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101.
Maria Rosaria Vadrucci Fabio Vignes Annita Fiocca Alberto Basset Immacolata Santarpia Gian Carlo Carrada Marina Cabrini Serena Fonda Umani 《水产资源保护:海洋与淡水生态系统》2003,13(6):489-506
- 1. The relevance of biodiversity to ecosystem processes is a major topic in ecology. Here, we analyse the relationship between biodiversity and productivity of the nano‐ and micro‐phytoplankton guilds in coastal marine ecosystems.
- 2. The patterns of variation of species richness, diversity and primary productivity (as 14C assimilation) were studied in two marine areas: a eutrophic–mesotrophic area beside the River Po delta (northern Adriatic) and an oligotrophic area around the Salento peninsula (southern Adriatic–Ionian). The study was carried out at 23 sites in the northern area and at 45 sites in the southern area. Sites were arranged on expected spatial and temporal gradients of primary productivity variation, according to distance from the coast, optical depths and seasonal period.
- 3. 167 taxa were identified in the northern area and 153 taxa in the southern area. In both areas, the taxonomic composition of the nano‐ and micro‐phytoplankton guilds exhibited greater temporal than spatial variation. The latter was much higher in the southern area than in the northern area (average dissimilarity between stations being 70.7±0.8% and 44.7±4.2% respectively).
- 4. Primary productivity varied in space and time on the gradients considered. Phytoplankton species richness and diversity exhibited significant patterns of variation in space and time; overall, these were inversely related to the primary productivity patterns in the northern area, whereas they were directly related in the southern area.
- 5. The small individual size and the high turnover rate of phytoplankton are likely to underlie the observed relationships, which emphasized a threshold response to nutrient enrichment in agreement with the ‘paradox of enrichment’. Under resource enrichment conditions, the high turnover of producers leads to hierarchical partitioning of the available resources with an increasing dominance of a few species. Therefore, the relationship observed here seems likely to be explained by the complementarity hypothesis.
102.
Ocampo Espinoza V Vázquez JE Aguilar MD Ortiz MA Alarcón GJ Rodríguez SD 《Veterinary microbiology》2006,114(1-2):34-40
In Mexico, there are no commercial alternatives for the immunoprophylaxis of bovine Anaplasmosis, a disease responsible for great economic losses. Blood derived Anaplasma marginale used for immunizing susceptible cattle has shown promising results for homologous protection and controversial results against unrelated strains. The present study examined, under controlled conditions, the cross-protective potential of an immunogen composed of blood derived A. marginale of three strains against challenge with strains not included in the immunogens. Groups 1 and 2 were immunized with blood derived Anaplasma from strains Mexico, Morelos and Yucatan, group 4 with strains Morelos, Veracruz and Yucatan, two more groups (2 and 5) of equal conditions were inoculated with an adjuvant alone. Groups 1, 4 and 5 were challenged with Mexico strain; groups 2 and 3 were challenge-inoculated with strain Veracruz; groups 3 and 5 with strains Veracruz and Mexico as controls. Only animals in group 1, immunized and challenged with strain Mexico showed adequate protection. Both groups challenged with strains not included in the immunogens developed poor protection, while all the controls had to be treated to prevent death. 相似文献
103.
Javier Puntieri Javier Grosfeld Marina Stecconi Cecilia Brion María Marta Azpilicueta Leonardo Gallo Daniel Barthélémy 《Annals of Forest Science》2007,64(8):839-844
Shoot growth and dieback were compared among progenies of nursery-grown seedlings of Nothofagus obliqua belonging to seven progenies of the same provenance (Quila-Quina, Argentina). First-year shoots consisted of one growth unit (GU) and second-year shoots of one or two GUs. The probability of development of two GU was similar for all progenies. Progenies were different in terms of shoot size, terminal bud abscission, the extent of shoot dieback after shoot extension and the node of origin of the relay shoot on the first shoot. Plants with a second-year shoot consisting of two GUs had a thicker stem and more nodes than those with single-GU shoots. The selection of N. obliqua seed trees based on architectural traits suitable for forestry development at specific sites must contemplate variability among progenies and their probabilities of successful development under different conditions. 相似文献
104.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.105.
Kovacevic Branislav Roncevic Savo Miladinovic Dragana Ivanisevic Petar Katanic Marina 《New Forests》2009,38(2):177-185
The relationship between early root and shoot formation at the beginning of the vegetation period and cutting survival on
sandy and loamy fluvisol for 14 genotypes of black poplars was analyzed. Considerable cutting mortality was observed only
within the first 80 days since planting. Intensive root formation in the first 20 days since the planting and vigorous shoot
growth and development in subsequent 20 days was observed in easy-to-root genotypes. Coefficients of correlation revealed
close relationship between early root and shoot growth and development and cutting survival of tested genotypes. The obtained
results could be used in the breeding process, as well as for the design of cultivar-adjusted nursery and plantation establishment
technology. Tested shoot characteristics, were found to be especially interesting since they could be measured rapidly, by
non-destructive means. 相似文献
106.
A new iridoid diglucoside, 10-O-(E)-p-coumaroylmelittoside (1) and a new flavone glucoside, O-(6'-O-Acetyl-)-beta-glucopyranosylchrysoeriol (2), together with four known flavone glycosides, were isolated from the aerial parts of Sideritis lanata. The structures of the new compounds were elucidated by spectroscopic methods, 2D NMR and MS. 相似文献
107.
Markus Euring Jerzy Trojanowski Marina Horstmann Alireza Kharazipour 《Wood Science and Technology》2012,46(4):699-708
In this work, the results of the enzymatic oxidation of TMP-fibers (thermomechanical pulp) and a well-structured lignin model compound, the dehydropolymer (DHP), were investigated by different 14C and 13C methods, caused by a Laccase–Mediator-System (LMS). These methods are the nuclear magnetic resonance spectroscopy (13C-NMR) with DHP (unmarked) and the determination of the 14CO2 release of 14C-marked DHP and TMP-fibers. The 13C-NMR measurements were chosen to analyze the structural changes of the LMS-treated DHP model compounds and TMP-fibers qualitatively and quantitatively. The data of 14CO2 release give an explanation of the demethylation of DHP and TMP-fibers. The effect of the LMS is shown by comparing the results in respect of DHP and TMP-fibers, which were only treated with laccase and of an inactivated LMS as the control. Comparing the results of the 13C-NMR method, in particular the use of the Mediator during the enzymatical treatment, showed significant changes in the structure of the DHP. Also, the TMP-fibers were materially influenced by the LMS. The analysis of the 14CO2 release data of the 14C-marked DHP and TMP-fibers revealed that the rate of 14CO2 increases in the 14C-2 atom as well as in the O14CH3 group within the first hour of Laccase–Mediator incubation. Therefore, the 14CO2 release from the DHP was higher than from the TMP-fibers. 相似文献
108.
Teresa P. Caams Immaculada Vias Josep Usall Rosario Torres Marina Anguera Neus Teixid 《Postharvest Biology and Technology》2008,49(1):96-106
Infection of citrus fruit by postharvest pathogens often occurs in the field prior to harvest; therefore, it could be advantageous to apply biocontrol agents before harvest, which would reduce initial infection and then remain active and control pathogens in storage and under commercial conditions. The objective of the present work was to evaluate the effectiveness of different formulations of Pantoea agglomerans applied preharvest for controlling postharvest diseases on citrus. Results confirmed the protective effect of the additive Fungicover (FC) on populations of P. agglomerans exposed to non-conducive field conditions. In general, when osmotic-adapted and lyophilised P. agglomerans cells were used in bacterial treatments, these treatments showed greater survival rates than treatments with non-osmotic-adapted or fresh cells under field conditions. However, this superiority was only found when Fungicover was also added to suspensions of bacterial treatments. Therefore, bacterial treatments with Fungicover had population levels of P. agglomerans cells 1.2 and 2.8 log CFU cm−2 higher than bacterial treatments without Fungicover during field experiments. These results allowed us to conclude that it is possible to improve environmental stress tolerance and ecological competence of P. agglomerans cells by integrating certain formulation strategies. Consequently, the improved formulation of P. agglomerans provided an effective control for orange fruit against natural postharvest pathogen infections and artificial infections of Penicillium digitatum with values of decay reduction higher than 50%. These latter results also demonstrated that it is possible to control postharvest pathogens using bacterial preharvest treatments. 相似文献
109.
Beatriz Wiebke-Strohm Annette Droste Giancarlo Pasquali Marina Borges Osorio Lauro Bücker-Neto Luciane Maria Pereira Passaglia Marta Bencke Milena Schenkel Homrich Márcia Margis-Pinheiro Maria Helena Bodanese-Zanettini 《Euphytica》2011,177(3):343-354
An Agrobacterium-mediated transformation procedure for soybean [Glycine max L. Merrill] proliferating somatic embryos is here described. The Agrobacterium tumefaciens LBA4404 strain harboring pTOK233, pCAMBIA1390-olp or pH7WG2Dwrky plasmids was used to mediate gene transfer into the plant genome. Prior to Agrobacterium inoculation, proliferative soybean embryogenic clusters were microwounded by DNA-free tungsten particle bombardment. Three
independent transformation experiments were performed. In Experiment I, 26 transgenic plants were obtained from a unique clone
of cv Bragg, while 580 plants were recovered from 105 clones of cv IAS5. In Experiment II, a single hygromycin-resistant clone
of cv BRSMG68 Vencedora was recovered and gave rise to five plants. In Experiment III, 19 plants of cv Bragg and 48 plants
of IAS5 were recovered, representing five and 14 independent transformation events, respectively. PCR and Southern analyses
confirmed the transgenes’ integration into plant genomes. Transgenic plants were fertile. They flowered, set pods and seeds.
Transgene segregation in two T1 progenies fits the Mendelian pattern (3:1 transgenic:non-transgenic plants). This is the first report of transgenic fertile
soybean plants obtained from somatic embryogenic tissues transformed by the system that combines DNA-free particle bombardment
and Agrobacterium. 相似文献
110.
Marina Antongiovanni Eduardo M. Venticinque Carlos Roberto Fonseca 《Landscape Ecology》2018,33(8):1353-1367