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111.
112.
Stefano Demichelis Claudio Arnò Domenico Bosco Daniele Marian Piero Caciagli 《Phytoparasitica》2005,33(2):196-208
The T biotype ofBemisia tabaci (Gennadius, 1889), a population found colonizingEuphorbia characias L. plants on the Nebrodi-Peloritani mountains in Sicily, was biologically characterized. The minimum development time was
29.7 days at 28°C. Based on the regression of 1/dayvs T, the rate of development was calculated as 0.00206, the theoretical lower temperature threshold for development as 9.3°C,
and the sum of effective temperatures as 485.1. At 25° C, egg-to-adult development was significantly shorter onDatura stramonium (30.1 days) than on eitherEuphorbia pulcherrima orEuphorbia characias (35.6 and 35.4 days, respectively). The fourth instar nymphs grown onD. stramonium had the typical oval outline and seven pairs of dorsal setae located on cone-like processes, often barely visible. The fourth
instar nymphs and their pupal cases grown onE. characias had the outline deformed by the presence of hairs on the lower surface of the leaf. The pupae onD. stramonium were significantly larger (both longer and wider) than those reared onE. characias; on both host plants, female pupae were significantly larger than male ones. Analysis of variance showed that width of females
onD. stramonium was significantly larger than the width of those reared onE. characias. Attempts at courtship between T- and Q-biotypes were observed, but adults from different biotypes were never seen mating.
Only males were obtained from the seven heterologous crossing attempts, either way, whereas homologous, control breeding produced
males and females. The T biotype was able to transmitTomato yellow leaf curl Sardinia begomovirus (TYLCSV) fromD. stramonium toD. stramonium, from tomato to tomato and from tomato toD. stramonium. Attempts to transmit TYLCSV fromD. stramonium to tomato were unsuccessful. The transmission efficiency was significantly lower when tomato was the test plant. The diverse
biology and ecology of the T biotype confirm that it is genetically different from most Mediterranean biotypes.
This paper is dedicated to the dear memory of our colleague Dr Claudio Arnò, who died on March 12, 2004, while this paper
was being written. 相似文献
113.
Ortega C Parilla G De Balogh K De Rosa M Gimeno O Estol L Dobosh D Leguia G Falcon N Fonseca A Torres M Caballero M Quiros J Vilhena MC Villamil LC Cediel N De Meneghi D 《Journal of veterinary medical education》2007,34(4):492-496
Continued contact between humans and animals, in combination with the ever-increasing movement of human and animal populations that is one effect of globalization, contributes to the spread of diseases, often with detrimental effects on public health. This has led professionals involved in both animal health and public health to recognize veterinary public health (VPH) as a key area for their activities to address the human-animal interface. Veterinarians, a profession with major involvement in this field, are in need of specific knowledge and skills to prevent and control public-health problems. As a result, VPH must be directly integrated into veterinary educational programs. At present, only few veterinary schools have specific VPH programs; in most institutions, VPH does not feature as a specific subject in either undergraduate or post-graduate curricula. SAPUVET and SAPUVETNET II are network projects supported by the ALFA program of the European Union (EU). Their main objectives are to reach a common understanding between European and Latin American universities in the definition of the areas in which VPH is important in their respective countries, and to design a harmonized training program for veterinarians in VPH, by making use of new technological applications and innovative teaching methodologies. The elaboration of educational material in combination with case studies presenting real-life problems provides a basis to apply the knowledge acquired on VPH. It is envisaged that the material and modules developed during the two projects will be integrated into the veterinary curricula of the participating universities, as well as in other partner organizations. 相似文献
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116.
Mario RO Barsottini Brbara A Pires Maria L Vieira Jos GC Pereira Paulo CS Costa Jaqueline Sanit Alessandro Coradini Fellipe Mello Cidnei Marschalk Eder M Silva Daniele Paschoal Antonio Figueira Fbio HS Rodrigues Artur T Cordeiro Paulo CML Miranda Paulo SL Oliveira Maurício L Sfora Marcelo F Carazzolle Silvana A Rocco Gonalo AG Pereira 《Pest management science》2019,75(5):1295-1303
117.
118.
Monica Gallo Manuela Vitulano Anna Andolfi Marina DellaGreca Esterina Conte Martina Ciaravolo Daniele Naviglio 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):141-148
Stevioside and rebaudioside A are the main diterpene glycosides present in the leaves of the Stevia rebaudiana plant, which is used in the production of foods and low-calorie beverages. The difficulties associated with their extraction and purification are currently a problem for the food processing industries. The objective of this study was to develop an effective and economically viable method to obtain a high-quality product while trying to overcome the disadvantages derived from the conventional transformation processes. For this reason, extractions were carried out using a conventional maceration (CM) and a cyclically pressurized extraction known as rapid solid-liquid dynamic extraction (RSLDE) by the Naviglio extractor (NE). After only 20 min of extraction using the NE, a quantity of rebaudioside A and stevioside equal to 1197.8 and 413.6 mg/L was obtained, respectively, while for the CM, the optimum time was 90 min. From the results, it can be stated that the extraction process by NE and its subsequent purification developed in this study is a simple, economical, environmentally friendly method for producing steviol glycosides. Therefore, this method constitutes a valid alternative to conventional extraction by reducing the extraction time and the consumption of toxic solvents and favouring the use of the extracted metabolites as food additives and/or nutraceuticals. As an added value and of local interest, the experiment was carried out on stevia leaves from the Benevento area (Italy), where a high content of rebaudioside A was observed, which exhibits a sweet taste compared to stevioside, which has a significant bitter aftertaste. 相似文献
119.
Daniele M. Nascimento Letícia R. Oliveira Luana L. Melo João C. Silva José M. Soman Karine T. Girotto Renan P. Eburneo Marcos R. Ribeiro-Junior Maria M. P. Sartori Tadeu A. F. Silva Júnior Antonio C. Maringoni 《Plant pathology》2020,69(7):1357-1367
Weeds are important alternative hosts of pathogens, responsible for the survival and spread of phytopathogenic bacteria. Our study evaluated the potential of weeds as hosts of Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff), causal agent of bacterial wilt, one of the main diseases of common beans. Cff survival was evaluated in the phyllosphere and in the rhizosphere of 21 weeds, in four experiments under field conditions, during the years 2018 and 2019. The aerial part of the plant was inoculated by spraying bacterial suspension (107 cfu/ml) of Cff, while the soil of the growing pots was infested with the same suspension. Cff survival was evaluated every 7 days, for 70 days. The identity of the bacterium was confirmed by PCR with the specific primers CffFOR2 and CffREV4, from strains recovered from all samples. Principal component analysis (PCA) showed that high temperatures and rainfall reduced Cff survival in the phyllosphere, while high temperatures reduced the survival of the bacterium in the rhizosphere. Our results demonstrated that Amaranthus viridis (family Amaranthaceae), Conyza bonariensis, Emilia fosbergii, Galinsoga parviflora, Gnaphalium purpureum (Asteraceae), Raphanus sativus, Lepidium virginicum (Brassicaceae), Commelina benghalensis (Commelinaceae), Ipomoea triloba (Convolvulaceae), Cyperus rotundus (Cyperaceae), Senna obtusifolia (Fabaceae), Digitaria insularis (Poaceae), Nicandra physalodes, and Solanum americanum (Solanaceae) are potential hosts for Cff. Their eradication in common bean fields is recommended, especially in fields with a history of bacterial wilt occurrence. 相似文献
120.
Soil organic matter formation along a chronosequence in the Morteratsch proglacial area (Upper Engadine,Switzerland) 总被引:1,自引:0,他引:1
Global warming leads to the melting of ice caps and glaciers and, consequently, the exposure of new areas of land to the atmosphere and weathering. These areas usually have a high reactivity to both biotic and abiotic changes. Proglacial areas in the Alps usually have a deglaciation time span of around 150 years (time since the end of the “Little Ice Age” in the 1850's). We investigated a chronosequence of very young soils in the proglacial area Morteratsch (Swiss Alps) to derive time-trends of soil organic matter accumulation and evolution. Total organic C and N contents, C and N contents of the various organic matter (OM) density fractions and of the labile (oxidised by H2O2) and stable (H2O2-resistant) fractions were measured. Further characterisation of OM and the various fractions was performed using Diffuse Reflection Infrared Fourier Transform (DRIFT). Soil organic matter has been accumulated over 150 years at very high rates, values lay between 7 and 36 g C/m2/year. This led to a soil organic matter abundance of about 1–5.5 kg C/m2 after 140 years. Even at the start of soil formation, a very stable fraction of soil organic matter was detectable. Stable organic matter (resistant to the H2O2 treatment) comprised about 6% of the total soil organic carbon and 10% of the total nitrogen. At the start of soil formation, a very high proportion of soil organic matter was present in the density fractions < 1.6 g/cm3. After about 140 years, 15% of soil organic carbon and 35–40% of the nitrogen was already present in the highest density fraction (> 2 g/cm3). With time, the quality of soil organic matter changed: a decrease of hydrophobicity, an increase in aromatic compounds in the bulk soil and a decrease in phenolic functional groups in the heaviest density fraction were detectable with increasing age. In general, stable organic matter as well as the density fraction > 2 g/cm3 had a low C/N ratio and were enriched in proteinaceous materials. The adsorption of proteinaceous materials points to a strong organo-mineral association. This process has existed since the very beginning of soil formation. 相似文献