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Selection of oat genotypes combining earliness and short plant height could stimulate oat cultivation worldwide. However, the mechanisms involved with the genetic control of heading date and plant height traits are not fully understood to date. This study aimed to identify genomic regions controlling heading date and plant height in two hulled by naked oat populations and to compare these genomic regions with that of other grass species. Recombinant inbred lines of each population and their parents were genotyped by a 6 K BeadChip Illumina Infinium array and assessed for heading date and plant height in two sowing dates. The quantitative trait loci (QTL) affecting these traits were detected by simple interval mapping. The two oat populations showed different genetic mechanisms controlling heading date. A major QTL was identified in one of the populations, mapped into the ‘Mrg33’ consensus linkage group from the current oat map. Two other QTL were detected into the ‘Mrg02’ and ‘Mrg24’ groups, in the second population. On the other hand, both populations presented the same genomic region controlling plant height. Six SNP markers, mapping on the same linkage group within each population, were associated with the trait, regardless the sowing date, explaining more than 20% of the phenotypic variation. Five of these six markers were mapped into three different linkage groups on the oat consensus map. Genomic regions associated with heading date and plant height in oat seem to be conserved in Oryza sativa L. and Brachypodium distachyon. Our results provide valuable information for marker-assisted selection in oats, allowing selection for earliness and plant height on early segregating generations.  相似文献   
13.
The carotenoid concentration of durum wheat is a criterion for the assessment of semolina quality, and it is of particular importance in determining the color of pasta. Thus, the development of a rapid screening method for kernel and semolina color has facilitated increasing the yellow color in durum wheat cultivars. However, the distribution of the pigment might vary within the ear of the wheat. The micromethod for the determination of yellow pigment concentration (YPC) of single wheat kernels now allows the discovery of whether this variation is the same for cultivars with different carotenoid concentrations. All of the cultivars investigated showed similar trends in the arrangements of the kernels within the ears, with the central positions of the ears being the most stable for YPC. Indeed, the best combination of higher YPC and larger kernel size is seen for the basal‐central region of the ear, which can be used for the selection during wheat‐breeding programs of cultivars with a more intense yellow color.  相似文献   
14.
The aim of this study was to evaluate the histopathological features in tissues of mice infected by human isolates (I, II, and III) or the reference M2903 strain of Leishmania braziliensis complex. BALB/c and C57Bl/6 mice were infected in the hind footpad with 106 stationary-phase promastigotes of L. braziliensis complex. The evolution of lesions was observed for 10 weeks and the animals were then euthanized and liver, spleen and popliteal lymph nodes were collected. Tissues were stained with hematoxylin and eosin and analyzed by immunohistochemistry assay. Increased thickness of infected footpads was observed in all animals, lesions were nodular and non-ulcerated. Mice infected with isolate I presented inflammatory infiltrates consisting predominantly of mononuclear cells in all tissues examined, and also a great number of megakaryocytes, compared with other isolates. Infection with isolate II led to an infected footpad enlargement not seen in other isolates. In addition, mononuclear infiltrates in the liver and hemosiderin in spleen were noted. Conversely, mice infected with either isolate III or M2903 strain only showed an increased number of megakaryocytes in spleen. All tissues examined had detectable amastigote forms of Leishmania by immunohistochemistry in all groups. Taking together, our results showed an unforeseen behavior of different isolates of L. braziliensis complex that led to diverse pathological findings.  相似文献   
15.
Interferon (IFN)-α and IFN-γ positive cells were revealed by flow cytometry in peripheral blood mononuclear cells (PBMC) of Specific Pathogen Free (SPF) pigs. A low prevalence of IFN-γ positive cells was also detected in PBMC of some Porcine Reproductive and Respiratory Syndrome virus-infected pigs and uninfected, control pigs. IFN-α positive cells showed phenotypes of both monocytes and plasmacytoid dendritic cells. The presence of IFN-α in PBMC was also confirmed by Western blotting. By immunoprecipitation, IFN-α was detected as 32 and 55-57 kDa bands in PBMC of healthy SPF piglets. These samples were also IFN-γ positive; the cytokine was revealed as 24, 37 and 54 kDa bands. The unusual molecular mass values of intracellular interferons were probably due to oligomerization, as previously described for human IFN-α. Swine intracellular IFN-α displayed the expected antiviral activity on bovine MDBK cells. The results indicate that interferons are constitutively expressed in swine leukocytes with peculiar molecular features.  相似文献   
16.
Increasing green space, especially in densely built-up areas is considered to be a valuable climate change adaptation response in order to reduce the threat of high temperatures to human health and comfort and to controlled global greenhouse gas emissions. Practical responses to climate change, under urban conditions, in order to avoid or reduce trees and shrubs vulnerability, can be considered drought resistant planting approaches, as the addition of organic amendeds to soil. The improvement of physical–chemical soil quality is a key step for carrying out xeriscaping programs of urban green spaces in Mediterranean semiarid areas. Organic amendments, particularly compost, have been receiving a renewed attention not only in horticulture but also in the context of restoring disturbed urban soils to address environmental issues as well as to improve trees and shrubs growth. The influence of increasing rates (0, 15, 30, and 45%) of composted sewage sludge (SSC) placed in the plantation hole on both urban soil properties and growth for three native Mediterranean woody hedge species was monitored over a 2-year period after planting. The experiment was supported by a xerogardening project in an urban context under semi-arid conditions. The results indicate that the urban soil physical characteristics were positively influenced by the addition of SSC: the 45% rate showed an increase in both moisture and infiltration values, thereby increasing the volume of plant-available water in the soil. The chemical properties of the amended soils were also directly affected by the SSC rate, but the effect of the compost on organic matter, nitrogen and potassium contents decreased over time. Our results prove that the hedge growth response to the compost treatments is also highly dependent on the rate of compost used. At the end of the trial, in Rhamnus and Myrthus plants 30% compost level guarantees the best performance; in fact, the further addition of 15% of compost led to a significant decrease in hedge and diameter values, in particular in Myrtle. This could be explained by the high pH at 45% compost, which would seem not to suit the physiology of the two species. On the other hand, in Phillyrea plants, the rate of 45% compost gives high performance equal to that of 30%; it would therefore seem that the high pH at 45% compost does not influence the nutritive elements’ absorption and, as a consequence, the growth. The use of composted sludge as an amendment for sclerophyllous could be feasible and, what is more, helpful to mitigate the environmental impact of organic waste disposal. Moreover more natural vegetation can be introduced into urban parks and green spaces in semi-arid environments to encourage sustainable landscaping and xerogardening.  相似文献   
17.

Background  

In domestic animals many biochemical and physiological processes exhibit daily rhythmicity. The aim of the present study was to investigate the rhythmic pattern of salivary and serum urea concentrations in sheep.  相似文献   
18.

Purpose

This study investigated the behavior of cadmium (Cd), lead (Pb), nickel (Ni), and zinc (Zn) in urban sediments collected in commercial, residential, and industrial areas of the city of Porto Alegre, Brazil, and evaluated different degrees of pollution in this urban subdrainage basin through the use of the geoaccumulation index (Igeo).

Materials and methods

Concentrations of Cd, Ni, Pb, and Zn were analyzed using acid digestion (EPA method 3050) in fractions <63 μm in 20 composite samples of urban sediment collected using a portable vacuum in 20 different sampling points on roads from three areas with diverse use: commercial, industrial, and residential.

Results and discussion

The values of Igeo were commercial area (3.35, Zn; 3.76, Cd; 3.60, Ni; 2.63, Pb) > residential area (3.34, Zn; 3.36, Cd; 2.94, Ni; 1.46, Pb) > industrial area (2.74, Zn; 1.78, Cd; 3.01, Ni; 1.45, Pb), indicating that the sediment was “highly contaminated” in the case of Zn and Ni, while for Cd, it was “moderately to highly contaminated,” and for Pb, it was “moderately contaminated.” The pollution is associated with traffic flow in all areas.

Conclusions

Research should be increased to make urban systems more sustainable, reducing their pollution potential and minimizing the delivery of potentially polluting particles into freshwater bodies. The Igeo allows for the determination of a simple index of diffuse pollution state associated with urban sediments.  相似文献   
19.
European Journal of Plant Pathology - This study aimed to evaluate the potential antagonistic role of Trichoderma in the control of Fusarium isolates belonging to the Fusarium oxysporum species...  相似文献   
20.
Although pasta is generally not considered for its aromatic properties, some evidence proves that cereal flours release volatile compounds and they might have an effect on the aroma of the transformed products. This work reports on the characterization of the volatile components of semolina and pasta obtained from four durum wheat cultivars (Triticum durum Desf., cvs. PR22D89, Creso, Cappelli, Trinakria). Semolina samples were characterized through polar metabolite profiling and fatty acid analysis to identify potential precursors of the volatile components. The results show significant differences among the samples tested with cv. Trinakria characterized by the highest content of sugars and fatty acids. Volatile composition was investigated both in semolina and in cooked pasta using headspace solid-phase micro-extraction (HS-SPME) and identified by GC–MS. Thirty-five volatile compounds including aldehydes, ketones, alcohols, terpenes, esters, hydrocarbons and a furan were identified. Significant differences were observed between semolina and pasta samples in terms of composition and amount of the volatile compounds. During cooking an increase in aldehyde content, the appearance of ketones and a decrease in alcohol content were observed. Correlations between metabolites and volatiles demonstrate that the flavour of cooked pasta may differ significantly depending on the durum wheat cultivar employed.  相似文献   
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