Natural infection of <Emphasis Type="Italic">Nicandra physaloides</Emphasis> by <Emphasis Type="Italic">Tomato severe rugose virus</Emphasis> in Brazil     

Julio C. Barbosa  Sarah S. Barreto  Alice K. Inoue-Nagata  Marcelo S. Reis  Ana Carolina Firmino  Armando Bergamin Filho  Jorge Alberto Marques Rezende 《Journal of General Plant Pathology》2009,75(6):440-443

Nicandra physaloides, a common weed in South America, was found to be infected by an isolate of Tomato severe rugose virus (ToSRV), a bipartite begomovirus. The plants developed severe yellow rugose mosaic and were collected in São Paulo State, Brazil. This isolate of ToSRV was transmitted by Bemisia tabaci B biotype from infected plants of N. physaloides to healthy plants of N. physaloides and tomato in a glasshouse. This is the first report of natural infection of N. physaloides by ToSRV in Brazil.  相似文献   

Current status of insecticide resistance in Q biotype Bemisia tabaci populations from Crete     

Emmanouil Roditakis  Maria Grispou  Evangelia Morou  Jon Bent Kristoffersen  Nikos Roditakis  Ralf Nauen  John Vontas  Anastasia Tsagkarakou 《Pest management science》2009,65(3):313-322

BACKGROUND: A major problem of crop protection in Crete, Greece, is the control of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) with chemical insecticides owing to the rapid development of resistance. The aim of this study was to investigate the establishment of resistance and the underlying mechanisms to major insecticide classes with classical bioassays and known biochemical resistance markers. RESULTS: During a 2005–2007 survey, 53 Q biotype populations were collected. Application history records showed extensive use of neonicotinoids, organophosphates, carbamates and pyrethroids. High resistance levels were identified in the majority of populations (>80%) for imidacloprid (RF: 38–1958×) and α‐cypermethrin (RF: 30–600×). Low resistance levels (RF < 12) were observed for pirimiphos‐methyl. A strong correlation between resistance to imidacloprid and the number of applications with neonicotinoids was observed. Significant correlations were observed between COE and P450‐dependent monoxygenase activity with resistance to α‐cypermethrin and imidacloprid respectively. A propoxur‐based AChE diagnostic test indicated that iAChE was widespread in most populations. Resistance levels for α‐cypermethrin were increased when compared with a previous survey (2002–2003). Differentiation of LC₅₀ values between localities was observed for imidacloprid only. CONCLUSION: Bemisia tabaci resistance evolved differently in each of the three insecticides studied. Imidacloprid resistance seems less established and less persistent than α‐cypermethrin resistance. The low resistance levels for pirimiphos‐methyl suggest absence of cross‐resistance with other organophosphates or carbamates used. Copyright © 2008 Society of Chemical Industry  相似文献   

Factorial analysis of the effect of sugarbeet vinasses on agroecological indices in horticultural field     

Miguel Angel Diez-Rojo  ;Jose Antomo Lopez-Perez  ;Maria Rosa Gonzalez-Lopez  ;Ana Piedra Buend  ;Antonio Bello  ;Gonzalo Almendros 《农业科学与技术》2009,(8):31-39

The impact on soil of applying sugarbeet vinasses （V） was analyzed through a field experiment in horticulture greenhouse, arranged in a 23 factorial design. Two levels of three independent variables--application of V, use of polyethylene cover （PC） on the soil. and soil depth （D）---on various dependent variables were studied. Vinasses favoured crop yield and reduced the number of Meloidogyne incognita juveniles in soil. The concentrations ofN. P and K increased with the interaction VxD, with PC also increasing N concentration. The amounts of humic acids and humin decreased with D; fulvic acid concentration increased with V, but decreased with the interaction VxPC. Soil physical factors were improved mainly with D and V. Aromaticity of humic acid-like fractions increased ~＇itb V. In general, V showed significant effects mainly on the topsoil, suggesting low leaching risks. The results indicate that the levels of the independent factors improving a group of variables were not the same that those contributing to another group. Therefore, their best combination should be determined for each scenario to achieve optimum agroecological performance.  相似文献   

Sequence characterized amplified region (SCAR) analysis on DNA from the three medicinal Echinacea species     

Adinolfi B  Chicca A  Martinotti E  Breschi MC  Nieri P 《Fitoterapia》2007,78(1):43-45

In our previous study, RAPD (Random Amplified Polymorphic DNA) analysis revealed species-specific markers for three medicinal Echinacea species (Asteraceae): E. angustifolia DC., E. pallida (Nutt.) Nutt. and E. purpurea (L.) Moench. In the present work, we have converted a RAPD marker (750 bp) for E. purpurea into a SCAR (Sequence Characterized Amplified Region) marker. SCAR-PCR, in fact, revealed the expected amplicon (330 bp) only in E. purpurea and not in the other two species, giving further evidence for differences in medicinal Echinacea spp. genome and confirming a greater similarity between E. pallida and angustifolia.  相似文献   

Vermicomposting as an Added-Value Post-treatment for Livestock Waste Composts     

Enrique Agulló  Mauricio Martínez-Fernández  Maria Dolores Pérez-Murcia  Aurelia Pérez-Espinosa  Raul Moral 《Communications in Soil Science and Plant Analysis》2015,46(4):208-218

The aim of this work was to study the effects of vermicomposting on selected properties of composts derived from animal and plant wastes. For this, two different worm beds were established and fed with two composts: C1, made from goat (Capra aegagrus hircus) manure and rosemary (Rosmarinus officinalis) pruning wastes, and C2, made from rabbit (Oryctolagus cuniculus) manure and grass clippings, to study the quality of the final vermicomposts. Physical and chemical properties were determined in the end products. Vermicomposting improved several properties of the composts, increasing their total water-holding capacity (in C1, from 333 to 451 mL/L, and in C2, from 371to 419 mL/L), reducing salinity (in C1, from 6.8 to 2.4 dS/m, and in C2, from 10.3 to 4.6 dS/m), and balancing pH in the final composts obtained, especially in C1 (from 8.57 to 8.02). The type of raw material used in the worm beds significantly influenced the final characteristics of the end products obtained and the development of the process, with more favorable results being obtained with the compost derived from rabbit manure and grass clippings (C2).  相似文献   

Inheritance and heritability of resistance to citrus leprosis     

Bastianel M  de Oliveira AC  Cristofani M  Filho OG  Freitas-Astúa J  Rodrigues V  Astúa-Monge G  Machado MA 《Phytopathology》2006,96(10):1092-1096

ABSTRACT The genetic inheritance of resistance to leprosis, the most important viral disease of citrus in Brazil, was characterized through the phenotypic assessment of 143 hybrids resulting from crosses between tangor 'Murcott' (Citrus sinensis x C. reticulata) and sweet orange 'Pêra' (C. sinensis), considered to be resistant and susceptible to the disease, respectively. All plants were grafted onto Rangpur lime (C. limonia) and inoculated with Citrus leprosis virus, cytoplasmic type through the infestation with viruliferous mites, Brevipalpus phoenicis. The experiments were arranged in a completely randomized block design with 10 replicates. Incidence and severity of the disease in leaves and stems as well as plant growth parameters (plant height and stem diameter) were recorded for 3 years after the infestation with the viruliferous mites. The average values of all variables were analyzed using principal component analysis, discriminant factorial analysis, estimation of the clonal repeatability coefficients, and frequency of the distributions of the average values for each measured variable. The principal component analysis resulted in the identification of at least two groups with resistance and susceptibility to leprosis, respectively. About 99% of all hybrids were correctly classified according to the discriminant factorial analysis. The broad-sense heritability coefficients for characteristics associated with incidence and severity of leprosis ranged from 0.88 to 0.96. The data suggest that the inheritance of resistance to leprosis may be controlled by only a few genes.  相似文献   

Morphological characterisation and agronomic evaluation of transgenic broccoli (Brassica oleracea L. var. italica) containing an antisense ACC oxidase gene     

Maria X. Henzi  Mary C. Christey  David L. McNeil 《Euphytica》2000,113(1):9-18

Morphological characterisation and agronomic evaluation was conducted on 12 transgenic broccolilines containing a tomato antisense1-aminocyclopropane-1-carboxylic acid (ACC) oxidase gene. Plants of three cultivars: Shogun (Sh), Green Beauty (Gy) and Dominator (D), were regenerated from hairy root cultures after co-cultivation with Agrobacterium rhizogenes strain A4T harbouring the binary vector pLN35. The T-DNA of pLN35 contains genes encoding a tomato antisense ACC oxidase gene (35S-ACC-5′7′) and a neomycin phosphotransferase II gene (NOS-NPTII-NOS) for kanamycin resistance. The transgenic plants were transferred to a greenhouse and fertile plants obtained. Integration of the foreign DNA into the broccoli genome was confirmed by the polymerase chain reaction and Southern analyses. Transgenic plants showed evidence of hairy root (HR)-induced morphological changes to varying degrees. Of the 12 characterised transgenic lines, three lines(Gy/7, D/1 and D/2) performed within the limits of acceptability for all head quality parameters analysed (size, density, colour, shape and leafiness). The ethylene production from stalks of four field-grown transgenic lines of Green Beauty broccoli showed significant reductions in activity relative to the control 98 h after harvest. The Dominator transgenic lines D/1 and D/2 showed significant improvements in head colour relative to the control from 48 h after harvest. These results are consistent with the ethylene production patterns determined previously for these lines. The head colour results are consistent with previous results suggesting that two enzyme systems may be involved in broccoli senescence, giving two bursts of ethylene production, with only the second burst inhibited by the antisense ACC oxidase gene used. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Effects of glandular trichomes on the development of Phytophthora infestans infection in potato (S. tuberosum)     

Antonia Lai  Valeria Cianciolo  Salvatore Chiavarini  Andrea Sonnino 《Euphytica》2000,114(3):165-174

S. berthaulltii Hawkes, a wild potato species, possesses two types of glandular trichomes on its leaf surface: types A and B wich confer resistance to insects. Preliminary results indicated that the presence of glandular trichomes also confers resistance to Phytophthora infestans, the causal agent of late blight. In this paper we report the evaluation of trichome characteristics (density and exudate activities) performed on 8 lines of potato, including the control varieties Desirée and Tropicana, 5 hybrid lines derived from intercrosses and backcrosses between S. tuberosum and S. berthaultii and one accession of S. berthaultii. Whole plants of the 8 genotypes were inoculated with a spore suspension of Phytophthora infestans in order to evaluate their resistance to late blight. The resultant disease incidence correlated negatively with type A trichome density and with polyphenol-oxidase (PPO) activity of type A trichome glands. The removal of type B trichomes exudate by leaf dipping in ethanol did not influence the disease development after artificial inoculation of detached leaves. Type B trichome exudate was extracted and the fraction corresponding to Fatty Acids Sucrose Esters (FASE) was recovered after Thin Layer Chromatography and tested on the fungal mycelium in vitro. The FASE exhibited a slight inhibitory effect on mycelium growth. The results of the experiments are discussed, and several hypotheses regarding the possible role of types A and B trichomes are formulated. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

The distribution and diversity of Collembola in saltmarsh habitats of the German North Sea – a preliminary study     

Maria Sterzy&#x;ska  Rainer Ehrnsberger 《Pedobiologia》2000,44(3-4)

The distribution pattern and diversity of Collembola communities in the soils of low and high intertidal saltmarshes were compared. The intertidal “mud” soils are colonized by Collembola to depth of 30 cm and at a distance of 10 m towards the sea from coastal edge. The communities of Collembola in low intertidal saltmarsh soils are dominated by a population of Archisotoma sp. The contents of organic matter in the intertidal saltmarsh soils influenced the distribution of Archisotoma sp.  相似文献   

Control of Cyclohexane Atmospheric Emissions During Soil Remediation     

Alvim Ferraz  Maria C. M.  Lourenço  João C.  Becker  Senta 《Water, air, and soil pollution》2000,120(3-4):261-272

Gaseous effluent from the treatment of contaminated soils must becontrolled to avoid atmospheric emissions of volatile organiccompounds during remediation. The combination of carbonadsorption with catalytic deep oxidation for control ofcyclohexane emissions is analysed in this paper. The activitiesof activated carbons prepared with almond shells and impregnatedwith CoO, Co₃O₄ and CrO₃ were compared, inrelation with carbon structure, catalyst content and catalystspecies. The microcatalytic-chromatographic technique developedwas very suitable for rapid comparison of the catalyticactivities. Carbons with a better development of surface areaand pore volumes showed higher catalytic activities. Theincreasing of catalyst content also increased catalyticactivity. Cobalt is better than chromium to catalyse the deepoxidation of cyclohexane, the oxidation state of cobalt inCo₃O₄ being better than in CoO.  相似文献