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排序方式: 共有848条查询结果,搜索用时 15 毫秒
91.
Virginia Menzo Angelica Giancaspro Stefania Giove Domenica Nigro Silvana Zacheo Pasqualina Colasuonno Ilaria Marcotuli Ornella Incerti Antonio Blanco Agata Gadaleta 《Euphytica》2013,194(2):151-160
Target region amplification polymorphism (TRAP) is a relatively new PCR-based technique that detects large numbers of loci in a single reaction without extensive pre-PCR processing of samples. The aim of this study was to integrate TRAP markers in an EST-derived SSR linkage map of a RIL mapping population from the cross of the durum wheat cultivars Ciccio and Svevo, for a more general purpose of establishing a high-throughput system for genetic map saturation. Primer combinations producing PCR products with at least 4–5 polymorphic bands were selected and analyzed across the mapping population. The PCR reactions produced a total of 2,881 fragments with an average of 52 peaks per reaction. A total of 142 new TRAP markers were mapped and found to be randomly distributed in the genome. The total length of the map was 2,043.0 cM, with an average chromosome length of 145.9 cM. Homoeologous group one had the highest number of TRAP markers (38 loci) and the longest map length (407.9 cM) for a total of 87 markers, while the homoeologous group five had the lowest TRAP marker number (5 loci) and the shortest map length (232.5 cM). The distribution of markers among the seven homoeologous groups was random. The results indicate that TRAP is highly efficient in genetic mapping, generating a large number of markers scattered across the genome. This closes many existing gaps in marker coverage and may join otherwise separate linkage groups. 相似文献
92.
93.
Abstract Extract As dairy herds get larger cows have to walk further, and foot care becomes more important. Lameness from bruising of the soles of the feet is a particular hazard (Tranter and Morris 1991, especially on hard tracks with loose angular stones or grit (Clackson and Ward 1991. One way of reducing this problem might be to provide an overlay of woodchips on top of the normal hard track. This would provide a softer grit-free surface, which could be more comfortable for the cows. 相似文献
94.
Carlos Agustín Alesso María Josefina Masola María Eugenia Carrizo Pablo Ariel Cipriotti Silvia del Imhoff 《Archives of Agronomy and Soil Science》2019,65(6):822-832
The effect of tillage on soil properties varies within field due to spatial variability of soils. Mapping changes of soil penetration resistance (PR) would be useful to understand and assess tillage practices to alleviate soil compaction. The objectives were to model the short-term effect of tillage on PR and its spatial structure, and to delineate homogeneous zones based on soil response in a Typic Argiudoll previously managed under no-till. A grid sampling for PR and soil water content (SWC) were performed before and after chiselling. Spatial analysis was performed on the effect of tillage on PR data by 10 cm layers and homogeneous zones were delineated by k-means cluster analysis. The effect of tillage was ?0.33 MPa in 10–20 and 20–30 cm layer. No differences of PR were found at 0–10 cm. Short range (5–7 m) spatial structure on the horizontal plane was observed in all layers. Only 45% of the field showed a marked effect of tillage on PR. Mapping the effect of tillage on PR would be a useful approach for evaluating the global and local response of soil to tillage, as well as for delineating of areas within field for site-specific tillage practices. 相似文献
95.
Gutiérrez M Alegret S Cáceres R Casadesús J Marfà O del Valle M 《Journal of agricultural and food chemistry》2008,56(6):1810-1817
This work investigates the use of electronic tongues for monitoring nutrient solution compositions in closed soilless systems. This is a horticultural technique in which the nutrient solution is continuously recirculated and an automatic recomposition system maintains the concentration of the different ions in the optimum range for the plants. Electronic tongues used in this study comprised an array of potentiometric sensors and complex data processing by artificial neural networks. A first experiment was able to carry out the simultaneous inline monitoring of ammonium, potassium, sodium, chloride, and nitrate ions during the winter. In the second and third applications, done during summer, some changes were introduced in the sensor array to improve its response toward chloride ions and to incorporate phosphate in the model. This electronic tongue was validated with real greenhouse samples and was also able to detect the variations in the ion concentrations caused by an incorrect configuration of the recomposition system. 相似文献
96.
del Mar Caja M Blanch GP Ruiz del Castillo ML 《Journal of agricultural and food chemistry》2008,56(14):5475-5479
Pure (+)-methyl epijasmonate was isolated from lemon ( Citrus limon Burm.) for the first time. To that aim, two commercial essential oils and one homemade extract were included in the present paper. First, a study on the appropriate chromatographic conditions to avoid the epimerization from methyl epijasmonate to the more stable methyl jasmonate was accomplished. The results obtained are discussed. The presence of (+)-methyl epijasmonate in the three samples studied was initially established through the direct injection into GC-MS. However, the overlapping of (+)-methyl epijasmonate with other matrix components made it necessary to employ a multidimensional technique. RPLC-GC analysis via through-oven transfer adsorption-desorption (TOTAD) provided the selectivity and sensitivity required, reflecting that the homemade lemon extract was an adequate natural source to obtain pure (+)-methyl epijasmonate by means of the collection of the corresponding RPLC fraction. 相似文献
97.
María del Carmen Rivera-Cruz Antonio Trujillo Narcía Georgina Crdova Ballona Josef Kohler Fuensanta Caravaca Antonio Roldn 《Soil biology & biochemistry》2008,40(12):3092-3095
The aims of our study were to compare the effectiveness of poultry manure (PM) and banana waste (BW), with regard to their use as inoculant carriers of a bacterial consortium constituted by strains of Azospirillum, Azotobacter and P-solubiliser bacteria and to establish the most efficient dose of biofertilizer for a soil cultivated with banana (Musa paradisiaca AAA Simmonds), with respect to improving plant performance and soil physical and microbiological properties. Six months after planting, plant growth had increased with increase in dose of the biofertilizers applied. The biofertilizer prepared on BW enhanced the density of P-solubiliser bacteria, the concentrations of available P and foliar P to a greater extent than with the biofertilizer prepared on PM. The increases produced by the biofertilizer prepared on PM for the soil aggregate stability, enzymatic activities and the labile carbon fractions were highly correlated to the dose applied. Both biofertilizers can be considered potentially useful as inoculant carriers of PGPR but the usefulness of BW appears to be restricted to moderate doses of application (≤3%). 相似文献
98.
Diagnostic real-time PCR assay for the quantitative detection of Theileria equi from equine blood samples 总被引:1,自引:0,他引:1
Kim CM Blanco LB Alhassan A Iseki H Yokoyama N Xuan X Igarashi I 《Veterinary parasitology》2008,151(2-4):158-163
We developed a TaqMan real-time polymerase chain reaction (PCR) assay for the quantitative detection of Theileria equi from the in vitro-cultured parasite and field blood samples collected from horses living in Ghana and Brazil. The detection limit for the assay was determined to be 1.5 parasites/microl per sample, and the quantitative capacity was demonstrated using the in vitro-cultured parasite. For field applications, the real-time PCR assay was compared to a previously established nested PCR assay used as the gold standard for the real-time PCR assay. Of 65 field blood samples, 46 samples were T. equi-positive in the nested PCR assay, while the real-time PCR assay also detected the parasite in all 46 of the nested PCR-positive samples but did not detect T. equi in the remaining 19 negative blood samples. This quantitative real-time PCR assay provides a valuable tool for fast laboratory diagnostic assessment of T. equi infection in horses. 相似文献
99.
Identification of RSVP14 and RSVP20 components by two-dimensional electrophoresis and Western-blotting. 总被引:1,自引:0,他引:1
JA Cardozo M Fernández‐Juan JA Cebrián‐Pérez T Muiño‐Blanco 《Reproduction in domestic animals》2008,43(1):15-21
We have already shown that RSVP14 and RSVP20, two ram seminal plasma (SP) proteins postulated to be involved in sperm capacitation and gamete interaction can protect spermatozoa against cold-shock. In this study, we use two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) for the analysis of SP proteins of Rasa Aragonesa rams, using enhanced protein solubilization in the presence of tributyl phosphine (TBP) and a polyacrylamide linear gradient gel with a narrow pH range (4-7). The image analysis of the 2D map detected 195 protein spots, with isoelectric points (pIs) ranging from 4.5 to 6.6, and molecular weight (M(r)) from 11.7 to 90.4. Staining of 2D gels with Pro-Q Emerald 300 Glycoprotein Stain revealed that most significant proteins in ram SP are glycosylated. The removing of protein N-linked oligosaccharides improved the gel resolution. 2D-PAGE analysis of the whole fraction 6 (F6) separated from ram SP by exclusion chromatography showed six main protein spots, four (a, b, c, d) in the 14 kDa and two (e, f) in the 20 kDa region. Western-blot analyses indicated that the anti-P14 antibody recognized four spots on the SP map, 4, 5, 6 and 7, that matched with spots a, b, c, d of F6 map. The anti-P20 antibody recognized spots 13 and 14 of SP map that corresponded to spots e, f of F6 map. The deduced sequences by de novo sequencing evidenced that protein spots 7 and 13 have significant similarities to BSP family, while protein spots 4 and 14 did not appear to be homologous with any reported protein in the current mammalian Proteinbank databases. 相似文献
100.
David Ramos‐Vidales Gabriela Gmez‐Verduzco Arturo Cortes‐Cuevas Juan Carlos del Río‐García Sergio Fernndez‐Tinoco Silvestre Chrraga‐Aguilar Ernesto vila‐Gonzlez 《Journal of animal physiology and animal nutrition》2019,103(5):1484-1491
This study was performed in 360 laying Bovans White hens and aimed to evaluate the effect of Carbo‐Amino‐Phosphate‐Chelates (CAFQ) as a mineral premix and its 30% reduction by compared to inorganic trace minerals (ITM) concerning its performance, egg quality, tibia breaking strength and immunity. Sixty‐week‐old hens were assigned into three treatments with 10 replicates of 12 birds each. Treatments were as follows: (a) (100% ITM), (b) (100% CAFQ) and (c) (70% CAFQ). Based on the results obtained during 12 weeks, under the current test conditions, improved yolk colour (p < 0.05); shell breaking strength (p < 0.05); and storage time (p < 0.05) were observed in hens fed with a diet reduced by 70% in CAFQ inclusion showed similar performance behaviour and better egg breaking strength regarding with ITM, suggesting the possibility of minimizing the inclusion of trace minerals in laying hen diets improving environmental impact, in contrast to the use of inorganic sources of minerals. 相似文献