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81.
A novel approach for the biological control of invasive Bagrada bugs with entomopathogenic nematodes
Lankin Gabriela Santiagos Alejandra Hermosilla Milagros Aballay Erwin San-Blas Ernesto 《Journal of pest science》2022,95(2):699-707
Journal of Pest Science - The Bagrada bug, Bagrada hilaris Burmeister (Hemiptera: Pentatomidae), an invasive pest of Palearctic origin, has become a problem in the Western Hemisphere, attacking... 相似文献
82.
Noriega-Ortega BR Armienta-Aldana E Cervantes-Pompa JÁ Armienta-Aldana E Hernández-Ruíz E Chaparro-Huerta V Bravo-Cuellar A Beas-Zárate C 《Journal of toxicologic pathology》2011,24(3):163-168
Organophosphates such as methamidophos, usually used in the agricultural field, have harmful effects on humans. Exposures to insecticides has been associated with many disorders, including damage to the central and peripheral nervous system. Chronic exposure to organophosphates may lead to persistent neurological and neurobehavioral effects. This study was conducted to determine the effect of methamidophos on [(3)H]-dopamine (DA) and gamma aminobutyric acid (GABA) release from different brain regions after chronic exposure to it for 3, 6 or 9 months. After a six-month methamidophos treatment, the mice showed high susceptibility to convulsive seizures and a reduction in stimulated gamma aminobutyric acid release from the cerebral cortex and hippocampal slices, whereas stimulated (DA) release was slightly decreased from the striatum after three months of methamidophos exposure. The results indicate changes in gamma aminobutyric acid and dopamine neurotransmission, suggesting a specific neuronal damage. 相似文献
83.
Baroni MV Podio NS Badini RG Inga M Ostera HA Cagnoni M Gallegos E Gautier E Peral-García P Hoogewerff J Wunderlin DA 《Journal of agricultural and food chemistry》2011,59(20):11117-11128
The main goal of this study was to propose a reliable method to verify the geographical origin of meat, establishing the influence of soil and water on its isotopic and elemental composition. Thus, beef meat, soil, and water samples were collected from three major cattle-producing regions of Argentina (Buenos Aires, Córdoba, and Entre Ríos). Multielemental composition was determined on these three matrices by inductively coupled plasma mass spectrometry (ICP-MS), δ(13)C and δ(15)N by isotope-ratio mass spectrometry (IRMS), and the (87)Sr/(86)Sr ratio by thermal ionization mass spectrometry (TIMS). Soil and drinking water samples could be characterized and clearly differentiated by combining the isotopic ratios and elements, demonstrating differences in geology and climatic conditions of three regions. Similarly, meat originating at each sampling area was characterized and differentiated using only five key variables (Rb, Ca/Sr, δ(13)C, δ(15)N, and (87)Sr/(86)Sr). Generalized procrustes analysis (GPA), using the three studied matrices (soil, water, and meat) shows consensus between them and clear differences between studied areas. Furthermore, canonical correlation analysis (CCA) demonstrates significant correlation between the chemical-isotopic profile of meat with those corresponding to both soil and water (r(2) = 0.93, p < 0.001; and r(2) = 0.83, p < 0.001, respectively). So far, there are clear coincidences between the meat fingerprint and those from soil/water where cattle grew, presenting a good method to establish beef provenance. To the authors' knowledge this is the first report linking the influence of soil and water all together on the composition of beef, presenting the basis for the authentication of Argentinean beef, which could be extended to meat from different provenances. 相似文献
84.
Ernesto Igartua Marian Moralejo Ana María Casas Lluís Torres José-Luis Molina-Cano 《Genetic Resources and Crop Evolution》2013,60(1):251-264
The discovery of Hordeum spontaneum C. Koch, a wild ancestor of cultivated barley, in Morocco in 1978 led to the proposal of a multicentric origin for this crop, as an alternative to the widely accepted theory of a single centre of domestication in the Fertile Crescent. Since this discovery, we have tested this hypothesis using the most advanced genetic techniques available at the time, from CM-proteins to RFLP and DNA-chloroplast markers. Nowadays, the availability of single nucleotide polymorphism (SNP) markers that are spread densely over the barley genome provides us with another powerful tool to give further support for the above. We have used 1,536 SNPs from the Barley Oligo Pool Assay 1 (BOPA1) of Illumina to characterize 107 wild and cultivated barley accessions from the Western Mediterranean, Fertile Crescent, Ethiopia, and Tibet. The results have confirmed that each location of the above-mentioned germplasm groups clusters separately. Analysis of molecular variance enabled us to focus on the chromosomal regions and loci that differentiated these groups of barley germplasm. Some of these regions contain vernalization and photoperiod response genes, some of the so-called domestication genes, as well as the most important quantitative trait locus for flowering time in the Mediterranean region. We have combined these results with other genetic evidence, and interpreted them in the framework of current theories on the onset of the Neolithic revolution in the Mediterranean region, to conclude that neither Ethiopia nor the Western Mediterranean can be ruled out as centres of barley domestication, together with the Fertile Crescent. 相似文献
85.
Angawi RF Bavestrello G Calcinai B Dien HA Donnarumma G Tufano MA Paoletti I Grimaldi E Chianese G Fattorusso E Taglialatela-Scafati O 《Marine drugs》2011,9(12):2809-2817
The chemical investigation of an Indonesian specimen of Theonella swinhoei afforded four aurantosides, one of which, aurantoside J (5), is a new compound. The structure of this metabolite, exhibiting the unprecedented N-α-glycosidic linkage between the pentose and the tetramate units, has been determined through detailed spectroscopic analysis. The four obtained aurantosides have been tested against five fungal strains (four Candida and one Fusarium) responsible of invasive infections in immuno-compromised patients. The non-cytotoxic aurantoside I (4) was the single compound to show an excellent potency against all the tested strains, thus providing valuable insights about the antifungal potential of this class of compounds and the structure-activity relationships. 相似文献
86.
Romeo J. Cabangon To Phuc Tuong Ernesto G. Castillo Lang Xing Bao Guoan Lu Guangho Wang Yuanlai Cui Bas A. M. Bouman Yuanhua Li Chongde Chen Jianzhang Wang 《Paddy and Water Environment》2004,2(4):195-206
Alternate wetting and drying irrigation (AWD) has been reported to save water compared with continuous flooding (CF) in rice cultivation. However, the reported effects on yield varied greatly and detailed agro-hydrological characterization is often lacking so that generalizations are difficult to make. Furthermore, it is not known how AWD modifies nutrient use efficiencies and if it requires different N-fertilizer management compared with CF. This study quantified the agro-hydrological conditions of the commonly practiced AWD and compared the impact of AWD and CF irrigations at different N-fertilizer management regimes on rice growth and yield, water productivity, and fertilizer-use efficiencies in five crop seasons in 1999 and 2000 at two typical lowland rice sites in China (Jinhua, Zheijang Province and Tuanlin, Hubei Province), with shallow groundwater tables.Grain yields varied from 3.2 to 4.5 t ha–1 with 0 kg N ha–1 to 5.3–8.9 t ha–1 with farmers N-rates (150 kg N ha–1 in Jinhua and 180 in Tuanlin). In both sites, no significant water by nitrogen interaction on grain yields, biomass, water productivity, nutrient uptakes and N-use efficiency were observed. Yield and biomass did not significantly differ (P >0.05) between AWD and CF and among N timings. The productivity of irrigation water in AWD was about 5–35% higher than in CF, but differences were significant (P <0.05) only when the rainfall was low and evaporation was high. Increasing the number of splits to 4–6 times increase the total N uptake, but not total P-uptake, and total K-uptake compared with farmers practices of two splits. Apparent Nitrogen recovery (ANR) increased as the number of splits increased, but there was no significant difference in ANR between AWD and CF. During the drying cycles of AWD irrigation, the perched water table depths seldom went deeper than – 20 cm and the soil in the root zone remained moist most of the time. The results suggest that in typical irrigated lowlands in China, AWD can reduce water input without affecting rice yields and does not require N-fertilizer management differently from continuous flooding. The results can be applied to many other irrigated lowland rice areas in Asia which have a shallow groundwater table. 相似文献
87.
Claudia González-Salvatierra Ernesto Iván Badano Joel Flores Juan Pablo Rodas 《林业研究》2013,24(1):23-28
Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors: white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates. 相似文献
88.
Sarah Taylor Lovell V. Ernesto Mendez Daniel L. Erickson Chloe Nathan S’ra DeSantis 《Agroforestry Systems》2010,80(2):153-171
Agroecosystems can serve as multifunctional landscapes when treed habitats such as woodlots, hedgerows, riparian buffers,
windbreaks, and orchards, are conserved on farms. We investigated the extent, pattern, and multifunctionality of on-farm treed
habitats for 16 Vermont farms in the Lamoille watershed of the Lake Champlain Basin. The site was selected because the land
use pattern is representative of the region, containing a mixture of agriculture and forest in different habitat types. We
used a GIS-based approach to delineate treed habitats on farms and conducted semi-structured interviews with farmers to explore
their perception of the functions of treed habitats. Through an evaluation of the relationship between farm characteristics
and spatial attributes of treed habitats, we found farm size to be an important variable. Larger farms had more land in treed
habitats, while the pattern of these habitats was more complex on smaller farms. Average elevation of the farm, an indicator
of biophysical conditions, was a stronger predictor of the extent of treed habitats than farm characteristics. From interviews,
we found that farmers benefited from alternative forest products, both for direct consumption and sale, including firewood,
timber, maple sugar, edible fruits and nuts, and wood crafts. Most farmers also recognized cultural and ecological functions
provided by treed habitats. These results have implications for developing policies to promote the conservation of treed habitats,
considering the preferences of the landowner or farmer. 相似文献
89.
Michael G. Ryan Jose Luiz Stape Dan Binkley Sebastiao Fonseca Rodolfo A. Loos Ernesto N. Takahashi Claudio R. Silva Sergio R. Silva Rodrigo E. Hakamada Jose Mario Ferreira Augusto M.N. Lima Jose Luiz Gava Fernando P. Leite Helder B. Andrade Jacyr M. Alves Gualter G.C. Silva 《Forest Ecology and Management》2010
Wood production varies substantially with resource availability, and the variation in wood production can result from several mechanisms: increased photosynthesis, and changes in partitioning of photosynthesis to wood production, belowground flux, foliage production or respiration. An understanding of the mechanistic basis for patterns in wood production within a stand and across landscapes requires a complete annual carbon budget. We measured annual carbon flows to wood production, foliage production and total belowground carbon flux (the sum of root production, root respiration, and mycorrhizal production and respiration) from ages three to five years in clonal Eucalyptus plantations at four sites in Brazil to test if fertility, water availability and stand structure changed wood production and by what mechanism. We also quantified the patterns in light interception and the efficiency of light use to provide additional mechanistic insights into growth responses and to determine if light-use efficiency was related to changes in flux and partitioning. 相似文献
90.
Pistocchi R Guerrini F Pezzolesi L Riccardi M Vanucci S Ciminiello P Dell'Aversano C Forino M Fattorusso E Tartaglione L Milandri A Pompei M Cangini M Pigozzi S Riccardi E 《Marine drugs》2012,10(1):140-162
The Northern Adriatic Sea is the area of the Mediterranean Sea where eutrophication and episodes related to harmful algae have occurred most frequently since the 1970s. In this area, which is highly exploited for mollusk farming, the first occurrence of human intoxication due to shellfish consumption occurred in 1989, nearly 10 years later than other countries in Europe and worldwide that had faced similar problems. Until 1997, Adriatic mollusks had been found to be contaminated mostly by diarrhetic shellfish poisoning toxins (i.e., okadaic acid and dinophysistoxins) that, along with paralytic shellfish poisoning toxins (i.e., saxitoxins), constitute the most common marine biotoxins. Only once, in 1994, a toxic outbreak was related to the occurrence of paralytic shellfish poisoning toxins in the Adriatic coastal waters. Moreover, in the past 15 years, the Adriatic Sea has been characterized by the presence of toxic or potentially toxic algae, not highly widespread outside Europe, such as species producing yessotoxins (i.e., Protoceratium reticulatum, Gonyaulax spinifera and Lingulodinium polyedrum), recurrent blooms of the potentially ichthyotoxic species Fibrocapsa japonica and, recently, by blooms of palytoxin-like producing species of the Ostreopsis genus. This review is aimed at integrating monitoring data on toxin spectra and levels in mussels farmed along the coast of the Emilia-Romagna region with laboratory studies performed on the species involved in the production of those toxins; toxicity studies on toxic or potentially toxic species that have recently appeared in this area are also reviewed. Overall, reviewed data are related to: (i) the yessotoxins producing species P. reticulatum, G. spinifera and L. polyedrum, highlighting genetic and toxic characteristics; (ii) Adriatic strains of Alexandrium minutum, Alexandrium ostenfeldii and Prorocentrum lima whose toxic profiles are compared with those of strains of different geographic origins; (iii) F. japonica and Ostreopsis cf. ovata toxicity. Moreover, new data concerning domoic acid production by a Pseudo-nitzschia multistriata strain, toxicity investigations on a Prorocentrum cf. levis, and on presumably ichthyotoxic species, Heterosigma akashiwo and Chattonella cf. subsalsa, are also reported. 相似文献