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121.
Barbara Laddomada Miriana Durante Giacomo Mangini Leone D’Amico Marcello Salvatore Lenucci Rosanna Simeone Luciana Piarulli Giovanni Mita Antonio Blanco 《Genetic Resources and Crop Evolution》2017,64(3):587-597
Phenolic acid intake through the consumption of whole-wheat foods provides important health benefits associated with reduced risks of cardiovascular diseases and colon cancer. The genetic variation for phenolic acids was extensively studied in common wheat, but a comprehensive survey in tetraploid wheat is lacking. In this study we evaluated the genetic variability for individual and total phenolic acids concentration existing in a large collection of tetraploid wheat (Triticum turgidum L.). A 2-year evaluation was undertaken on the whole-meal flour of 111 genotypes belonging to seven T. turgidum subspecies including cultivars, landraces and wild accessions. Durum cultivars [T. turgidum subsp. durum (Desf.) MacKey], had the highest average concentration of total phenolic acids (828.7 μg g?1 dm in 2012; 834.5 μg g?1 dm in 2013) with amounts varying from 550.9 μg g?1 dm to 1701.2 μg g?1 dm, indicating a variation of greater than threefold fold. The lowest concentration of phenolic acids was found in T. turgidum subsp. dicoccum (Schrank ex Schübler) Thell. Rivet wheat (T. turgidum L. subsp. turgidum) had phenolic acid concentrations similar to those in durum, but less variation was noted among the accessions. On the other hand, the accessions of the four remaining subspecies showed lower phenolic acid concentrations and variation among the accessions as compared to durum. A total of six phenolic acids were identified across the wheat genotypes. The effects of genotype, year and year × genotype were estimated by ANOVA and resulted significant for all phenolic acids. The ratio of genotypic variance to total variance suggested the possibility of improving phenolic acid content in elite wheat germplasm through appropriate breeding programs. Moreover, significant correlations between phenolic acids and other quality characteristics of the grain were detected. 相似文献
122.
Forest structure and live aboveground biomass variation along an elevational gradient of tropical Atlantic moist forest (Brazil) 总被引:1,自引:0,他引:1
Luciana F. Alves Simone A. Vieira Marcos A. Scaranello Plinio B. Camargo Flavio A.M. Santos Carlos A. Joly Luiz A. Martinelli 《Forest Ecology and Management》2010
Live aboveground biomass (AGB) is an important source of uncertainty in the carbon balance from the tropical regions in part due scarcity of reliable estimates of live AGB and its variation across landscapes and forest types. Studies of forest structure and biomass stocks of Neotropical forests are biased toward Amazonian and Central American sites. In particular, standardized estimates of aboveground biomass stocks for the Brazilian Atlantic forest are rarely available. Notwithstanding the role of environmental variables that control the distribution and abundance of biomass in tropical lowland forests has been the subject of considerable research, the effect of short, steep elevational gradients on tropical forest structure and carbon dynamics is not well known. In order to evaluate forest structure and live AGB variation along an elevational gradient (0–1100 m a.s.l.) of coastal Atlantic Forest in SE Brazil, we carried out a standard census of woody stems ≥4.8 cm dbh in 13 1-ha permanent plots established on four different sites in 2006–2007. Live AGB ranged from 166.3 Mg ha−1 (bootstrapped 95% CI: 144.4,187.0) to 283.2 Mg ha−1 (bootstrapped 95% CI: 253.0,325.2) and increased with elevation. We found that local-scale topographic variation associated with elevation influences the distribution of trees >50 cm dbh and total live AGB. Across all elevations, we found more stems (64–75%) with limited crown illumination but the largest proportion of the live AGB (68–85%) was stored in stems with highly illuminated or fully exposed crowns. Topography, disturbance and associated changes in light and nutrient supply probably control biomass distribution along this short but representative elevational gradient. Our findings also showed that intact Atlantic forest sites stored substantial amounts of carbon aboveground. The live tree AGB of the stands was found to be lower than Central Amazonian forests, but within the range of Neotropical forests, in particular when compared to Central American forests. Our comparative data suggests that differences in live tree AGB among Neotropical forests are probably related to the heterogeneous distribution of large and medium-sized diameter trees within forests and how the live biomass is partitioned among those size classes, in accordance with general trends found by previous studies. In addition, the elevational variation in live AGB stocks suggests a large spatial variability over coastal Atlantic forests in Brazil, clearly indicating that it is important to consider regional differences in biomass stocks for evaluating the role of this threatened tropical biome in the global carbon cycle. 相似文献
123.
Seed-yield stability, frequently associated with drought-tolerance strategies, is one of the main breeding objectives for the development of crops for semi-arid mediterranean-type environments. Since breeding of new industrial crops targeted for arid lands is not appreciably different from that of traditional crops, higher yield is achieved by increased harvest-index, at the cost of losing traits associated with drought-tolerance and reduced seed-yield stability. Using Lesquerella as a model we compared selected and unselected accessions of annual (L. gracilis and L. angustifolia) and perennial (L. pinetorum and L. mendocina) genotypes grown in field experiments in Patagonia, Argentina. Our objective was to assess the effects of breeding for increased seed-yield on traits related to the main characteristics that define the most common ideotype for mediterranean-type environments: early vigor, conservative growth strategy post-anthesis and reserves storage. Our specific question was: Have any of the attributes associated with seed-yield stability been indirectly selected during the domestication process? Our results show that these characteristics were reduced or lost, in selected lines compared to their wild relatives. Early vigor was lower in selected accessions and was associated mainly with reduced relative growth rate and CO2 assimilation. During the reproductive period the growth strategy was changed by selection towards a non-conservative and more acquisitive resource use strategy. Traits associated with this strategy were linked to higher water use efficiency and growth capacity (higher CO2 assimilation rate, specific leaf area, and leaf allocation), but also with loss of structural adaptation to low resource environments (i.e. low specific leaf area), an increase in nutrient and water demands, and reduced nutrient use efficiency. Carbohydrates accumulation pre-anthesis was lower in selected accessions of all four species, and also, just in perennials we found lower reserves storage post-anthesis. These changes in the pattern of carbohydrates accumulation could be associated to lower seed-yield stability due to the loss of buffer capacity linked with the use of pre-anthesis reserves for seed filling. On the other hand, in perennial species lower reserves storage after seed harvest could reduce plant longevity and survival. We conclude that indirect changes occurred during the preliminary domestication of both annual and perennial species of Lesquerella used in our experiment. These changes were against those required if these species were to be developed as crops for semi-arid, mediterranean environments and should result in low seed-yield stability. 相似文献
124.
The development of perennial industrial crops could contribute to increase agriculture sustainability and yield stability in arid environments. Since perennial plants allocate resources preferentially to perpetuation and to structural and functional characters that provide drought tolerance, they tend to have lower reproductive output (yield) than their congeneric annuals. Four species of Lesquerella native to arid regions were evaluated to understand the relationships between reproduction, drought tolerance, and their association with the plant's life span. We assessed the following set of characters (defined as plant strategies): phenology, gas exchange, specific leaf area, leaf area ratio, total biomass and biomass allocation. Annual (Lesquerella gracilis and Lesquerella angustifolia) and perennial (Lesquerella mendocina and Lesquerella pinetorum) species were compared under water limiting conditions. Within this set of species differences in structural and functional characters were observed. The annual, L. gracilis showed a plant strategy characterized by high reproductive output, harvest index (HI) and specific leaf area (SLA). L. mendocina (perennial), produced more total biomass, but had a low reproductive output, and also showed characters that provide drought tolerance (high allocation to roots-root mass ratio (RMR), and storage-total non structural carbohydrates (TNC) and low SLA). The annual L. angustifolia and the perennial L. pinetorum had intermediate plant strategies (i.e. intermediate values of traits typically related with annual or perennial life span). In the case of L. pinetorum we found some traits common to L. mendocina: long vegetative period, high biomass, CO2 assimilation rate (A), and water use efficiency (WUE), and low SLA. The high reproductive output in L. pinetorum was a result of both, higher total biomass and longer growing season compared to the annuals, and of higher HI in relation to the other perennial. These differences in plant strategies among perennial Lesquerella show that there are different combinations of traits that could be used as criteria for the selection of a perennial crop in programs of domestication for Patagonia and others arid lands. 相似文献
125.
Bekris Fotios Georgescu Luciana Bariotakis Michael Kotzabasis Kiriakos Panopoulos Nickolas Pirintsos Stergios 《Journal of Soils and Sediments》2019,19(1):381-392
Journal of Soils and Sediments - Despite the important role of soil ammonia-oxidizing microorganisms (AOM) in the biogeochemical cycle of nitrogen, a unified view of the factors driving their... 相似文献
126.
Julio L. Lancelotti Luciana M. Pozzi Pablo M. Yorio María C. Diéguez Miguel A. Pascual 《水产资源保护:海洋与淡水生态系统》2010,20(1):1-8
- 1. Conflicts between habitat use and conservation are inherent to the management of wetlands. A major challenge for their management is to preserve habitat while addressing the demands from multiple users. In southern Patagonia (Argentina), a growing aquaculture activity based on rainbow trout introductions in shallow lakes is generating concerns about the effects on the waterbird fauna, including some endemic species.
- 2. Generalized linear models (GLM) were used to analyse data on the endemic hooded grebe (Podiceps gallardoi) collected over a diverse set of lakes to: (1) build presence‐absence models as a function of environmental variables; (2) assess current and potential overlap with trout aquaculture; (3) explore the power of alternative lake assignment algorithms based on habitat variables to segregate critical habitat and aquaculture activities; and (4) explore the correlation between the probability of grebe presence and their abundance in given lakes.
- 3. Hooded grebe presence is clearly correlated with macrophyte cover, lake area, and water conductivity. Medium size lakes, with a combination of emerging macrophytes, adjacent to open water areas had the highest probability of both hooded grebe presence and abundance.
- 4. Different lake allocation scenarios are identified that could grant significant protection to hooded grebes without substantial losses for trout producers. The a priori probability to hold hooded grebe, assigned by the model based on lake characteristics, provides a tool that can be used by managing authorities to derive precautionary management rules to regulate aquaculture and to preserve primary hooded grebe habitat. Copyright © 2009 John Wiley & Sons, Ltd.
127.
Renata Pereira da Silva-Marques Joanis Tilemahos Zervoudakis Luciana Keiko Hatamoto-Zervoudakis Pedro Ivo José Lopes da Rosa e Silva Núbia Bezerra do Nascimento Matos Andresa Lazzarotto Feliciano Rones Goulart de Paula Júnior Luciano da Silva Cabral 《Tropical animal health and production》2018,50(4):715-720
Supplementation of animals in the rainy season is essential to maximise weight gain. Thus, the objective was to evaluate the effects of supplementation with low-, medium- and high-protein levels on nutritional parameters of grazing beef cattle in the rainy season. Eight rumen-cannulated Nellore bulls (437 kg body weight) were used in a 4?×?4 double Latin square design with four supplements and four experimental periods. The treatments were mineral supplement (ad libitum) and supplements with low-protein (LPSU), medium-protein (MPS) and high-protein (HPS) levels, providing 106, 408 and 601 g/day of crude protein (CP), respectively. There was no difference (P?>?0.05) between treatments for dry matter and forage intake, ruminal pH, ruminal ammonia nitrogen (RAN) at time 0 (before supplementation) and microbial protein yield. Animals on MPS had a higher (P?>?0.05) intake and digestibility of CP, higher RAN levels (3 and 6 h after supplementation), increased nitrogen intake and a better nitrogen balance than animals on LPSU. The HPS provided higher (P?>?0.05) RAN at time 6 and a better nitrogen balance when compared with MPS. We therefore infer that the high-protein supplement positively impacts nitrogen metabolism and efficiency in grazing beef cattle during the rainy season. 相似文献
128.
Domingos Susan C. B. Carioca Júnior Herzem R. Lilenbaum Walter Santa Rosa Myrna T. Pereira Cynthia D. Medeiros Luciana S. 《Tropical animal health and production》2019,51(7):1801-1805
Tropical Animal Health and Production - The occurrence of Mycobacterium bovis infection in wildlife places at risk livestock, public health, and ecosystems that house endangered species. However,... 相似文献
129.
Comparison of a rapid immunochromatographic assay with an immunofluorescent antibody test for detection of Leishmania infantum antibodies in dogs
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130.
Souza Shenia O. Oliveira Luciana C. Cavagis Alexandre D. M. Botero Wander G. 《Water, air, and soil pollution》2014,225(12):1-13
Treated and untreated rice straw extensively exists in the soil. In order to elucidate its possible effect on the fate of organic pollutants, sorption of pyrene by rice straw and its main constituents (lignin, cellulose, and hemi-cellulose) were studied, as single solute and in the presence of other co-existing organic pollutants, phenanthrene (Phen), benzo[a]pyrene (BaP), phenol, and pentachlorophenol (PCP). Pyrene showed the greatest sorption on lignin with greater aromaticity and smaller polarity, and the sorption coefficient was almost two orders of magnitude greater than those on cellulose and hemi-cellulose. Bi-solute sorption results showed that Phen, BaP and PCP exhibited apparent competitive sorption with pyrene on the four sorbents; while the existence of phenol promoted the sorption of pyrene on rice straw and lignin but inhibited the sorption on cellulose and hemi-cellulose. For the two polycyclic aromatic hydrocarbon (PAH) co-solutes and PCP, hydrophobicity and molecular size played important roles in competition, suggesting the direct competition for hydrophobic sorption sites and pore blockage mechanisms. In contrast, the polar co-solute, phenol showed different effects on pyrene sorption onto the four sorbents, suggesting that multiple interactions between polar organic compounds and sorbents are involved in the sorption. 相似文献