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1.
2.
Mercè Llugany Roser Tolrà Sandra Raquel Martín Charlotte Poschenrieder Juan Barceló 《植物养料与土壤学杂志》2013,176(6):851-858
Glutathione (GSH) and phenolics play an important role in plant defense against metal‐ion toxicity. The antioxidant activity and metal‐binding capacity of these compounds can account for the protective effects. In contrast to animal‐cell models, however, the possible interplay among these substances in stress defense of plants is poorly investigated. This study compares the influence of cadmium (Cd) on the profiles of both soluble phenolics and GSH in shoots of different Thlaspi and Noccaea species: two ecotypes of the nonhyperaccumulator T. arvense differing in Cd resistance (ecotype Aigues Vives, Cd‐sensitive, and ecotype Jena, Cd‐resistant) and two Cd‐tolerant Cd‐Zn hyperaccumulators N. praecox and N. caerulescens (formerly Thlaspi praecox and T. caerulescens). To reveal the possible influence of Cd‐induced sulfur (S) shortage on the stress response, plants receiving normal S concentrations (500 μM MgSO4) and plants treated with surplus S (500 μM MgSO4 + 500 μM K2SO4) were analyzed. Our working hypothesis was that species differences in tolerance to high tissue Cd concentrations should be reflected by differences in endogenous levels of GSH and phenolic compounds. The results reveal clear species‐dependent differences in both the constitutive patterns and the Cd‐ and S‐induced changes in shoot concentrations of GSH and phenolics. However, no simple relationship between these shoot concentrations and Cd accumulation and tolerance can be established. 相似文献
3.
Fernando González-Andrés Pedro A. Casquero Cristina San-Pedro Elías Hernández-Sánchez 《Genetic Resources and Crop Evolution》2007,54(1):27-44
All the accessions (35) of white lupin (Lupinus albus L.) landraces collected from northwest Iberian plateau and maintained at the Spanish germplasm collection (CRF of INIA),
were studied with the general objective of assessing the biodiversity of these landraces and to ascertain their value as genetic
resources for the development of germplasm adapted to the areas where they were collected with long and chilly winters. The
characterization study comprised 51 qualitative and 50 quantitative characters. Quantitative parameters were analyzed by Principal
Components Analysis (PCA). The 2-dimensional plot (49.3% of cumulative variability) formed a main group of accessions and
4 outliers (#1, #9, #27 and #28) separated in the first PC. The characters with a higher contribution to the first PC were
inflorescence length, leaf petiole length and leaf central foliole area. The presence of alkaloids, the percentage of plants
killed by soil borne fungal diseases, the phenology, the yield per plant and yield components were also assessed. Twenty six
accessions (the main group in the PCA plot) showed high homogeneity, with the following highlights: bitterness, indeterminate
growth habit, early ripeness and spring sowing with the exception of #18, in which seeding date is unknown and it had a later
phenology. By contrast accessions #9 and #27 were bitter of autumn sowing with determinate growing habit and they had the
longest values of primary inflorescence length and a later phenology when they were sown in spring. Average values for yield
and yield components showed a broad range of variation between accessions. The main yield component was the number of pods
per plant. Accession #22 had the highest mean seed mass, although this had not significant influence in yield. Accession #17
showed the highest yield and #1 the lowest. This last also had the lowest values of inflorescence length, leaf petiole length
and leaf central foliole area. No significant differences of resistance to soil-borne fungi were found between accessions.
The year had a significant effect in the phenology, yield and yield components except for number of seeds per pod. The studied
material might be of interest for the development of spring sowing germplasm adapted to north Iberian peninsula. 相似文献
4.
Martín-Cabrejas MA Ariza N Esteban R Mollá E Waldron K López-Andréu FJ 《Journal of agricultural and food chemistry》2003,51(5):1254-1259
The effect of different conditions of pea germination on dietary fiber (DF) composition was studied. Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) were subjected to acid hydrolysis, and the resultant neutral sugars, uronic acids, and Klason lignin were quantified. Germinated peas exhibited significantly higher contents of total dietary fiber (TDF) than the raw sample, due to the increases of both DF fractions. Under darkness conditions, germination exhibited the highest contents of IDF and SDF. Decreasing IDF/SDF ratios showed that the carbohydrate changes did not take place to the same extent during germination, the SDF fraction being the most affected. The detailed chemical composition of fiber fractions reveals increases of cellulose in the IDF of germinated samples, whereas SDF exhibits a decrease of pectic polysaccharides and also increases of polysaccharides rich in glucose and mannose. The DF results were corroborated by a comparative examination of the cell wall carbohydrate composition. 相似文献
5.
R. H. Andueza-Noh M. L. Serrano-Serrano M. I. Chacón Sánchez I. Sanchéz del Pino L. Camacho-Pérez J. Coello-Coello J. Mijangos Cortes D. G. Debouck J. Martínez-Castillo 《Genetic Resources and Crop Evolution》2013,60(3):1069-1086
The Mesoamerican (MA) gene pool of lima bean (Phaseolus lunatus L.) is widely distributed from northern Mexico to northern Argentina in its wild forms and from the southern United States to the east coast of Brazil in its domesticated forms. This broad distribution and lack of wild accessions of the MA gene pool in many areas of its natural distribution has impeded determining its center of domestication and establishing whether it has a single or multiple centers. To answer these questions, we evaluated 262 accessions of P. lunatus using two intergenic spacers of chloroplast DNA: atpB-rbcL and trnL-trnF. The data were analyzed using a maximum likelihood tree (ML), a haplotype network and two estimators of genetic differentiation (N ST and G ST). Nucleotide diversity (π) and haplotype (Hd) were quantified to estimate the percentage of reduction in genetic diversity (%r) as a founder effect. The ML tree and haplotype network indicated the existence of three groups (AI, MI and MII), which was supported by the high values of N ST (0.61–0.80). Values for %r were high (58.67–60.83 %). Existence of Mesoamerican and Andean gene pools was confirmed, with two genetically and geographically distinct groups (MI and MII) within the MA gene pool. We present the first evidence for multiple origins of domestication for the MA gene pool. For MI, we propose western central Mexico as the domestication area and between Guatemala and Costa Rica for MII. We observed a founder effect in the MA gene pool as a result of domestication. 相似文献
6.
Iglesias MT De Lorenzo C Del Carmen Polo M Martín-Alvarez PJ Pueyo E 《Journal of agricultural and food chemistry》2004,52(1):84-89
With the aim of finding methods that could constitute a solid alternative to melissopalynological and physicochemical analyses to determine the botanical origin (floral or honeydew) of honeys, the free amino acid content of 46 honey samples has been determined. The honeys were collected in a small geographic area of approximately 2000 km(2) in central Spain. Twenty-seven honey samples were classified as floral and 19 as honeydew according to their palynological and physicochemical analyses. The resulting data have been subjected to different multivariant analysis techniques. One hundred percent of honey samples have been correctly classified into either the floral or the honeydew groups, according to their content in glutamic acid and tryptophan. It is concluded that free amino acids are good indicators of the botanical origin of honeys, saving time compared with more tedious analyses. 相似文献
7.
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8.
A. San Bautista S. López-Galarza A. Martínez B. Pascual J. V. Maroto 《Journal of plant nutrition》2013,36(9):1527-1539
To determine their influence on leaf tipburn incidence and yields six nutrient solutions with different proportions of potassium (K), calcium (Ca), and magnesium (Mg) were tested in ‘Camarosa’ strawberry plants. Response models were made to predict tipburn incidence, yields and fruit weight. A high Ca proportion in the nutrient solution was determinant for high yields in the first season, while a high Mg content was fundamental for high marketable yields during the two last seasons. In 2001 and 2002, the average fruit weight was higher with high Mg levels, and in 2000 the lowest fruit weights coincided with low levels of Ca in the nutrient solution. The models for tipburn incidence in 2000 and 2002 indicated that solutions with intermediate to high levels of Mg and intermediate to low levels of Ca resulted in a more frequent incidence of tipburn. Conversely, in 2001, the highest tipburn incidence appeared with high K contents. 相似文献
9.
A. Madueño-Molina D. García-Paredes J. Martínez-Hernández R. Bugarín-Montoya J. I. Bojórquez-Serrano 《Journal of plant nutrition》2013,36(11):1701-1710
The objective of this study was to evaluate the effects of induced drought conditions and phosphorous (P) application on osmotic adjustment as reflected in the accumulation of organic solutes in the leaves of frijolillo. The experiment took place under greenhouse conditions without climate control. Plastic containers were used measuring 20 cm high × 15 cm in diameter. In each container, five plants were evaluated from emergence to vegetative growth phase. Three soil moisture regimes were evaluated (25%, 50%, and 100% of field capacity) combined with four concentrations of phosphorous (0, 50,100 and 150 mg kg?1 of soil). A completely randomized block design with a factorial arrangement of 3×4 with four replications was used. The cellular osmotic adjustment as a response to drought stress in frijolillo was associated with the accumulation of sugars, amino acids and proline in that higher concentrations than the control were measured with moisture at 25%. Concentrations of chlorophyll and carotene increased as soil moisture levels decreased. 相似文献
10.
Since the late 1980s, a large number of depsipeptides that contain a new topography, referred to as “head-to-side-chain” cyclodepsipeptides, have been isolated and characterized. These peptides present a unique structural arrangement that comprises a macrocyclic region closed through an ester bond between the C-terminus and a β-hydroxyl group, and terminated with a polyketide moiety or a more simple branched aliphatic acid. This structural pattern, the presence of unique and complex residues, and relevant bioactivity are the main features shared by all the members of this new class of depsipeptides, which are reviewed herein. 相似文献