Identifying resistance gene analogs associated with resistances to different pathogens in common bean     

López CE  Acosta IF  Jara C  Pedraza F  Gaitán-Solís E  Gallego G  Beebe S  Tohme J 《Phytopathology》2003,93(1):88-95

ABSTRACT A polymerase chain reaction approach using degenerate primers that targeted the conserved domains of cloned plant disease resistance genes (R genes) was used to isolate a set of 15 resistance gene analogs (RGAs) from common bean (Phaseolus vulgaris). Eight different classes of RGAs were obtained from nucleotide binding site (NBS)-based primers and seven from not previously described Toll/Interleukin-1 receptor-like (TIR)-based primers. Putative amino acid sequences of RGAs were significantly similar to R genes and contained additional conserved motifs. The NBS-type RGAs were classified in two subgroups according to the expected final residue in the kinase-2 motif. Eleven RGAs were mapped at 19 loci on eight linkage groups of the common bean genetic map constructed at Centro Internacional de Agricultura Tropical. Genetic linkage was shown for eight RGAs with partial resistance to anthracnose, angular leaf spot (ALS) and Bean golden yellow mosaic virus (BGYMV). RGA1 and RGA2 were associated with resistance loci to anthracnose and BGYMV and were part of two clusters of R genes previously described. A new major cluster was detected by RGA7 and explained up to 63.9% of resistance to ALS and has a putative contribution to anthracnose resistance. These results show the usefulness of RGAs as candidate genes to detect and eventually isolate numerous R genes in common bean.  相似文献   

Leonotis nepetaefolia: An important plant virus reservoir in central Mexico     

Elías Piedra-Ibarra  Rodolfo De La Torre-Almaráz  Gerardo Zúñiga  Beatriz Xoconostle-Cázares  Roberto Ruíz-Medrano 《Phytoparasitica》2005,33(5):480-494

The presence of viruses in the weedLeonotis nepetaefolia in central México is reported from two field surveys.L. nepetaefolia, with viral-like symptoms such as mosaic, leaf deformation and calico, was observed growing next to cultivated fields in the Valley of Atlixco, Puebla, an important agricultural region in Mexico. The viruses harbored by this plant were characterized biologically, serologically and by molecular methods. The viruses detected wereAlfalfa mosaic virus (AMV),Cucumber mosaic virus (CMV), a satellite RNA of CMV (CMV satRNA) andTobacco mosaic virus (TMV). This last one was detected only during the first survey. CMV was the predominant virus found in both surveys, and was associated mostly to mosaic symptom. Phylogenetic analysis based on the coat protein gene sequence of CMV indicated that this isolate belongs to subgroup IA and confirmed that it is a mosaic-inducing isolate, whereas AMV belongs to subgroup II. Finally, CMV satRNA was found to be a non-necrogenic ameliorative variant, both by symptomatology and by phylogenetic analysis. Our results suggest thatL. nepetaefolia is a reservoir for several viruses in central Mexico, and given its wide distribution in several parts of the world, its role as a virus reservoir could be more general. http://www.phytoparasitica.org posting Aug. 31, 2005.  相似文献   

Prevalence of Brucella abortus antibodies in equines of a tropical region of Mexico          下载免费PDF全文

Rosa I. Acosta-Gonzlez  Ismael Gonzlez-Reyes    Gerardo H. Flores-Gutirrez 《Canadian journal of veterinary research》2006,70(4):302-304

A cross-sectional study was conducted to determinate the seroprevalence rate of equine brucellosis in the state of Tamaulipas, Mexico. Serum samples from 420 equines were analyzed with the Rose Bengal test at cell concentrations of 3% (RBT-3%) and 8% (RBT-8%), and positive results were confirmed with the Rivanol test (RT). Risk factors were determined with the prevalence ratio (PR) and the use of variables generated from a questionnaire administered to the animals' owners. Serum from 1 stallion had positive results with both the RBT-8% and the RT, for a seroprevalence rate of 0.238%. Drinking of water from a pond that was also used by cattle and dogs was the only associated risk factor for this animal (PR = 0.25). However, the results were considered false-positive, because the results for other horses in the same environmental conditions were negative. Although brucellosis is considered endemic in ruminants in the study area, the results obtained suggest that equines are not a reservoir of brucellosis and do not play an important role in the epidemiologic patterns of this disease in northeastern Mexico.  相似文献   

Evaluation of progesterone levels in feces of captive reticulated giraffe (Giraffa camelopardalis reticulata).     

Genevieve A Dumonceaux  Joan E Bauman  Gerardo R Camilo 《Journal of zoo and wildlife medicine》2006,37(3):255-261

Fresh fecal samples were collected from seven adult female reticulated giraffe (Giraffa camelopardalis reticulata). Samples were collected for several weeks before, during, and for a few weeks after gestation. Fecal samples were analyzed for progesterone levels by radioimmunoassay. There were significant differences in progesterone levels between pregestational and gestational samples and between gestational and postgestational samples. These results demonstrate that fecal progesterone levels are useful in determining pregnant versus nonpregnant reticulated giraffe.  相似文献   

Metabolizable energy,nitrogen balance,and ileal digestibility of amino acids in quality protein maize for pigs     

Gerardo Mariscal-Landin  ;Tercia Cesaria Reis de Souza  ;Ericka Ramirez Rodriguez 《畜牧与生物技术杂志(英文版)》2014,(4):461-470

Background：To compare the nutritional value and digestibility of five quality protein maize（QPM） hybrids to that of white and yellow maize,two experiments were carried out in growing pigs.In experiment 1,the energy metabolizability and the nitrogen balance of growing pigs fed one of five QPM hybrid diets were compared against those of pigs fed white or yellow maize.In experiment 2,the apparent and standardized ileal digestibility（AID and SID,respectively） of proteins and amino acids from the five QPM hybrids were compared against those obtained from pigs fed white and yellow maize.In both experiments,the comparisons were conducted using contrasts.Results：The dry matter and nitrogen intakes were higher in the pigs fed the QPM hybrids（P 〈 0.05） than in the pigs fed white or yellow maize.Energy digestibility（P 〈 0.001） and metabolizability（P 〈 0.01） were higher in the pigs fed the white and yellow maize diets than in those fed the QPM diets.The AID of lysine was higher（P〈 0.01） in the QPM diets than in the white and yellow maize.The AIDs of leucine,isoleucine,valine,phenylalanine,and methionine were lower in the QPM diets than those of maize（white and yellow）（all P 〈 0.05）.Maize（white and yellow） had greater SIDs of leucine,isoleucine,valine,phenylalanine,glutamic acid,serine,alanine,tyrosine,and proline（P 〈 0.05）.Conclusions：Based on these results,it was concluded that QPM had a lower metabolizable energy content and a higher amount of digestible lysine than normal maize.  相似文献   

Variety of non‐invasive continuous monitoring methodologies including electrical impedance tomography provides novel insights into the physiology of lung collapse and recruitment – case report of an anaesthetized horse     

Yves Moens  Johannes P Schramel  Gerardo Tusman  Tamas D Ambrisko  Josep Solà  Josef X Brunner  Lidia Kowalczyk  Stephan H Böhm 《Veterinary anaesthesia and analgesia》2014,41(2):196-204

IntroductionThe use of alveolar recruitment maneuvers during general anaesthesia of horses is a potentially useful therapeutic option for the ventilatory management. While the routine application of recruitments would benefit from the availability of dedicated large animal ventilators their impact on ventilation and perfusion in the horse is not yet well documented nor completely understood.Case historyA healthy 533 kg experimental horse underwent general anaesthesia in lateral recumbency. During intermittent positive pressure ventilation a stepwise alveolar recruitment maneuver was performed.ManagementAnaesthesia was induced with ketamine and midazolam and maintained with isoflurane in oxygen using a large animal circle system. Mechanical ventilation was applied in pressure ventilation mode and an alveolar recruitment maneuver performed employing a sequence of ascending and descending positive end expiratory pressures. Next to the standard monitoring, which included spirometry, additionally three non-invasive monitoring techniques were used: electrical impedance tomography (EIT), volumetric capnography and respiratory ultrasonic plethysmography. The functional images continuously delivered by EIT initially showed markedly reduced ventilation in the dependent lung and allowed on-line monitoring of the dynamic changes in the distribution of ventilation during the recruitment maneuver. Furthermore, continuous monitoring of compliance, dead space fraction, tidal volumes and changes in end expiratory lung volume were possible without technical difficulties.Follow upThe horse made an unremarkable recovery.ConclusionThe novel non-invasive monitoring technologies used in this study provided unprecedented insights into the physiology of lung collapse and recruitment. The synergic information of these techniques holds promise to be useful when developing and evaluating new ventilatory strategies in horses.  相似文献   

The effect of light intensity on first feeding of the spotted sand bass Paralabrax maculatofasciatus (Steindachner) larvae     

Renato Peña  Silvie Dumas  Romeo Saldivar-Lucio  Gerardo García  Ana Trasviña  & Dora Hernández-Ceballos 《Aquaculture Research》2004,35(4):345-349

The effects of light intensity on feeding incidence and prey consumption at first feeding of spotted sand bass larvae (Paralabrax maculatofasciatus Steindachner), using four light intensity treatments (0, 100, 400, and 700 lx) were evaluated. Specimens were fed the rotifer Brachionus plicatilis at a density of 3 rotifers mL^?1. One hour after the addition of prey, 30±3 (mean±SEM) larvae were sampled from each treatment aquarium. Feeding incidence was evaluated as the percentage of larvae with prey in the digestive tract. Feeding intensity was measured as the number of prey in the digestive tract of the larvae. Histological analysis was carried out to describe the eye structure at the time of first feeding. Larvae fed in darkness (0 lx) had a significantly lower (P<0.05) feeding incidence (1.2±2.2%) and intensity (0.4±0.7 rotifers larvae^?1) than those larvae fed at 100 (28±11%, 1.8±0.2 rotifers larvae^?1), 400 (48±10%, 2.4±0.3 rotifers larvae^?1), and 700 lx (52±4%, 2.4±0.1 rotifers larvae^?1). Feeding incidence of the spotted sand bass larvae increased with light intensity while the feeding intensity showed no significant difference (P>0.05) between light treatments. Histological analysis of the eye structure showed that first feeding larvae had well‐formed lens along with a retina composed of pure single cones as photoreceptors.  相似文献   

Using geomorphologic mapping to strengthen natural resource management in developing countries. The case of rural indigenous communities in Michoacan, Mexico     

Gerardo Bocco  Alejandro Velzquez  Christina Siebe 《CATENA》2005,60(3):239-253

This paper describes the use of geomorphologic knowledge for resource management in rural areas of less developed countries. Specifically, we discuss the contribution of geomorphologic mapping (coupled with landscape knowledge) to natural resource management using geographic information systems (GIS) and remote sensing techniques. We describe a case study conducted at Nuevo San Juan Parangaricutiro, an indigenous forest community in the Paricutin area, in Michoacan, Mexico.The analysis described in this paper was used to improve the mapping of forest quality units, and to explore the relationships between land suitability and land utilisation requirements for potential diversification of economic activities in the indigenous community. The approach proved useful for the management of natural resources and was made operational by the actual managers of the resources. The community of Nuevo San Juan was granted the green certification (Smart Wood) by the Forest Stewardship Council (FSC) and produced a fully automated resource management plan.  相似文献   

Wine phenolic antioxidants inhibit AP-1 transcriptional activity.   总被引：4，自引：0，他引：4  

M F Maggi-Capeyron  P Ceballos  J P Cristol  S Delbosc  C Le Doucen  M Pons  C L Léger  B Descomps 《Journal of agricultural and food chemistry》2001,49(11):5646-5652

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Polyketide Synthases in the Microbiome of the Marine Sponge Plakortis halichondrioides: A Metagenomic Update     

Gerardo Della Sala  Thomas Hochmuth  Roberta Teta  Valeria Costantino  Alfonso Mangoni 《Marine drugs》2014,12(11):5425-5440

Sponge-associated microorganisms are able to assemble the complex machinery for the production of secondary metabolites such as polyketides, the most important class of marine natural products from a drug discovery perspective. A comprehensive overview of polyketide biosynthetic genes of the sponge Plakortis halichondrioides and its symbionts was obtained in the present study by massively parallel 454 pyrosequencing of complex and heterogeneous PCR (Polymerase Chain Reaction) products amplified from the metagenomic DNA of a specimen of P. halichondrioides collected in the Caribbean Sea. This was accompanied by a survey of the bacterial diversity within the sponge. In line with previous studies, sequences belonging to supA and swfA, two widespread sponge-specific groups of polyketide synthase (PKS) genes were dominant. While they have been previously reported as belonging to Poribacteria (a novel bacterial phylum found exclusively in sponges), re-examination of current genomic sequencing data showed supA and swfA not to be present in the poribacterial genome. Several non-supA, non-swfA type-I PKS fragments were also identified. A significant portion of these fragments resembled type-I PKSs from protists, suggesting that bacteria may not be the only source of polyketides from P. halichondrioides, and that protistan PKSs should receive further investigation as a source of novel polyketides.  相似文献