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261.
In this study, field experiments have been conducted over three growing seasons to evaluate the effect of fungicides (triazoles and strobilurins) and a foliar fertilizer application to winter wheat at anthesis on flag leaf senescence, grain yield, bread-making quality, Fusarium head blight (FHB) disease and deoxynivalenol (DON) contamination.Flag leaf greenness was significantly influenced by the fungicide application. A delay in flag leaf senescence following triazole use did not increase grain yield. No effects of fungicide application on protein concentration were recorded. The application of strobilurin to a triazole programme did not significantly delay senescence of the flag leaf or increased yield, compared to the triazole-only application, while a consistent benefit was observed for dough strength (W). The triazole application led to significantly lower FHB symptoms and DON contamination, while the triazole-strobilurin fungicides programme led to an increase in DON contents, that were often higher than the untreated controls.Grain yield and quality were improved when a foliar feed containing macro- and micro-nutrients was added to a triazole fungicide programme, with no additional risk for DON contamination. Compared to the strobilurin fungicide application, the foliar fertilizer led to a longer delay of the flag leaf senescence and higher bread-making quality.  相似文献   
262.
Bartonella henselae has been identified and characterized for the first time in Italy. A strain, designed Pavia-1, was isolated from the blood of a cat whose owner developed cat scratch disease (CSD). Pavia-1 and two American B. henselae strains (Houston-1, ATCC 49882, type I and strain 269608, UC Davis, type II) were compared by whole-cell fatty analysis (CFA), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for protein profiles, Western immunoblotting (WB) for reactivity with polyclonal antibodies, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), type-specific 16S rRNA PCRs, and pulsed-field gel electrophoresis (PFGE). Bartonella clarridgeiae (ATCC 51734) was also included for comparison. Pavia-1 was identified as a B. henselae type I. PFGE allowed differentiation between B. clarridgeiae and B. henselae and furthermore, between all the B. henselae strains. The fingerprints of PFGE observed for Pavia-1 were distinct from those of B. henselae type II and also of Houston-1, suggesting that the two type I strains derived from two different clones. These results show the capability of B. henselae to develop genotypic variability between genetically related strains.  相似文献   
263.
A rapid detection method based on PCR amplification of Pseudomonas syringae pv. tomato chromosomal sequences was developed. Primer design was based on the P. syringae DC3000 hrpZPst gene, which maps on a pathogenicity-associated operon of the hrp/hrc pathogenicity island.A 532 bp product corresponding to an internal fragment of hrpZPst was amplified from 50 isolates of P. syringae pv. tomato belonging to a geographically representative collection. The amplification product was also obtained from three coronatine-deficient strains of P. syringae pv. tomato.On the other hand, PCR did not produce any such products from 100 pathogenic and symbiotic bacterial strains of the genera Pseudomonas, Xanthomonas, Erwinia, and Rhizobium and 75 unidentified bacterial saprophytes isolated from tomato plants. The method was tested using leaf and fruit spots from naturally-infected tomato plants and asymptomatic nursery plants and artificially contaminated tomato seeds. The results confirmed the high specificity observed using pure cultures.  相似文献   
264.
Tropical Animal Health and Production - Contagious bovine pleuropneumonia (CBPP) is a severe infectious disease caused by Mycoplasma mycoides subsp. mycoides. The peculiar pathological features of...  相似文献   
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In vitro techniques can offer a rapid, repeatable and cost‐effective alternative to in vivo experiments. We investigated the gas production (GP) of nine different feeds commonly used in Italian and Maltese pig farms in order to assess the use of the Ankom system in this species and to compare the in vitro microbial activity fresh or frozen inocula derived from piglet feces. Proximate and polyphenolic analyses were determined for all substrates. Fermentation profiles were measured according to the cumulative GP technique. Analysis of GP values revealed significant differences in the fermentation patterns mainly due to substrate and inoculum effects. Fermentation parameters varied significantly according to the substrate ingredients. The frozen inoculum generally led to more total GP than for fresh, with the exception of hard wheat bran pellets (HWBP), pelleted pulp and mature carob. Conversely the fresh fecal inoculum had an earlier maximum time to reach maximum GP than the frozen, showing a higher maximum rate of GP in all substrates excepting for HWBP. A significant difference in frozen and fresh inocula was found for the complete formulation. Further studies are required to confirm the variation between fresh and frozen fecal inocula to a wider range of feed, including those that could have negative biological effects.  相似文献   
267.
Contagious bovine pleuropneumonia (CBPP), a highly infectious and fatal disease of cattle present in many countries in sub-Saharan Africa, is usually controlled by mass vaccinations. However, vaccination against CBPP is known to cause site reactions in a percentage of cattle especially in primary vaccinations. In Zambia, a record of site reactions was kept for seven consecutive years from 2005 to 2011 to establish the level of the problem. In some areas, after 3 years of consecutive vaccination campaigns, immunization could not be implemented for a period of 2 years because of logistical difficulties or owner resistance. Whereas in the three preceding years when animals were vaccinated annually, site reactions were in the range of 6.2 %; on resumption of vaccination in the herds that had not been immunized for 2 years, site reactions averaged 21.3 %. This data shows that the T1/44 vaccine may cause severe local reactions in cattle if there is any break in annual vaccinations. It is therefore important for authorities to ensure that the cattle at risk of contracting CBPP are regularly vaccinated to avoid discouraging farmers from presenting their animals.  相似文献   
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