Genetic mapping of bph20(t) and bph21(t) loci conferring brown planthopper resistance to Nilaparvata lugens St?l in rice (Oryza sativa L.)     

L. Yang  R. B. Li  Y. R. Li  F. K. Huang  Y. Z. Chen  S. Sh. Huang  L. F. Huang  Ch. Liu  Z. F. Ma  D. H. Huang  J. J. Jiang 《Euphytica》2012,183(2):161-171

Brown planthopper(BPH) is one of the most serious and destructive insect pests of rice in most rice growing regions of the world. In this study, two major resistance genes against BPH have been identified in an Oryza rufipogon (Griff.) introgression rice line, RBPH54. Inheritance of the BPH resistance in RBPH54 was studied by screening the resistance in parents, F1, F2 and BC1 generations against BPH biotype 2. A population of BC3F2 lines was developed and SSR markers were employed for the gene mapping, and new markers were designed for fine mapping of the resistance genes, while sequence information of BAC/PAC clones was used to construct physical maps of the genes. The results showed that the BPH resistance in RBPH54 was governed by recessive alleles at two loci, tentatively designated as bph20(t) and bph21(t). The locus bph20(t) was fine mapped to the short arm of chromosome 6 about 2.7 cM to the upper marker RM435 and 2.5 cM to lower marker RM540 and in a 2.5 cM region flanked by two new SSR markers BYL7 and BYL8 which were developed in the present study. The other BPH resistance locus bph21(t) was initially mapped to a region 7.9 cM to upper marker RM222 and 4.0 cM to lower marker RM244 on the short arm of chromosome 10. For physical mapping, the bph20(t)-linked markers were landed on BAC/PAC clones of the reference cv., Nipponbare, released by the International Rice Genome Sequencing Project. The bph20(t) locus was physically defined to an interval of about 75 kb with clone P0514G1. Identification and location of these two genes in the present study have diversified the BPH resistance gene pool, which give benefit to the development of resistant rice cultivars, and the linkage PCR-based SSR markers for the bph20(t) and bph21(t) genes would help realize the application of the genes in rice breeding through marker-assisted selection.  相似文献   

Detection of bacterial wilt infection caused by Ralstonia solanacearum in potato (Solanum tuberosum L.) through multifractal analysis applied to remotely sensed data     

Perla Chávez  Christian Yarlequé  Hildo Loayza  Víctor Mares  Paola Hancco  Sylvie Priou  María del Pilar Márquez  Adolfo Posadas  Percy Zorogastúa  Jaume Flexas  Roberto Quiroz 《Precision Agriculture》2012,13(2):236-255

Potato bacterial wilt, caused by the bacterium Ralstonia solanacearum race 3 biovar 2 (R3bv2), affects potato production in several regions in the world. The disease becomes visually detectable when extensive damage to the crop has already occurred. Two greenhouse experiments were conducted to test the capability of a remote sensing diagnostic method supported by multispectral and multifractal analyses of the light reflectance signal, to detect physiological and morphological changes in plants caused by the infection. The analysis was carried out using the Wavelet Transform Modulus Maxima (WTMM) combined with the Multifractal (MF) analysis to assess the variability of high-resolution temporal and spatial signals and the conservative properties of the processes across temporal and spatial scales. The multispectral signal, enhanced by multifractal analysis, detected both symptomatic and latently infected plants, matching the results of ELISA laboratory assessment in 100 and 82%, respectively. Although the multispectral method provided no earlier detection than the visual assessment on symptomatic plants, the former was able to detect asymptomatic latent infection, showing a great potential as a monitoring tool for the control of bacterial wilt in potato crops. Applied to precision agriculture, this capability of the remote sensing diagnostic methodology would provide a more efficient control of the disease through an early and full spatial assessment of the health status of the crop and the prevention of spreading the disease.  相似文献   

Dipolar antiferromagnetism and quantum criticality in LiErF₄     

Kraemer C  Nikseresht N  Piatek JO  Tsyrulin N  Dalla Piazza B  Kiefer K  Klemke B  Rosenbaum TF  Aeppli G  Gannarelli C  Prokes K  Podlesnyak A  Strässle T  Keller L  Zaharko O  Krämer KW  Rønnow HM 《Science (New York, N.Y.)》2012,336(6087):1416-1419

Magnetism has been predicted to occur in systems in which dipolar interactions dominate exchange. We present neutron scattering, specific heat, and magnetic susceptibility data for LiErF(4), establishing it as a model dipolar-coupled antiferromagnet with planar spin-anisotropy and a quantum phase transition in applied field H(c|| = 4.0 ± 0.1 kilo-oersteds. We discovered non-mean-field critical scaling for the classical phase transition at the antiferromagnetic transition temperature that is consistent with the two-dimensional XY/h(4) universality class; in accord with this, the quantum phase transition at H(c) exhibits three-dimensional classical behavior. The effective dimensional reduction may be a consequence of the intrinsic frustrated nature of the dipolar interaction, which strengthens the role of fluctuations.  相似文献   

Direct mapping of nuclear shell effects in the heaviest elements     

E Minaya Ramirez  D Ackermann  K Blaum  M Block  C Droese  ChE Düllmann  M Dworschak  M Eibach  S Eliseev  E Haettner  F Herfurth  FP Heßberger  S Hofmann  J Ketelaer  G Marx  M Mazzocco  D Nesterenko  YN Novikov  WR Plaß  D Rodríguez  C Scheidenberger  L Schweikhard  PG Thirolf  C Weber 《Science (New York, N.Y.)》2012,337(6099):1207-1210

Quantum-mechanical shell effects are expected to strongly enhance nuclear binding on an "island of stability" of superheavy elements. The predicted center at proton number Z = 114, 120, or 126 and neutron number N = 184 has been substantiated by the recent synthesis of new elements up to Z = 118. However, the location of the center and the extension of the island of stability remain vague. High-precision mass spectrometry allows the direct measurement of nuclear binding energies and thus the determination of the strength of shell effects. Here, we present such measurements for nobelium and lawrencium isotopes, which also pin down the deformed shell gap at N = 152.  相似文献   

New World camelids and Bovine virus diarrhea virus (BVDV) infection in Switzerland     

Hilbe M  Kaufmann Ch  Zlinszky K  Zanolari P  Ehrensperger F 《Schweizer Archiv für Tierheilkunde》2012,154(4):155-158

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First evidence and molecular characterization of Babesia vogeli in naturally infected dogs and Rhipicephalus sanguineus ticks in southern France     

René M  Chêne J  Beaufils JP  Valiente Moro C  Bourdoiseau G  Mavingui P  Chabanne L 《Veterinary parasitology》2012,187(3-4):399-407

Babesiosis is an emerging tick-borne disease of animals and humans caused by intraerythrocytic protozoa of the genera Babesia and Theileria. In France canine babesiosis has a high prevalence with Babesia canis thought to be the main aetiological agent of the disease. Babesia vogeli has already been reported to occur in Europe and in other countries around the Mediterranean Sea. The tick Rhipicephalus sanguineus, the main known vector of B. vogeli, occurs in southern France. However, only one case of a B. vogeli infected dog has been reported to date in France. To gain further insight into the prevalence of Babesia and Theileria infections in dogs and ticks of the R. sanguineus complex, a study was conducted in a veterinary practice in the south of France from January to September 2010. Twelve bloods from dogs and 36 R. sanguineus ticks were analyzed using PCR and sequencing. For the analysis of ticks, a new primer was designed to specifically amplify the B. vogeli 18S rRNA gene. Four dogs (33.3%) and 8 ticks (22.2%) were found to be infected with B. vogeli. This approach has thus revealed for the first time a cluster of cases of canine babesiosis caused by B. vogeli in France and highlights the need to systematically screen for pathogens potentially responsible for canine babesiosis at the species level using suitable molecular tools.  相似文献   

Predatory aggression in a German shepherd dog     

Gonzalo A. Chávez  Álvaro J. Opazo 《Journal of Veterinary Behavior: Clinical Applications and Research》2012,7(6):386-389

This article presents a clinical case of predatory aggression that represents a problem for public health. The patient was a 2-year-old male German shepherd referred to the behavior clinic at the School of Veterinary Medicine owing to its aggressive behavior toward people and other dogs. The dog tended to form a pack with the other dogs of the household and killed neighborhood dogs, cats, hens, and rabbits. The presumptive diagnosis was “predatory aggression” associated with “territorial and protective aggression.” The risk analysis determined that the dog should be euthanized. Nevertheless, the owner refused, and hence behavior modification and drug therapy were recommended. A year later, the dog killed again (another dog), indicating that despite the drug and behavioral treatment, it is likely that its predatory aggression will never be resolved.  相似文献   

Presumed localized tetanus in two cats     

Polizopoulou ZS  Kazakos G  Georgiadis G  Soubasis N  Koutinas Ch  Koutinas AF 《Journal of Feline Medicine and Surgery》2002,4(4):209-212

In this report two cases of localised tetanus in two young (<1 year) intact male and outdoor DSH cats, which had been missing, are described. Clinical examination revealed severe muscular spasms on the right (case 1) or both thoracic limbs (case 2). In the latter cat, wrinkling of the forehead and mild trismus were also seen. The routine diagnostic workup (CBC, survey radiographs of the spine, CSF analysis) did not reveal any abnormalities in both cats. EMG testing on the affected muscles in the second animal showed persistent spontaneous motor unit potentials, strongly indicating tetanus. The treatment, that was symptomatic (diazepam, metronidazole) and supportive (physical therapy, assist feeding and intravenous fluid therapy) resulted in the progressive improvement of limb rigidity and the restoration of motor dysfunction in a period of 5- (case 1) and 2- (case 2) month duration.  相似文献   

Effect of Flavonoids and Saponins Extracted from Black Bean (Phaseolus vulgaris L.) Seed Coats as Cholesterol Micelle Disruptors     

Rocio A. Chávez-Santoscoy  Janet A. Gutiérrez-Uribe  Sergio O. Serna-Saldívar 《Plant foods for human nutrition (Dordrecht, Netherlands)》2013,68(4):416-423

Strategies for reducing plasma cholesterol have been focused on reducing the absorption or synthesis of cholesterol. The aim of this study was to correlate the content of flavonoids and saponins in black bean (Phaseolus vulgaris L.) seed coats extracts with a potential effect in lowering cholesterol absorption by the inhibition of cholesterol micellar solubility. Extracts with different flavonoids and saponins concentration were obtained from a Box-Behnken design used to optimize extraction temperature, stirring time and solvent composition. Major flavonoids and saponins were quantified by HPLC-PDA-ELSD and confirmed through mass spectrometry. Contrary to the flavonoid content, saponins were correlated to the inhibitory effect of cholesterol micelle solubility as an approach to a potential reduction of cholesterol absorption. Extracts with the highest saponin content strongly inhibited cholesterol micellization with values of 55.4?±?1.9 %, while stigmasterol used as control, only reached 12?±?2.3 % at the same concentration (5 mg/ml). The optimal extracting conditions for saponins were 25 °C, during 3 h in 85 % aqueous-methanol. Correlations of inhibitory effect of cholesterol micellar solubility with the content of each identified saponin suggested that the reduction of cholesterol micellization depends on the C-22 substitution of saponins.  相似文献   

Viruses associated with feline respiratory disease in Dunedin     

Loreen Brehaut B.Sc.  R.H. Jones B.Med.Sc. M.B. Ch.B. D.C.P.  P.J. McEwan M.Sc.  J.A.R. Miles M.A. M.D. F.R.A.C.P. P.R.S.N.Z. 《New Zealand veterinary journal》2013,61(5):82-86

Extract

In Dunedin, feline respiratory infections with a high morbidity, but a low mortality except in very young animals, commonly occur in epizootics and appear to be enzootic between these outbreaks. The affected animals develop a serous ocular discharge which later becomes mucoid, and a mucoid nasal discharge associated with sneezing especially after handling. While these signs of infection are present, the animals are anorexic and listless. The disease may last for two weeks or more and sometimes affected cats develop a chronic snuffle lasting for months despite treatment. The disease is usually referred to as “snuffles”, although it is probably identical with the syndrome called “rhinotracheitis”. In the summer time, it commonly occurs in boarding establishments where large numbers of pets collected from a wide area are left by summer vacationers. In breeding catteries, infections occur most often in the spring and especially at the time of the first warm weather. Young kittens about 5 to 10 days old are usually affected but kittens which escape infection at this stage not infrequently develop symptoms at about 6 weeks of age.  相似文献