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71.
Soybean rust in Brazil is currently controlled with several commercial fungicide premixes composed of demethylation inhibitors (EPOXiconazole, CYPRoconazole, PROThioconazole, TEBUconazole), quinone-outside inhibitors (AZOXystrobin, TriFLoXystrobin, PYRAclostrobin, PICOxystrobin), and succinate demethylation inhibitors (BENZovindiflupyr, BIXaFen, FLUXapyroxad). Here, we summarize the performance of eight premixes evaluated in 177 cooperative trials conducted in 46 locations across 10 states from 2015 to 2020. All fungicide treatments were sprayed three times starting at R1/R2. Percentage control (, %), from back-transforming meta-analytic estimates of the log of the ratio, ranged from 56.2% (PICO + CYPR) to 76.8% (BIXF + TFLX + PROT). Estimates of mean yield difference (, kg/ha) between fungicide-treated and untreated plots were greatest for BIXF + TFLX + PROT (1,080) followed by PICO + BENZ (1,010), PYRA + EPOX + FLUX (981.5), AZOX + BENZ (910), TFLX + PROT (891), PICO +TEBU (682), TFLX + CYPR (646), and PICO + CYPR (600). Significant declines in both and in as little as 4 years were detected for AZOX + BENZ (35.3%; 550 kg/ha) and PICO + BENZ (15.5%; 359.8 kg/ha). Variance in was reduced by the inclusion of baseline severity as covariate. In trials where baseline disease was ≥70%, yield was 250 kg/ha greater compared to areas with low baseline disease. Disease control and yield response were generally greater in the south-east, where the frequency of profitable scenarios was 30% higher on average than in the north-west. Results of this meta-analysis are critical for supporting decisions during planning of fungicide programmes.  相似文献   
72.
Summary Scolytidae and Platypodidae as well as other insects and mites found in imported wood. Part II The new list deals with insect and mite species collected in imported wood byWichmann () andCola last years. 40 species were found in 11 kinds of wood, most of them inPinus echinata Mill, imported from Norfolk, Virginia (U.S.A.). Nearer information onReticulitermes flavipes Koll, found byWichmann inPinus echinata in Mannheim, 1957, is given. Finally completitions are made of the list of species published in Anz. f. Schädlk. u. Pflanzenschtz. XLIV (5) p. 65–68, 1971. This list contents 41 species of insects and mites found in 9 kinds of imported wood.  相似文献   
73.
Virulence-associated gene profiling of Streptococcus suis isolates by PCR   总被引:11,自引:0,他引:11  
Definition of virulent Streptococcus suis strains is controversial. One successful approach for identification of virulent European strains is differentiation of capsular serotypes (or the corresponding cps types) and subsequent detection of virulence-associated factors, namely the extracellular factor (EF, epf), the muramidase-released protein (MRP, mrp) and the hemolysin suilysin (SLY, sly). In this work we present a novel multiplex PCR (MP-PCR) and an mrp variant PCR for identification and characterization of virulent S. suis strains. These new methods were used to identify association of disease with particular profiles of virulence-associated genes. The MP-PCR allowed identification of S. suis through detection of the housekeeping gene gdh, differentiation of four cps types (1, 2, 7 and 9), and detection of epf, mrp, sly and arcA (arginine deiminase from S. suis). Furthermore, this study describes the first PCR assay for differentiation of at least six mrp variants. Expression of the corresponding size variants of MRP was shown for four of the six mrp variants, but was undetectable for the two larger mrp variants in the particular strains investigated. The results of this study suggest that cps7 strains are associated with pneumonia and that variation of mrp is very pronounced among these strains. Gene profiles of invasive, pneumonia and carrier S. suis isolates by combination of PCR assays allowed differentiation of 24 different genotypes among cps1, 2, 7 and 9 strains. Forty-five percent of the invasive S. suis diseases investigated in this study were caused by only two of these genotypes, namely cps2/mrp+/epf+/sly+ and cps9/mrp(*)/epf-/sly+. Thus, this study demonstrates for the first time a uniform profile of the particular virulence-associated genes for the vast majority of the investigated invasive cps9 strains.  相似文献   
74.
Several studies have shown the benefit of the use of probiotics in the prevention and treatment of diseases; however, few of them have investigated the effect of probiotics on parasitosis. In this study, the effect of Saccharomyces boulardii on the intensity of infection of mice with toxocariasis was evaluated. The animals were fed with a diet supplemented with S. boulardii for 15 days before inoculation with Toxocara canis eggs and for 2 or 60 days post-inoculation. S. boulardii promoted a reduction of approximately 36% in the average number of recovered T. canis larvae, suggesting that it can be used as an alternative to help control toxocariasis.  相似文献   
75.
Stray cat colonies in urban and rural areas of Lombardy, northern Italy, were surveyed for seroprevalence of feline immunodeficiency virus (FIV) antibodies, feline leukaemia virus (FeLV) antigen and Toxoplasma gondii IgG. Of 316 cats tested, 6.6% were positive for FIV and 3.8% were positive for FeLV infection; 203 cats were tested for T gondii IgG antibodies and a prevalence of 30.5% was detected. Statistical analysis tested the influence of provenience, age, gender, health status and laboratory results on seroprevalence and found male gender and adult age were risk factors for FIV infection. FIV-infected cats were more likely to have a decreased red blood cell count than FIV seronegative cats. No predictors were significantly associated with FeLV and T gondii seropositivity. Colony cats in this study posed a limited risk for retrovirus infection to pet cats allowed outdoors, whereas toxoplasmosis exposure was comparable with the worldwide data.  相似文献   
76.
Mycobacterium bovis isolates from an outbreak of bovine tuberculosis in a herd of cattle in Rio de Janeiro, Brazil, were analysed by spoligotyping and variable-number tandem repeat PCR analysis of the mycobacterial interspersed repetitive unit and exact tandem repeats. Molecular typing revealed a high genetic diversity of strains in the herd. The genetic diversity could be explained by the introduction of infected animals from different sources.  相似文献   
77.
In late summer 2010, an outbreak of type C botulism affected the birds kept in a dam at a southern Brazilian zoo. A total of 14(10 black-necked swans, Cygnus melancoryphus; 3 Muscovy ducks, Cairina moschata; and 1 fulvous whistling-duck, Dendrocygna bicolor) out of 100 birds died after showing flaccid paralysis of the skeletal muscles characterized by general locomotion deficit, flight and swimming disorders, dropped neck, and severe dyspnea. Carcasses of dead birds (some infested by larvae of sarcophagus fly) scattered in the bird enclosure, and oxygen-free, organically rich mud and/or shallow standing waters present at the edges of the weir were identified as possible toxin sources. Postmortem examinations revealed no significant pathological changes. Epidemiologic and clinical findings indicated the diagnosis of type C botulism toxin, which was confirmed by mouse bioassay and seroneutralization.  相似文献   
78.
Neospora caninum is an intracellular parasite that causes major economic impact on cattle raising farms, and infects a wide range of warm-blooded hosts worldwide. Innate immune mechanisms that lead to protection against this parasite are still unknown. In order to investigate whether myeloid differentiation factor 88 (MyD88) is required for resistance against N. caninum, genetically deficient mice (MyD88−/−) and wild type littermates were infected with live tachyzoites and the resistance to infection was evaluated. We found that sub-lethal tachyzoite doses induced acute mortality of MyD88−/− mice, which succumbed to infection due to uncontrolled parasite replication. Higher parasitism in MyD88−/− mice was associated with the lack of IL-12 production by dendritic cells, delayed IFN-γ responses by NKT, CD4+ and CD8+ T lymphocytes, and production of high levels of IL-10. MyD88−/− mice replenished with IL-12 and IFN-γ abolished susceptibility as the animals survived throughout the experimental period. We conclude that protective IFN-γ-mediated immunity to N. caninum is dependent on initial MyD88 signaling, in a mechanism triggered by production of IL-12 by dendritic cells. Further knowledge on Toll-like receptor recognition of N. caninum antigens is encouraged, since it could generate new prophylactic and therapeutic tools to control parasite burden.  相似文献   
79.
Rhizoctonia solani AG 2-1 was recorded in Central Italy on kohlrabi plants showing root and stem rot. After artificial inoculation the fungus caused damping-off of 7-day-old seedlings and root and stem rot of 4-month-old plants developed after 15 days of incubation. This seems to be the first record ofR. solani AG 2-1 on kohlrabi.  相似文献   
80.
Objective-To determine whether partial transection of the medial branch of the suspensory ligament (MBSL) alters equine third metacarpal bone (MC3) condylar surface strains and forelimb, distal joint angles in a manner consistent with promotion of lateral condylar fracture. Study Design-In vitro biomechanical experiment. Sample Population-Right forelimbs from 7 Thoroughbred horse cadavers. Methods-Lateral and medial MC3 condylar, dorsal and abaxial, bone surface strains and distal joint angles were measured both before and after partial transection of the MBSL during in vitro axial limb compression. Dorsal, principal bone strains and abaxial, uniaxial, and proximodistal strains were compared before and after MBSL partial transection at 1,400-, 3,000-, and 5,600-N loads. Results-Bone strains increased in all locations with increasing axial load. All lateral condylar bone strains were significantly higher, and abaxial surface medial condylar bone strain was significantly lower, after partial transection of the MBSL. Respective distal joints became more flexed or extended as axial load increased but were not significantly different after partial transection of the MBSL. Conclusions-Partial transection of the MBSL increases in vitro MC3 lateral condylar bone surface strains. Clinical Relevance-Loss of integrity of the medial branch of the suspensory ligament could increase the risk for lateral condylar fracture in Thoroughbred horses by amplifying bone strain in the lateral condyle.  相似文献   
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