Artificial decrease of leaf area affects inflorescence quality but not floral size in Antirrhinum majus     

Almundena Bayo-Canha  Luciana Delgado-Benarroch  Julia Weiss  Marcos Egea-Cortines 《Scientia Horticulturae》2007

We have studied the effect of artificial modification of leaf area on inflorescence and floral quality in Antirrhinum majus. We used two treatments where we clipped all the leaves except the first three pairs of true leaves, or we cut every leaf visible by the time the plant had six leaf pairs. Decreased leaf area caused a decrease in stem elongation that could be traced back to a decrease in internode elongation. Leaves left on the plant increased their size beyond control. Inflorescence quality was strongly affected since total floral number showed a strong decrease with reduced leaf area. In contrast, floral size hardly changed. Breeding programs in Antirrhinum should take into account growth conditions affecting leaf area when searching for changes in inflorescence quality while floral size can be screened independently of this factor.  相似文献   

Plants,small mammals,and the hierarchical landscape classifications of Patagonia     

Monjeau  J. Adrian  Birney  Elmer C.  Ghermandi  Luciana  Sikes  Robert S.  Margutti  Laura  Phillips  Carleton J. 《Landscape Ecology》1998,13(5):285-306

Assemblages of plants were studied at 14 sites in northern Patagonia corresponding to localities at which we (Monjeau et al. 1997) earlier studied the relationship between small mammal assemblages and landscape classifications. This allowed us to test predictions that both plants and small mammals correspond to the more inclusive hierarchical landscape divisions but that plants track better than small mammals the less inclusive divisions. Species presence or absence of plants at each locality was used in a series of multivariate analyses and compared by correlation analysis with those generated from small mammal species data. Assemblages of both plants and small mammals corresponded to the upper divisions, which are based on climatic and geomorphological features, but small mammal assemblages did not correspond to the lower divisions of the landscape classifications. Three factors are considered as explanations for the observed differences between plants and small mammals: a) small mammal habitat is determined more by plant growth form than by plant species; b) trophic level differences between the two groups; and c) species pool size affects the resolution of microhabitat correspondence. Our data indicate that both plant assemblages and small mammal assemblages respond to climatic and geomorphological features, which is in contrast to the paradigm that mammal assemblages simply follow plant assemblages. We also attempted to reconcile classification systems in Patagonia by proposing a nomenclatural system based on a hierarchical classification. In the system proposed, ecoregion is the lowest division small mammal assemblages can recognize in Patagonia. Finally, we conclude that the hierarchical nature of landscapes based on a holistic view of environments reflects real entities that are not just the perceptions of landscape ecologists.  相似文献   

Reproductive and productive performances of Santa Inês ewes submitted to breeding in different periods of the Amazonian humid tropical climate     

Felipe Nogueira Soares  Maria Emilia Franco Oliveira  Luciana Cristina Padilha-Nakaghi  Luís Guilherme de Oliveira  Marcus Antônio Rossi Feliciano  Felipe Brener Bezerra de Oliveira  Pedro Paulo Maia Teixeira  Wilter Ricardo Russiano Vicente  Cristian Faturi  Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471

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Lipoperoxidation and cyclooxygenases 1 and 2 inhibitory compounds from Iryanthera juruensis     

Silva DH  Zhang Y  Santos LA  Bolzani VS  Nair MG 《Journal of agricultural and food chemistry》2007,55(7):2569-2574

Plants from Iryanthera genus have been traditionally used as food supplements by South American Indians. The MeOH extract of leaves of Iryanthera juruensis, one of the plants endemic to the Amazon region and consumed in Brazil, and the hexane extract from its seeds inhibited lipid peroxidation (LPO) and cyclooxygenase (COX-1 and -2)) enzymes in in vitro assays. Further analyses of these extracts yielded 5-deoxyflavones (1-5) from the leaf extract and sargachromenol (6), sargaquinoic acid (7), a novel juruenolic acid (8), omega-arylalkanoic acids (9a-c), and the lignan guaiacin (10) from the seed extract. Compounds 3-5 inhibited LPO by 86%, 77%, and 88% at 10 ppm, respectively, and compounds 6 and 9a-c showed inhibition at 76% and 78% at 100 ppm, respectively. However, compounds 7 and 8 were inactive and lignan 10 exhibited LPO inhibitory activity by 99% at 100 ppm compared to commercial antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and vitamin E. The flavones 1-5 also inhibited COX-1 and -2 enzymes by 50-65% at 100 ppm. Compound 6 showed high but nonselective inhibition of COX-1 and COX-2 enzymes, when compared to aspirin and Celebrex, a nonsteroidal anti-inflammatory drug (NSAID). Compounds 7 and 10 inhibited COX-1 by 60% and 65% and COX-2 by 37% and 18%, respectively, whereas compounds 8 and 9a-c showed little or no activity against these enzymes.  相似文献   

Spectrophotometric evidence for the solubilization site of betalain pigments in membrane biomimetic systems     

Liveri ML  Sciascia L  Lombardo R  Tesoriere L  Passante E  Livrea MA 《Journal of agricultural and food chemistry》2007,55(8):2836-2840

The solubilization site of two betalain pigments, namely, betanin and indicaxantin, into l-alpha-dipalmitoyl-phosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) vesicles was investigated by a spectrophotometric study. Pigment absorbance was monitored by varying phospholipid concentration, at a constant temperature that was varied in a range including the main phase transition temperature (Tm) of the relevant phospholipid bilayer. Maximum betanin absorption increased with the increase of DPPC concentration within the entire temperature range, reaching a plateau. The binding constant (Kb) of the pigment, calculated according to a pseudo-two-phase model, varied with the temperature, indicating that betanin is located at the hydrophobic interior of the bilayer. Other measurements of binding of betanin to DMPC and of indicaxanthin to either DPPC or DMPC vesicles ruled out that these compounds were solubilized in the hydrophobic interior of these bilayers.  相似文献   

Cholecystocutaneous fistula containing multiple gallstones in a dog     

Martina Fabbi  Antonella Volta  Fausto Quintavalla  Elena Zubin  Sabrina Manfredi  Filippo M. Martini  Luciana Mantovani  Mario Tribaudino  Giacomo Gnudi 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(12):1163-1166

A 7-year-old dog was presented with a history of an open lesion on the right thoracic wall, discharging honey-like fluid and small stones. Ultrasonography and computed tomographic fistulography identified a cholecystocutaneous fistula; cholecystectomy was curative. Veterinarians should consider this disease in patients with long-term discharging lesions on the right thoracic or abdominal wall.  相似文献   

Acquisition capability of the grapevine Flavescence dorée by the leafhopper vector Scaphoideus titanus Ball correlates with phytoplasma titre in the source plant     

Luciana Galetto  Dimitrios Miliordos  Chiara Roggia  Mahnaz Rashidi  Dario Sacco  Cristina Marzachì  Domenico Bosco 《Journal of pest science》2014,87(4):671-679

Flavescence dorée (FD) is one of the most economically important grapevine diseases in Southern Europe, and it is associated with phytoplasmas, phloem-limited wall-less bacteria. Recovery from disease naturally occurs in infected grapevines during the following seasons after infection. The capability of the leafhopper vector Scaphoideus titanus to acquire FD phytoplasma (FDP) from recovered and infected grapevines of Barbera and Nebbiolo varieties was investigated in North-western Italy vineyards monitored from 2007 to 2011. Pathogen concentration was quantified by real-time PCR in FDP-infected grapevines and broad beans, also used as source plants under controlled conditions, to correlate acquisition capabilities and phytoplasma titre in source plants. S. titanus acquired FDP from infected, but not from recovered, grapevines. FDP titre was higher in Barbera than in Nebbiolo and higher in summer than in spring, and acquisition efficiency and pathogen titre in source plants were positively correlated, both in field and laboratory conditions. Recovered plants do not represent a source of inoculum for the vector and therefore do not contribute to FDP spread. The inability of recovered plants to serve as FDP acquisition sources for the vector as well as the effect of the season and of the two grapevine varieties on the FDP acquisition efficiency are relevant results to re-design disease management practices, especially since insecticide treatments against the vector are not fully effective, and newly designed successful control strategies are required.  相似文献   

Benthic microbial indicators of fish farm impact in a coastal area of the Tyrrhenian Sea     

Tiziana La Rosa  Simone Mirto  Antonio Mazzola  Teresa Luciana Maugeri 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):153-167

We studied the impact of organic loads due to the biodeposition of a fish farm in a non-impacted coastal area of the Tyrrhenian Sea (Western Mediterranean). Sediment chemistry and benthic microbial community were investigated from July 1997 to February 1998 on monthly basis at two stations: one was located under the fish farm, while the second was about 1 km away, and served as a reference site. The presence of the cage induced rapid changes in the benthic conditions: the sediments were rapidly (after 6 weeks) reduced. A significant accumulation of biopolymeric carbon was observed beneath the cage both 2 weeks after the initial cage deployment, on non-impacted sediments, and 5–7 months after, and appeared to be related to the fish farm production cycle. The density of microbial communities beneath the fish farm increased only during the first month of farming activity (July) and partially 7 months after cage disposal (i.e. in January), when there was a significant sediment organic enrichment. Additional evidence of rapid impact of the fish farm on the benthic bacterial communities is provided by the increase in the numbers of autofluorescent microbial cells. The photosynthetic eukaryotic cells displayed a highly reduced contribution to total autofluorescent microbial density, indicating that their decrease is related with biopolymeric carbon accumulation, and probably was due also to “shadow effect” induced by suspended material, coming from the fish farm, on the environment below. We propose here, to apply the ratio of culturable heterotrophic bacteria to microbial direct counts (CFU/MDC) to detect fish farm impact. In cage sediments, organic enrichment and the consequent modification of the characteristics of the benthic environment, determined an increase in aerobic heterotrophic bacteria and vibrio density indicating that they are efficient colonizers of organic-rich sediments. Densities of Escherichia coli and Enterococci were not significantly higher than in the reference site, and are likely of terrestrial origin. Thus they cannot be used as specific indicators of fish farm impact.  相似文献   

Effects of progestagen exposure duration on estrus synchronization and conception rates of crossbreed ewes undergoing fixed time artificial insemination     

Wanessa Blaschi  Paula A. Lunardelli  Luciana S.R. Marinho  Marilu C. Max  Gustavo M.G. Santos  Katia C. Silva-Santos  Fabiana A. Melo-Sterza  Hernan Baldassarre  Thales R. Rigo  Marcelo M. Seneda 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):433-437

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 ± 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season.  相似文献   

SxtA and sxtG Gene Expression and Toxin Production in the Mediterranean Alexandrium minutum (Dinophyceae)     

Federico Perini  Luca Galluzzi  Carmela Dell’Aversano  Emma Dello Iacovo  Luciana Tartaglione  Fabio Ricci  Martino Forino  Patrizia Ciminiello  Antonella Penna 《Marine drugs》2014,12(10):5258-5276

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