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191.
Reducing the level of infection of cereal heads caused by Fusarium and associated mycotoxin accumulation in grains is of a high priority in order to secure the yield, agronomic performance, and food and feed safety from field to table. Strategies to tackle the problem have been proposed at many levels, including greater knowledge of the biology of toxigenic fungi and of plant–pathogen interactions, monitoring activities which extend from the field to the end-products, pre-breeding, breeding and transgenesis to develop new resistant plant varieties, crop protection based on synthetic or natural molecules, biocontrol of fungal populations, the development and use of models that take into account the climatic conditions, and the adoption of technological protocols for reducing or inactivating mycotoxins. This review article highlights that the problem is very complex but that the scientific community continues to produce important knowledge and potential solutions. 相似文献
192.
In our ongoing search for new pharmacologically active leads from Solomon organisms, we have examined the sponge Theonella swinhoei. Herein we report the isolation and structure elucidation of swinholide A (1) and one new macrolide, swinholide J (2). Swinholide J is an unprecedented asymmetric 44-membered dilactone with an epoxide functionality in half of the molecule. The structural determination was based on extensive interpretation of high-field NMR spectra and HRESIMS data. Swinholide J displayed potent in vitro cytotoxicity against KB cells (human nasopharynx cancer) with an IC(50) value of 6 nM. 相似文献
193.
Luigi Faino Valeria Scala Alessio Albanese Vanessa Modesti Alessandro Grottoli Nicoletta Pucci Andrea Doddi Alessia L’Aurora Giuseppe Tatulli Massimo Reverberi Stefania Loreti 《Plant pathology》2021,70(8):1860-1870
Xylella fastidiosa (Xf) is a gram-negative bacterial plant pathogen that can infect over 500 plant species. While it is endemic in America, X. fastidiosa subsp. pauca was reported for the first time in Europe in 2013 on olive trees in southern Italy. The availability of fast, sensitive, and reliable diagnostic tools is indispensable for managing current and future outbreaks of Xf. In this paper, we use the OXford Nanopore Technologies (ONT) MinION platform for detecting and identifying Xf at species, subspecies, and sequence type (ST) level. Two workflows were developed: the first one provided a “shotgun” strategy, that is, exploring the possibility of detecting Xf within DNA extracted from plant samples. This allowed detection of Xf by direct DNA sequencing and identifying the subspecies only in samples with high bacterial levels. Nanopore amplicon sequencing was pursued as a second workflow. This consists of PCR amplification of a set of seven multilocus sequence typing (MLST) fragments, officially adopted for identifying Xf at type strain level, followed by Nanopore-sequencing of the amplicons and an ad hoc pipeline to generate MLST consensus calls. This combined approach, which takes only a few hours, allowed the detection and identification of Xf at ST level in plant material with low bacterial infection. 相似文献
194.
Evaluation of extracts and isolated fraction from Capparis spinosa L. buds as an antioxidant source 总被引:16,自引:0,他引:16
Germanò MP De Pasquale R D'Angelo V Catania S Silvari V Costa C 《Journal of agricultural and food chemistry》2002,50(5):1168-1171
The antioxidant activity of extracts from Capparis spinosa L. buds was evaluated using different in vitro tests: ascorbate/Fe(2+)-mediated lipid peroxidation of microsomes from rat liver; bleaching of 1,1-diphenyl-2-picryl-hydrazyl radical; and autoxidation of Fe(2+) ion in the presence of bathophenanthroline disulfonate. The methanolic extract showed strong activities in all of these in vitro tests. The amount of total phenols was determined in the methanolic extract. In addition, the level of rutin was calculated as 0.39% (w/w) by HPLC analysis. Our findings indicate the following: (a) the antioxidant efficiency of the methanolic extract may be attributed to its phenolic content; and (b) the antioxidant activity of the methanolic extract was maintained after removal of glucosinolates, confirming that these compounds do not interfere with the antioxidant properties of the extract. The results obtained from this study exalt the nutritional value of the flowering buds (capers) which are widely used as a source of flavor. 相似文献
195.
Valeria Terzi Nicola Pecchioni Primetta Faccioli Ladislav Kučera Antonio Michele Stanca 《Genetic Resources and Crop Evolution》2001,48(5):447-458
Fifteen Hordeum species and subspeciesbelonging to groups with different genomes were studied usingPCR-based markers to establish phylogenetic relationshipswithin the genus. Two hundred and seventeen RAPD and STS markers wereused to calculate genetic distances and construct phylogenetic trees.The phenetic analysis clearly separated the primary gene pool,represented by H. vulgaressp. vulgare, H.vulgare ssp. vulgare convar. vulgare f. agriochriton andH. vulgare ssp.spontaneum, from the secondary gene pool,represented by H. bulbosumand the tertiary gene pool, represented by American wild barleys andH. bogdanii. Data obtainedfrom PCO analysis are in complete agreement with taxonomicclassifications proposed previously, which were comparisons ofnumerous morphological, cytological and reproductivecharacters. 相似文献
196.
Valeria Terzi Caterina Morcia A. Michele Stanca Ladislav Kucera Clara Fares Pasquale Codianni Natale Di Fonzo Primetta Faccioli 《Genetic Resources and Crop Evolution》2007,54(7):1613-1621
In the last few years, the renewed interest for emmer wheat (Triticum dicoccon Schrank) in Italy has stimulated breeding programs for this crop releasing improved genotypes obtained not only by selection
from landraces, but even by crosses with durum wheat (Triticum durum Desf.) varieties. The purpose of this work has been to uncover the genetic make-up of some emmer × durum derivatives, specifically
by comparing the differences from their parents. Genetic diversity of advanced breeding lines and varieties derived from a
durum × emmer cross has been evaluated on the basis of AFLP and SSR markers in comparison with the corresponding emmer and
durum wheat parent for addressing the seminal question of how much ‘wild’ variation remains after selection for agronomic
type. 相似文献
197.
Strohmeyer RA Morley PS Hyatt DR Dargatz DA Scorza AV Lappin MR 《Journal of the American Veterinary Medical Association》2006,228(4):537-542
OBJECTIVE: To evaluate bacterial and protozoal contamination of commercially available raw meat diets for dogs. DESIGN: Prospective longitudinal study. SAMPLE POPULATION: 240 samples from 20 raw meat diets for dogs (containing beef, lamb, chicken, or turkey), 24 samples from 2 dry dog foods, and 24 samples from 2 canned dog foods. PROCEDURE: Each product was purchased commercially on 4 dates approximately 2 months apart. Three samples from each product at each sampling period were evaluated via bacterial culture for non-type-specific Escherichia coli (NTSEC), Salmonella enterica, and Campylobacter spp. Antimicrobial susceptibility testing was performed on selected isolates. Polymerase chain reaction assays were used to detect DNA from Cryptosporidium spp, Neospora spp, and Toxoplasma spp in samples obtained in the third and fourth sampling periods. RESULTS: One hundred fifty-three of 288 (53%) samples were contaminated with NTSEC. Both raw and prepared foods contained NTSEC during at least 1 culture period. Salmonella enterica was recovered from 17 (5.9%) samples, all of which were raw meat products. Campylobacter spp was not isolated from any samples. In 91 of 288 (31.6%) samples, there was no gram-negative bacterial growth before enrichment and in 48 of 288 (16.7%) samples, there was no aerobic bacterial growth before enrichment. Susceptibility phenotypes were variable. Cryptosporidium spp DNA was detected in 3 samples. CONCLUSIONS AND CLINICAL RELEVANCE: Bacterial contamination is common in commercially available raw meat diets, suggesting that there is a risk of foodborne illness in dogs fed these diets as well possible risk for humans associated with the dogs or their environments. 相似文献
198.
Pesente P Rebonato V Sandri G Giovanardi D Ruffoni LS Torriani S 《Veterinary microbiology》2006,114(3-4):214-224
We investigated the dynamics of porcine reproductive and respiratory syndrome virus (PRRSV) variability in a range of swine PRRS-positive farms located in Northern Italy, to provide insights into the epidemiology and diffusion of the virus, particularly throughout the entire swine production chain. In this context, we also examined the effectiveness and the critical points of a recently developed gilts acclimatization program in swine breeder farms. To achieve these aims, we designed new primers and determined 64 complete open reading frame 5 (ORF5) sequences, representing Italian PRRSV field strains and the European vaccine Porcilis strain (Intervet); in addition, the more conserved ORF7 of 11 PRRSV strains were sequenced. The domains' prediction of their putative protein sequences was performed as well. Based on these sequences, phylogenetic trees were inferred which revealed a high degree of variability among the PRRSV Italian strains. The outcomes of the phylogenetic analysis showed that the most frequent source of infection in PRRS-positive farms (sow herds, nursery sites, fattening units) was the introduction of animals carrying a new variant and not the modification of already present variants; moreover, the integration of data from phylogenetic analysis and from the clinical and serological status of the swine herds suggested that the acclimatization program could be a valid tool to stabilize the PRRS clinical picture in farms, only when applied in combination with rigorous bio-security routine management and avoid the incoming of new PRRSV variants. 相似文献
199.
Chiara Broccanello J. Mitchell McGrath Lee Panella Kelley Richardson Andrew Funk Claudia Chiodi Filippo Biscarini Valeria Barone Andrea Baglieri Andrea Squartini Giuseppe Concheri Piergiorgio Stevanato 《Euphytica》2018,214(1):14
Rhizomania is one of the most devastating biotic stresses affecting sugar beet (Beta vulgaris L.). It is caused by Beet necrotic yellow vein virus (BNYVV) vectored by the plasmodiophorid Polymyxa betae K. The only means available to control the disease is the use of genetically resistant varieties. “Rizor” or “Holly” (Rz1) and WB42 (Rz2) have been the most widely used resistance sources in the commercial varieties. Recently, naturally occurring resistance-breaking (RB) rhizomania strains have been identified causing major concerns. The aim of this study was to identify SNP mutations that show associations with resistance to rhizomania in sugar beet plants grown under resistance-breaking (RB)-BNYVV soils. Rhizomania virus content was evaluated by indirect triple-antibody sandwich-ELISA within two F 2 segregating populations respectively grown on an AYPR and IV-BNYVV strain infected soils. Bulked segregant analysis (BSA) was performed. The resistant and susceptible plants were genotyped with a 384-SNPs panel. Of the 384 SNPs, SNP249 was found to associate with the resistance both to the AYPR strain (R 2 = 0.37; P = 0.0004) and to the IV-BNYVV (R 2 = 0.09; P = 0.0074). Our results suggested that the SNP249 could be readily applicable for marker-assisted breeding of resistance to AYPR strain of rhizomania. 相似文献
200.
Valeria Altieri Silvio De Franco Fabio Lombardi Pasquale Antonio Marziliano Giuliano Menguzzato Paolo Porto 《Journal of Soils and Sediments》2018,18(12):3378-3387