Effect of UV radiation on Eisenia fetida populations: The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002     

Ariadna Hamman  Fernando Roberto Momo  Andrs Duhour  Liliana Falco  Maria Cecilia Sagario  Maria Eugenia Cuadrado 《Pedobiologia》2003,47(5-6):842-845

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Phylogeny of Linearia and Notata groups of <Emphasis Type="Italic">Paspalum</Emphasis> L. (Poaceae,Panicoideae, Paniceae) and related species     

Liliana Essi  Tatiana Teixeira de Souza-Chies 《Genetic Resources and Crop Evolution》2007,54(4):779-791

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Controlled-release systems for the insect growth regulator pyriproxyfen   总被引：4，自引：0，他引：4  

Schwartz L  Wolf D  Markus A  Wybraniec S  Wiesman Z 《Journal of agricultural and food chemistry》2003,51(20):5985-5989

A simple technique was developed for the production of controlled-release systems (CRSs) for pyriproxyfen, an insect growth regulator active against the larvae of Culex pipiens, the most common species of mosquito found in developed countries. The CRSs consisted of a spongy core material encapsulated in a coating of a polyurethane or polyurea hydrogel, into which the active ingredient had been incorporated. The coating also included a surfactant to improve the low solubility in water of pyriproxyfen. The light core material enabled the CRS to float on the water surface, where the mosquitoe larvae are found. The type and amount of the polymeric coating and the amount of surfactant influenced the release profiles into water of the active ingredient. The release profiles of the CRSs were adjusted to the life cycle of the C. pipiens mosquito in order to obtain their optimal activity on the eighth day, which corresponds to the time of larval maturity.  相似文献   

Glial membranes at the node of Ranvier prevent neurite outgrowth     

Huang JK  Phillips GR  Roth AD  Pedraza L  Shan W  Belkaid W  Mi S  Fex-Svenningsen A  Florens L  Yates JR  Colman DR 《Science (New York, N.Y.)》2005,310(5755):1813-1817

Nodes of Ranvier are regularly placed, nonmyelinated axon segments along myelinated nerves. Here we show that nodal membranes isolated from the central nervous system (CNS) of mammals restricted neurite outgrowth of cultured neurons. Proteomic analysis of these membranes revealed several inhibitors of neurite outgrowth, including the oligodendrocyte myelin glycoprotein (OMgp). In rat spinal cord, OMgp was not localized to compact myelin, as previously thought, but to oligodendroglia-like cells, whose processes converge to form a ring that completely encircles the nodes. In OMgp-null mice, CNS nodes were abnormally wide and collateral sprouting was observed. Nodal ensheathment in the CNS may stabilize the node and prevent axonal sprouting.  相似文献   

Propolis extract combined with oregano essential oil applied to lima bean seeds against Sclerotinia sclerotiorum     

Cibanal  Irene Laura  Fernández  Leticia Andrea  Rodriguez  Silvana Andrea  Pellegrini  Cecilia Noemí  Gallez  Liliana María 《European journal of plant pathology / European Foundation for Plant Pathology》2022,164(1):33-43

European Journal of Plant Pathology - In this study, propolis extract (EPE) and oregano essential oil (OEO), both natural products with different bioactive compounds, were evaluated in vitro and in...  相似文献   

Composition and anti-insect activity of essential oils from Tagetes L. species (Asteraceae, Helenieae) on Ceratitis capitata Wiedemann and Triatoma infestans Klug     

López SB  López ML  Aragón LM  Tereschuk ML  Slanis AC  Feresin GE  Zygadlo JA  Tapia AA 《Journal of agricultural and food chemistry》2011,59(10):5286-5292

Essential oils from four species of the genus Tagetes L. (Asteraceae, Helenieae) collected in Tucuma?n province, Argentina, were evaluated for their chemical composition, toxicity, and olfactory activity on Mediterranean fruit fly Ceratitis capitata Wiedemann adults and for repellent properties on Triatoma infestans (Klug) (Chagas disease vector). Yields of essential oils range from 0.2 to 0.8% (v/w). The same main constituents among Tagetes minuta L., Tagestes rupestris Cabrera, and Tagetes terniflora Kunth, (cis-trans)-ocimenes, (cis-trans)-tagetones, and (cis-trans)-ocimenones showed important differences in their relative compositions. Tagetes filifolia Lag. was characterized by the recognized phenylpropanoids methylchavicol and trans-anethole as the main components. LD(50) was ≤20 μg/insect in topical bioassays. T. rupestris was the most toxic to C. capitata females, whereas the other oils presented similar toxicities against males and females. Tagetes rupestris oil attracted both sexes of C. capitata at 5 μg, whereas T. minuta showed opposite activities between males (attractant) and females (repellent). Oils from T. minuta and T. filifolia were the most repellent to T. infestans. The results suggest that compositions of essential oils influence their insecticidal and olfactory properties. The essential oils from Tagetes species show an important potential as infochemical agents on insects' behaviors. This study highlights the chemical variability of essential oils as a source of variation of anti-insect properties.  相似文献   

Comparative analyses of total phenols, antioxidant activity, and flavonol glycoside profile of cladode flours from different varieties of Opuntia spp     

Santos-Zea L  Gutierrez-Uribe JA  Serna-Saldivar SO 《Journal of agricultural and food chemistry》2011,59(13):7054-7061

The phenolic, flavonoid, and antioxidant contents of methanol extracts of nine samples of Mexican cactus ( Opuntia spp.) cladodes processed into flours were studied. Opuntia undulata contained the highest amount of phenols [905.08 ± 64.51 μg of gallic acid equivalents (GAE)/g]. The oxygen radical absorbance capacity (ORAC) of the cladode flour extracts indicated that Opuntia robusta var. Gavia [738.8 ± 89.9 μmol of Trolox equivalents (TE)/g] contained the highest antioxidant capacity. ORAC values significantly correlated to total phenols but not to flavonoid contents and were comparable to cranberries and blackberries. Glycosidic forms of isorhamnetin and kaempferol were identified via high-performance liquid chromatography-photodiode array (HPLC-PDA) and HPLC-mass spectrometry (MS), with isorhamnetin being the most abundant flavonol in all samples, except for Opuntia lindheimeri . The effectiveness of acid hydrolysis varied among species because of the different flavonol profiles. For some varieties, the triglycosidic forms were partially acid-hydrolyzed, giving an increase in the content of diglycosides. Optimization of hydrolysis for each species is required to estimate the total amount of each flavonol.  相似文献   

Application of Pilot-Scale-Constructed Wetland as Tertiary Treatment System of Wastewater for Phosphorus and Nitrogen Removal     

Ana Cristina Curia  Jair Carlos Koppe  Jo?o F. C. L. Costa  Liliana Amaral F��ris  Wagner David Gerber 《Water, air, and soil pollution》2011,218(1-4):131-143

This paper presents the results of using a pilot-scale-constructed wetland as a tertiary system to simulate the treatment conditions of wastewater effluents from the metal-mechanical industry, aiming to achieve the Brazilian legal standards of phosphorus and nitrogen emission. The macrophytes were placed in 1 m³ polyethylene tanks, daily estimating the treatment of 2 m³ of effluents. The effluents were circulated in a horizontal subsurface flow through a porous matrix of thick sand and gravel, in which the roots of the macrophytes of the species Reed (Scirpus sp.) and Cattail (Typha sp.) were fixed. Monitoring of the pilot plant was performed through a battery of physical?Cchemical and biological analyses. Despite the load variations and operational problems, the system presented a positive degree of pollutant efficiency removal, especially for phosphorus (73% medium), TKN (61% medium), and NH₄?CN (56% medium). Peak results were achieved during the last 3 months of monitoring. The chemical analysis of the support layer, plus the root system and aerial portion of the plants, revealed that these wastes could be used as fertilizer.  相似文献   

Engineering modified Bt toxins to counter insect resistance   总被引：2，自引：0，他引：2  

Soberón M  Pardo-López L  López I  Gómez I  Tabashnik BE  Bravo A 《Science (New York, N.Y.)》2007,318(5856):1640-1642

The evolution of insect resistance threatens the effectiveness of Bacillus thuringiensis (Bt) toxins that are widely used in sprays and transgenic crops. Resistance to Bt toxins in some insects is linked with mutations that disrupt a toxin-binding cadherin protein. We show that susceptibility to the Bt toxin Cry1Ab was reduced by cadherin gene silencing with RNA interference in Manduca sexta, confirming cadherin's role in Bt toxicity. Native Cry1A toxins required cadherin to form oligomers, but modified Cry1A toxins lacking one alpha-helix did not. The modified toxins killed cadherin-silenced M. sexta and Bt-resistant Pectinophora gossypiella that had cadherin deletion mutations. Our findings suggest that cadherin promotes Bt toxicity by facilitating toxin oligomerization and demonstrate that the modified Bt toxins may be useful against pests resistant to standard Bt toxins.  相似文献   

Prevalence of potato yellow vein virus (PYVV) in Solanum tuberosum Group Phureja Fields in Three States of Colombia     

Liliana Franco-Lara  Daniel Rodríguez  Mónica Guzmán-Barney 《American Journal of Potato Research》2013,90(4):324-330

Potato yellow vein virus (Crinivirus) causes leaf yellowing, is limited to the phloem and is transmitted by Trialeurodes vaporariorum and tubers. PYVV causes up to 50 % yield reduction in S. tuberosum. The prevalence of PYVV was established in Group Phureja in 2008 in the Colombian states of Cundinamarca, Antioquia and Nariño. The presence (S) or absence (NS) of symptoms was established in 24,930 plants. Symptom prevalence was as follows: Cundinamarca 0.74 %?±?0.03, Antioquia 5.4 %?±?12 and Nariño 6.2 %?±?0.11. Percentages of S plants were highly variable among different states and municipalities. PYVV was diagnosed by RT-PCR in a subsample of 1,545 plants from Cundinamarca and Nariño. RT-PCR showed that 2.4 %?±?8.3?×?10^?5 and 41 %?±?0.0009 % of the symptomless plants of Cundinamarca and Nariño respectively were positive. This suggests possible late infection of plants by the vector which did not have enough time to express symptoms, infections with two or more viruses or “virus latency”. PYVV symptomatic prevalence in Group Phureja was lower than that reported for Diacol-Capiro (Group Andigena), but increases if molecular results are taken into account. This is the first known study aimed at determining PYVV prevalence using molecular tools and extensively sampling of S.tuberosum Group Phureja plants in grower’s fields in three states and multiple municipalities of Colombia.  相似文献