed by the IPCC AR5, new FAO estimates indicate that land use emissions have remained stable, at about 4.8 Gt CO2 eq yr?1 in 2012. Emissions minus removals have also remained stable, at 3.2 Gt CO2 eq yr?1 in 2012. By contrast, agriculture emissions have continued to grow, at roughly 1% annually, and remained larger than the land use sector, reaching 5.4 Gt CO2 eq yr?1 in 2012. These results are useful to further inform the current climate policy debate on land use, suggesting that more efforts and resources should be directed to further explore options for mitigation in agriculture, much in line with the large efforts devoted to REDD+ in the past decade. 相似文献
945.
946.
947.
Predicting the impact of increasing carbon dioxide concentration and temperature on seed germination and seedling establishment of African grasses in Brazilian Cerrado
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Ana Paula de Faria Geraldo Wilson Fernandes Marcel Giovanni Costa França 《Austral ecology》2015,40(8):962-973
Global climate changes and biological invasions are environmental disturbances that may interact synergistically, causing loss of biodiversity. As the early stages of development are the most sensitive and easily affected by these constraints, this study investigated the effects of increased carbon dioxide (CO2) and temperature, as forecasted for 2100, on seed germination and early development of three species of invasive African grasses that have gradually replaced landscapes of the Brazilian Cerrado biome. It was observed that these parameters affected percentage and rate of germination in Urochloa brizantha, rate of germination and mean germination time in Urochloa decumbens and accelerated autotrophy acquisition in U. brizantha, U. decumbens and Megathyrsus maximus. Regarding root elongation, all species showed changes in total length, absolute and relative growth rate, but at different stages of development or time intervals, with increased temperature being more significant than increased CO2, probably due to seed reserves still being the main carbon sources at this stage. Taken together, the results indicate that the effects of CO2 and increased temperature are species specific and highlight the greatest potential of U. brizantha to germinate, and of U. decumbens for seedling establishment under these environmental changes. 相似文献
948.
Area‐wide monitoring of potato tuberworm (Phthorimaea operculella) by pheromone trapping in Northern Italy: phenology,spatial distribution and relationships between catches and tuber damage
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![点击此处可从《Agricultural and Forest Entomology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Antonio Masetti Alda Butturini Alberto Lanzoni Valentino De Luigi Giovanni Burgio 《Agricultural and Forest Entomology》2015,17(2):138-145
949.
Cyclic lipopeptides from Bacillus subtilis activate distinct patterns of defence responses in grapevine
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![点击此处可从《Molecular Plant Pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Giovanni Farace Olivier Fernandez Lucile Jacquens François Coutte François Krier Philippe Jacques Christophe Clément Essaid Ait Barka Cédric Jacquard Stéphan Dorey 《Molecular Plant Pathology》2015,16(2):177-187
Non‐self‐recognition of microorganisms partly relies on the perception of microbe‐associated molecular patterns (MAMPs) and leads to the activation of an innate immune response. Bacillus subtilis produces three main families of cyclic lipopeptides (LPs), namely surfactins, iturins and fengycins. Although LPs are involved in induced systemic resistance (ISR) activation, little is known about defence responses induced by these molecules and their involvement in local resistance to fungi. Here, we showed that purified surfactin, mycosubtilin (iturin family) and plipastatin (fengycin family) are perceived by grapevine plant cells. Although surfactin and mycosubtilin stimulated grapevine innate immune responses, they differentially activated early signalling pathways and defence gene expression. By contrast, plipastatin perception by grapevine cells only resulted in early signalling activation. Gene expression analysis suggested that mycosubtilin activated salicylic acid (SA) and jasmonic acid (JA) signalling pathways, whereas surfactin mainly induced an SA‐regulated response. Although mycosubtilin and plipastatin displayed direct antifungal activity, only surfactin and mycosubtilin treatments resulted in a local long‐lasting enhanced tolerance to the necrotrophic fungus Botrytis cinerea in grapevine leaves. Moreover, challenge with specific strains overproducing surfactin and mycosubtilin led to a slightly enhanced stimulation of the defence response compared with the LP‐non‐producing strain of B. subtilis. Altogether, our results provide the first comprehensive view of the involvement of LPs from B. subtilis in grapevine plant defence and local resistance against the necrotrophic pathogen Bo. cinerea. Moreover, this work is the first to highlight the ability of mycosubtilin to trigger an immune response in plants. 相似文献
950.
?zgün Babur Mithat G?nen Bülent Arman Aksoy Nikolaus Schultz Giovanni Ciriello Chris Sander Emek Demir 《Genome biology》2015,16(1)
We present a novel method for the identification of sets of mutually exclusive gene alterations in a given set of genomic profiles. We scan the groups of genes with a common downstream effect on the signaling network, using a mutual exclusivity criterion that ensures that each gene in the group significantly contributes to the mutual exclusivity pattern. We test the method on all available TCGA cancer genomics datasets, and detect multiple previously unreported alterations that show significant mutual exclusivity and are likely to be driver events.