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71.
Delphine Sciama Laurent Augusto Jean-Luc Dupouey Maya Gonzalez Concepción Moares Domínguez 《Forest Ecology and Management》2009
The aim of this work was to investigate differences in soil chemistry and understory composition between recent forests (sites afforested in the last 170 years) and ancient forests growing on non-acidic soils. The study was carried out on hardwood forests at moderate elevation (400–600 m asl) in the Jura Mountains (N.E. France) on four main pedological substrates with different characteristics. The floristic composition of 127 stands from recent forests (n = 65) or ancient forests (n = 62) was surveyed. Some functional traits and the Ellenberg indicator values of the surveyed species were recorded. In addition, the topsoil from 30 stands was analysed. The composition of the flora was analysed by Detrended Correspondence Analysis and the species which were typical of one class of forest age were identified using a chi-square (χ2) test. The difference between forest classes for plant traits, their indicator values, or soil chemistry was tested using the generalized linear model and Bonferroni t-tests (or Kruskall–Wallis tests). The floristic composition of the ancient forests was significantly different from that of the recent forests and was characterized by a high occurrence of shrub species in recent forests. These differences were associated with higher specific leaf area, low-range seeds dispersal, and some life forms like geophytes. There was no clear difference in soil chemistry between the two classes of forests, except for δ15N values. The weakness of the difference in the soil between ancient and recent forests suggested that changes in soil chemistry caused by a former agricultural land use were not responsible for the differences in understory composition recorded. The differences in functional traits between the two forest classes supported this conclusion. We finally concluded that (i) past land use modifies the vegetation composition of current forests, even on neutral soils and that (ii) in our context, biological filters were probably responsible for these changes. 相似文献
72.
F. Abderrahim E. Huanatico R. Repo-Carrasco-Valencia S.M. Arribas M.C. Gonzalez L. Condezo-Hoyos 《Journal of Cereal Science》2012
Germination of cereals/pseudo-cereals has been suggested as an effective method to increase antioxidant compounds. However, this process could also lead to high reducing sugar levels and subsequent Maillard reaction products. The aim of this work was to determine the time course effect of canihua (Chenopodium pallidicaule) germination on: 1) antioxidant capacity, 2) extractable and non-extractable phenolic compounds content, 3) Maillard reaction products and 4) oxidative stress markers. Germination increased antioxidant capacity, phenolic compounds and Maillard reaction products, including advanced glycated end products while it decreased oxidative stress markers. All parameters exhibited a similar time course pattern with a maximum at 72 h. In addition to the increase in phenolic compounds and antioxidant capacity, canihua germination produced advanced glycated end products. The impact on human health of these compounds in germinated seeds deserves future attention. 相似文献
73.
RNAseq analysis reveals the role of secondary metabolism in the response of URS 21, a race‐nonspecific resistant cultivar,to crown rust
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74.
This report describes a suspect case of West Nile virus (WNV) encephalomyelitis, reported for the first time in a horse in the UK. The affected gelding had been imported from the Republic of Cyprus and travelled through several WNV endemic areas in Europe before arriving at the premises in Lincolnshire. Clinical signs included muscle fasciculations, weakness of the hindlimbs and transient lip twitching that quickly progressed to depression and recumbency. West Nile virus specific antibodies were detected by serological tests in the absence of a previous history of vaccination. The horse improved clinically 10 days after the onset of disease and fully recovered in 12 weeks. Follow‐ups at 12 and 20 months post event did not reveal any sequela and the horse was performing adequately at novice level. This article refers to the same horse mentioned by Fooks et al. (2014) and it is an extension of the previous published work. 相似文献
75.
SM Gonzalez CB da Silva AG Lindquist I Bufalo F Morotti LA Lisboa M Seneda 《Reproduction in domestic animals》2017,52(5):836-841
The goal of this study was to determine the distribution of pre‐antral follicles in the ovarian parenchyma of mares. For Experiment 1, each ovary was cut longitudinally at the greater curvature, performing two hemiovaries. After that, six fragments from each hemiovary were obtained, resulting in 12 fragments, which were divided into the innermost region of the parenchyma, the middle region and the outermost region. All the three obtained sections were cut transversally to obtain two fragments from each one. For Experiment 2, each ovary also submitted to a longitudinal cut on the greater curvature, forming two hemiovaries. Each hemiovary was sectioned into four symmetrical fragments, resulting in eight fragments per ovary. The fragments were related as being near to or far from the ovulatory fossa. The fragments of both experiments were immediately fixed in Carnoy for 12 hr and kept in 70% ethanol for 24 hr. Follicles were classified according to the stages of development and for morphological integrity according to oocyte morphology and granulosa cells. After the histological assessment, a total of 1,130 follicles were visualized from Experiment 1, being 1,054 (93.3%) primordial follicles and 76 (4.7%) follicles in development. The innermost region had the highest percentage of pre‐antral follicles compared to the other regions (p < .05). The middle and outermost regions showed higher percentages of intact primordial and developing follicles than the innermost region (p < .05). Considering Experiment 2, 938 follicles were found, being 894 (95.3%) primordial and 44 (4.7%) follicles in development. The region near the ovulatory fossa presented higher (58.7%; 551 of 938) follicular concentration compared to the region far from the ovulatory fossa (41.3%; 387 of 938; p < .05). As a conclusion, distribution of pre‐antral follicles in the equine ovary has a specific pattern through the parenchyma. Also, the follicular integrity differed in the studied ovarian areas. 相似文献
76.
Shikha Singh Nathan Brandenburg Laurent Ahiablame Arturo Gonzalez Jeppe Kjaersgaard Todd P. Trooien Sandeep Kumar 《Water, air, and soil pollution》2017,228(10):389
Manure application on frozen soil, which is a common practice in the upper Midwest of USA, results in degraded soil and water quality. During snowmelt or precipitation events, water runoff carries nutrients into nearby streams and impairs the water quality. There is a need, therefore, to identify improved management of manure application in the soils. This study was conducted to assess water quality impacts associated following manure application during winter months when soil is completely covered with snow. The study site included three watersheds, named south (SW), east (CW), and north (NW) managed with a corn (Zea mays L.)-soybean (Glycine max L.) rotation located in South Dakota. The SW and NW were used as treatment, and CW as the control watershed. The treatments included manure application on the upper half of the SW and lower half of the NW, and CW received no manure application. This study showed that manure improved soil properties including infiltration rate and organic matter. Nitrogen and phosphorus losses in the surface runoff were higher from NW compared to that of SW. The CW had similar nutrient losses compared to the NW with slight differences. It can be concluded that maintaining a setback distance can help in improving the environmental quality as well as managing the agricultural wastes during the winter months. 相似文献
77.
78.
R. Narancio P. Zorrilla C. Robello M. Gonzalez F. Vilaró C. Pritsch M. Dalla Rizza 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(4):823-835
Solanum commersonii is a wild species related to the cultivated potato. Some S. commersonii genotypes have been proven to be resistant to the pathogenic bacteria Ralstonia solanacearum, which causes damage in potato and other economically important crops. Here an expression analysis of the response of a resistant S. commersonii genotype against R. solanacearum was performed using microarrays. The aims of this work were to elucidate the molecular processes involved in the interaction, establish the timing of the response, and contribute to identify genes related to the resistance. The response to the treatment was already initiated at 6 h post-inoculation (hpi) and was established at 24 hpi; during this period, a high number of genes was differentially expressed and several candidate genes for the resistance of S. commersonii to R. solanacearum were identified. At an early stage, the photosynthetic process was highly repressed and several genes encoding proteins related to reactive oxygen species (ROS) production were differentially expressed. The induction of ERF and ACC-oxidase genes related to the ethylene pathway and PR1 related to the salicylic acid pathway suggested the induction of both pathways, and back up the previously reported hemibiotrophic nature of the pathogen. Five genes related to plant defence and observed to be differentially expressed at the first two time points were validated by real time PCR. This work gives a glimpse to the molecular processes involved in S. commersonii resistance and identifies the species as a valuable genetic source for potato breeding against bacterial wilt. 相似文献
79.
VP Dia T Gomez G Vernaza M Berhow YK Chang EG de Mejia 《Journal of agricultural and food chemistry》2012,60(32):7886-7894
Soybean contains constituents that have antinutritional and bioactive properties. Enzymatic hydrolysis and germination can enhance the biological activity of these compounds in soybean. The objective of this study was to investigate the effect of germination, Alcalase (protease) hydrolysis, and their combination on the concentrations of antinutritional and bioactive compounds in Brazilian soybean cultivar BRS 133. A combination of germination and Alcalase hydrolysis resulted in the degradation of Bowman-Birk inhibitor (BBI), Kunitz trypsin inhibitor (KTI), and lunasin by 96.9, 97.8, and 38.4%. Lectin was not affected by any of the processing treatments when compared to nongerminated and nonhydrolyzed soy protein extract. Total isoflavones (ISF) and total saponins (SAP) increased by 16.2 and 28.7%, respectively, after 18 h of germination, while Alcalase hydrolysis led to the reduction of these compounds. A significant correlation was found between concentrations of BBI and KTI, BBI and lunasin, BBI and ISF, KTI and lunasin, KTI and ISF, KTI and SAP, lunasin and ISF, and ISF and SAP. Germination and Alcalase hydrolysis interacted in reducing BBI, ISF, and SAP. This study presents a process of preparing soy flour ingredients with lower concentrations of antinutritional factors and with biologically active constituents, important for the promotion of health associated with soybean consumption. In conclusion, 18 h of germination and 3 h of Alcalase hydrolysis is recommended for elimination of protease inhibitors, while bioactives are maintained by at least 50% of their original concentrations. 相似文献
80.
Ricardo Bressani Jorge Mario Gonzalez Luiz G. Elias Mario Melgar 《Plant foods for human nutrition (Dordrecht, Netherlands)》1987,37(1):59-67
Four selections of three amaranth species were used in the study:A. cruentus (US Rodale 82S-1034),A. hypochondriacus (US Rodale 81S-1024).A. caudatus (Cusco, Peru CAC-2002) andA. cruentus (GUA-17). These were fertilized with levels of 0, 30, 60 and 90 kg/ha of a 12-24-12 fertilizer formulation applied to experimental plots 3×4m2 in four replications. The harvested grain was used for protein and fat analysis, and for protein quality evaluations on raw and on heat processed samples.A. cruentus (US) andA. hypochondriacus flowered at 43–44 days at 60 and 43cm, respectively,A. caudatus (Peru) at 51 days and 65cm, andA. cruentus (Gua) at 50 days and 80cm height. Days at harvest varied from 100 to 129 days at heights of 125 to 180cm. Yield of grain fromA. hypochondriacus (US) andA. cruentus (Gua) was higher than forA. cruentus (US) andA. caudatus, but did not differ for each pair. although not influencing yield, the application of fertilizer increased protein content forA. caudatus (Peru) from 12.35 to 14.50%; but not the protein content of the other selections. The fat content was affected differently in all four selections. The application of fertilizer did not affect protein quality either in raw or processed grain. On the other hand, processing increased protein quality, food intake, and animal performance significantly most clearly seen withA. cruentus (US) andA. caudatus (Peru) and to a lesser extent forA. hypochondriacus (US) andA. cruentus (Gua)). The data obtained showed inconsistent effects on yield and chemical composition, and no effect on protein quality with fertilizer application. 相似文献