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1.
Veterinary Research Communications - The black-handed spider monkey (Ateles geoffroyi) is a platyrrhine primate distributed in southern Mexico, Central America, and part of South America. Two...  相似文献   
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The study investigated diversity and frequency of occurrence of glomale (Arbuscular- or Vesicular Arbuscular-) mycorrhizal fungi on three farming systems in a drought prone and nitrogen deficiency site in southern Malawi. The farming systems comprised of two agroforestry systems of Sesbania sesban (L) Merr intercropped with maize and Sesbania macrantha E Phillips & Hutch. intercropped with maize and a maize monocrop systems without fertilizer, with nitrogen, phosphorus and a combination of nitrogen and phosphorus. Species diversity and species frequency of occurrence were examined in soil samples obtained in the dry and wet seasons. Twelve glomale mycorrhizal species were recorded, four species being in the genus Acaulospora, four in Glomus, two in Gigaspora and two in Scutellospora. Species diversity in the two agroforestry systems were not significantly (p ≤ 0.05) different but had lower species diversity than maize monocrop with only Sesbania macrantha intercropped with maize significantly (p ≤ 0.05) lower. Species diversity was significantly increased by the inorganic nitrogen fertilizer. Inorganic phosphorus fertilizer had no effect. The study shows that the occurrence and persistence of glomale species are influenced by agroforestry combinations, and that the spores of most species are tolerant to dry conditions. Only four species responded to fertilizer application with the occurrence of spores of some species high and some low. Management practices have great implication in the persistence of spore propagules of glomale species. The order Glomale was revised in 2001 and upgraded to a phylum Glomeromycota.  相似文献   
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Near-infrared reflectance spectroscopy (NIRS) was evaluated as a possible alternative to gas chromatography (GC) for the quantitative analysis of fatty acids in forages. Herbage samples from 11 greenhouse-grown forage species (grasses, legumes, and forbs) were collected at three stages of growth. Samples were freeze-dried, ground, and analyzed by GC and NIRS techniques. Half of the 195 samples were used to develop an NIRS calibration file for each of eight fatty acids, with the remaining half used as a validation data set. Spectral data, collected over a wavelength range of 1100-2498 nm, were regressed against GC data to develop calibration equations for lauric (C12:0), myristic (C14:0), palmitic (C16:0), stearic (C18:0), palmitoleic (C16:1), oleic (C18:1), linoleic (C18:2), and alpha-linolenic (C18:3) acids. Calibration equations had high coefficients of determination for calibration (0.93-0.99) and cross-validation (0.89-0.98), and standard errors of calibration and cross-validation were < 20% of the respective means. Simple linear regressions of NIRS results against GC data for the validation data set had r2 values ranging from 0.86 to 0.97. Regression slopes for C12:0, C14:0, C16:0, C18:0, C16:1, C18:2, and C18:3 were not significantly different (P = 0.05) from 1.0. The regression slope for C18:1 was 1.1. The ratio of standard error of prediction to standard deviation was > 3.0 for all fatty acids except C12:0 (2.6) and C14:0 (2.9). Validation statistics indicate that NIRS has high prediction ability for fatty acids in forages. Calibration equations developed using data for all plant materials accurately predicted concentrations of C16:0, C18:2, and C18:3 in individual plant species. Accuracy of prediction was less, but acceptable, for fatty acids (C12:0, C14:0, C18:0, C16:1, and C18:1) that were less prevalent.  相似文献   
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Drimia maritima (squill) is a historically important medicinal plant. During the spring of 2016, small, yellow leaf spots, which became brown and finally necrotic, were observed on squill plants in Kohgiluyeh and Boyer-Ahmad Provinces in Iran. A fungus was consistently isolated from infected leaves and identified as Alternaria alternata based on morphological and phylogenetic analyses. Pathogenicity tests confirmed A. alternata to be the causal agent of the newly observed leaf spot disease. This is the first report of leaf spot on D. maritima caused by A. alternata in the world.  相似文献   
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The forage potential of chicory (Cichorium intybus L.) has not been realized in southern West Virginia (WV) because ruminants are reluctant to consume the herbage. Chicory contains bitter sesquiterpene lactones that can adversely impact palatability. This study was undertaken to determine whether sesquiterpene lactone concentrations in chicory grown in southern WV differ from those in chicory grown in central Pennsylvania (PA) where chicory is grazed readily. Herbage was collected in 1997 and 1998 from cultivars Grasslands Puna (Puna), INIA le Lacerta (Lacerta), and Forage Feast established at research sites near State College, PA, and Beckley, WV. The total concentration of sesquiterpene lactones in WV-grown cultivars was 0.58% (dry matter basis) in Puna, 0.59% in Lacerta, and 0.79% in Forage Feast in 1997 and ranged from 1.03 (Lacerta) to 1.52% (Forage Feast) in 1998. In PA-grown cultivars, sesquiterpene lactones represented 0.16 (Puna), 0.18 (Lacerta), and 0.27% (Forage Feast) of the forage dry matter in 1997 and ranged from 0.32 (Lacerta) to 0.55% (Forage Feast) in 1998. Concentrations of lactucin, lactucopicrin, and total sesquiterpene lactones in Forage Feast exceeded those in the other cultivars grown at the same site. The lowest concentrations of lactucopicrin and total sesquiterpene lactones observed among WV-grown cultivars were higher (2-fold or more) than the highest concentrations present in cultivars grown the same year in PA. Mineral analyses of soils from the two cultivation sites indicate that P availability may influence sesquiterpene lactone composition of chicory herbage. Results provide a foundation for future studies of environmental effects on sesquiterpene lactone composition and palatability of chicory herbage.  相似文献   
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In this study, we used Herbaspirillum sp. B501gfp1 (B501gfp1), an isolate from wild rice, to investigate the interaction between a non-host nitrogen-fixing endophytic bacterium and micropropagated sugarcane plants under aseptic condition. Two Japanese sugarcane plants (Saccharum sp.) cultivars (cvs) NiF8 and Ni15 were inoculated using B501gfp1 in two inoculum doses of 108 and 102 bacterial-cells-per-milliliter suspension. The results showed that bacterial cells colonized both the root and stem tissues, and colonization was apparent in the intercellular spaces. Higher bacterial numbers were detected in plant tissues inoculated with the higher inoculum concentration treatment. Bacterial numbers also varied between the two cultivars, with the higher values determined in cv Ni15. This study provides evidence that Herbaspirillum sp. B501gfp1, a rice isolate, could colonize sugarcane tissues, suggesting non-specificity of host plant among endophytes.  相似文献   
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Methylselenocysteine (MeSeCys) is an amino acid derivative that possesses potent anticancer activity in animals. Plants that can tolerate growth on soils with high Se content, known as Se hyperaccumulators, do so by converting inorganic Se to MeSeCys by the enzyme selenocysteine methyltransferase (SMT). A cDNA encoding the SMT from a Se hyperaccumulator was overexpressed in tomato (Solanum lycopersicum). Transgenic plants were provided with selenite or selenate to the roots during fruit development, and liquid chromatography-mass spectrometry was used to show that MeSeCys accumulated in the fruit but not in the leaves. Depending on the transgenic line and Se treatment, up to 16% of the total Se in the fruit was present as MeSeCys. MeSeCys was produced more effectively from selenite on a percentage conversion basis, but greater accumulation of MeSeCys could be achieved from selenate due to its better translocation from the roots. MeSeCys was heat stable and survived processing of the fruit to tomato juice.  相似文献   
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Swine are known reservoirs for Clostridioides difficile, formerly known as Clostridium difficile, and transmission from swine to human farm workers is strongly suggested by previous studies. This cross‐sectional study evaluated the potential role of farm environmental surfaces, including those in worker breakrooms and swine housing areas, in the possible transmission of C. difficile from swine to farm workers. Environmental surfaces and piglet faeces at 13 Ohio swine farms were sampled in 2015. Typical culturing techniques were performed to isolate C. difficile from samples, and amplification of toxin genes (tcdA, tcdB and cdtB) and PCR‐ribotyping were used to genetically characterize recovered isolates. In addition, sequencing of toxin regulatory gene, tcdC, was done to identify the length of identified deletions in some isolates. A survey collected farm‐level management risk factor information. Clostridioides difficile was recovered from all farms, with 42% (188/445) of samples testing positive for C. difficile. Samples collected from all on‐farm locations recovered C. difficile, including farrowing rooms (60%, 107/178), breakrooms (50%, 69/138) and nursery rooms (9%, 12/129). Three ribotypes recovered from both swine and human environments (078, 412 and 005) have been previously implicated in human disease. Samples taken from farrowing rooms and breakrooms were found to have greater odds of C. difficile recovery than those taken from nursery rooms (OR = 40.5, OR = 35.6, p < .001 respectively). Farms that weaned ≥23,500 pigs per year had lower odds of C. difficile recovery as compared to farms that weaned fewer pigs (OR = 0.4, p = .01) and weekly or more frequent cleaning of breakroom counters was associated with higher odds of C. difficile recovery (OR = 11.7, p < .001). This study provides important insights into the presence and characterization of C. difficile found in human environments on swine farms and highlights how these areas may be involved in transmission of C. difficile to swine farm workers and throughout the facility.  相似文献   
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