Uptake of residual phosphate and freshly applied diammonium phosphate by Lolium perenne and Trifolium repens     

Anne Gallet  Ren Flisch  Jean‐Pierre Ryser  Joseph Nsberger  Emmanuel Frossard  Sokrat Sinaj 《植物养料与土壤学杂志》2003,166(5):557-567

Residual fertilizer phosphorus (residual P) may significantly contribute to crop P nutrition. To test this hypothesis, a pot experiment was conducted with ryegrass (Lolium perenne) and clover (Trifolium repens) grown separately on three different soils which either had not received P fertilizer for at least nine years (0F) or had received P fertilizer equivalent to crop P off‐take (F). Soils in the pot experiment were given either none (0F, F) or a single rate of 15 mg P (kg soil)^–1 as diammonium phosphate (0F+DAP, F+DAP). In the treatments 0F+DAP and F+DAP DAP had been labeled with ³³PO₄ while in the treatments 0F and F the pool of available soil P had been labeled with carrier‐free ³³PO₄. This allowed estimating the quantities of P in plant dry matter that derived from native soil P, residual fertilizer P or fresh fertilizer P. Fourteen to 62 % of the P in the above ground biomass of white clover or perennial ryegrass were derived from residual P whereas 7 to 28 % were derived from freshly applied DAP. The proportion of P derived from residual P was correlated to the total amount of P fertilizer added to the soils, while the proportion of P derived from DAP was correlated to the concentration of P in the soil solution of the 0F and F soils.  相似文献   

A quantitative assessment of genetic erosion in ipecac (Psychotria ipecacuanha)     

Luiz de Oliveira  Ernane Ronie Martins 《Genetic Resources and Crop Evolution》2002,49(6):607-617

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Oxidative stability of fish and algae oils containing long-chain polyunsaturated fatty acids in bulk and in oil-in-water emulsions   总被引：2，自引：0，他引：2  

Frankel EN  Satué-Gracia T  Meyer AS  German JB 《Journal of agricultural and food chemistry》2002,50(7):2094-2099

The oxidative stability of long-chain polyunsaturated fatty acid (PUFA) and docosahexaenoic acid (DHA)-containing fish and algae oils varies widely according to their fatty acid composition, the physical and colloidal states of the lipids, the contents of tocopherols and other antioxidants, and the presence and activity of transition metals. Fish and algal oils were initially much more stable to oxidation in bulk systems than in the corresponding oil-in-water emulsions. The oxidative stability of emulsions cannot, therefore, be predicted on the basis of stability data obtained with bulk long-chain PUFA-containing fish oils and DHA-containing algal oils. The relatively high oxidative stability of an algal oil containing 42% DHA was completely lost after chromatographic purification to remove tocopherols and other antioxidants. Therefore, this evidence does not support the claim that DHA-rich oils from algae are unusually stable to oxidation. Addition of ethylenediaminetetraacetic acid (EDTA) prevented oxidation of both fish and algal oil emulsions without added iron and at low iron:EDTA molar concentrations. EDTA, however, promoted the oxidation of the corresponding emulsions that contained high iron:EDTA ratios. Therefore, to be effective as a metal chelator, EDTA must be added at molar concentrations higher than that of iron to inhibit oxidation of foods containing long-chain PUFA from either fish or algae and fortified with iron.  相似文献   

Comparison of CLPP and enzyme activity assay for functional characterization of bacterial soil communities     

Anne Winding  Niels Bohse Hendriksen 《Journal of Soils and Sediments》2007,7(6):411-417

Background, Aims and Scope  

Functional characterization of soil microbial communities by the use of BIOLOG GN microtiter plates was compared with an optimized assay of measuring the enzymatic activity of bacterial associated enzymes. Since the first use of BIOLOG GN microtiter plates for characterization of environmental microorganisms, this Community Level Physiological Profile (CLPP) has been widely used and is today routinely used in soil monitoring programmes in e.g. the Netherlands (Nielsen and Winding 2002). The CLPP method is based upon the metabolic capabilities of bacteria during growth in the wells of the microtiter plates at nutrient rich conditions compared to the conditions in soil. Inoculum preparation, incubation conditions, reading intervals and data treatment have all been the subject of many investigations. In spite of the various criticisms, the method remains to be widely used, to a large extent due to the ease and speed of performance. The Enzymatic Activity Assay (EAA) is based on enzymatic cleavage of model fluorogenic enzyme substrates (4-methylumbelliferyl, MUF), that upon cleavage forms a fluorescent product. The assay is independent of bacterial growth and can be used directly on bacteria extracted from soil, yielding a functional characterization of the bacterial communities based on the enzymatic activities. The substrates chosen here represent 14 different enzymes related to the degradation of different carbohydrates, including starch, chitin and cellulose.  相似文献   

Size makes a difference     

Matthiessen J  Fagt S  Biltoft-Jensen A  Beck AM  Ovesen L 《Public health nutrition》2003,6(1):65-72

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Molecular characterisation of cultivars of apple (Malus × domestica Borkh.) using microsatellite (SSR and ISSR) markers     

Luís Goul?o  Cristina M. Oliveira 《Euphytica》2001,122(1):81-89

In this study, two microsatellite-based methodologies (SSR and ISSR) were evaluated for potential use in fingerprinting and determination of the similarity degree between 41 commercial cultivars of apple previously characterised using RAPD and AFLP markers. A total of 13 SSR primer sets was used and 84 polymorphic alleles were amplified. Seven ISSR primers yielded a total of 252 bands, of which 176 (89.1%) were polymorphic. Except for cultivars obtained from somatic mutations, all cultivars were easily distinguishable employing both methods. The similarity coefficient between cultivars ranged from 0.20 to 0.87 for SSR analysis and from 0.71 to 0.92 using the ISSR methodology. Dendrograms constructed using UPGMA cluster analysis revealed a phenetic classification that emphasises the existence of a narrow genetic base among the cultivars used, with the Portuguese cultivars revealing higher diversity. This study indicates that the results obtained based on the RAPD, AFLP, SSR and ISSR techniques are significantly correlated. The marker index, based on the effective multiplex ratio and expected heterozygosity, was calculated for both analyses (MI = 1.7 for SSR and MI = 8.4 for ISSR assays) and the results obtained were directly compared with previous RAPD and AFLP data from the same material. The SSR and ISSR markers were found to be useful for cultivar identification and assessment of phenetic relationships, revealing advantages, due to higher reproducibility, over other commonly employed PCR-based methods, namely RAPD and AFLP. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Production of interspecific F1 hybrids, BC1, BC2 and BC3 populations between Lycopersicon esculentum and two accessions of Lycopersicon peruvianum carrying new root-knot nematode resistance genes     

Sami Doganlar  Anne Frary  Steven D. Tanksley 《Euphytica》1997,95(2):203-207

Two accessions of Lycopersicon peruvianum Mill. (PI270435, PI126443) carrying Mi-2 and Mi-3, respectively, new root-knot nematode resistance genes, were selected as the male parents for crosses with L. esculentum Mill. in order to produce interspecific hybrids. Crossability barriers between these two distantly related species were circumvented by ovule culture. A total of ten interspecific F₁ hybrid plants were produced. The hybrid nature of the putative F₁ plants was confirmed by a comparison of several morphological characteristics and a PCR-based assay. Eight of ten hybrid plants were backcrossed with L. esculentum to generate a total of 98 BC₁ progeny. Two lines were advanced to the BC₂ and BC₃ levels. Based on these results, ovule culture was found to be an effective method for the production of novel interspecific F₁ and BC₁ plants. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Comparative fine mapping of fruit quality QTLs on chromosome 4 introgressions derived from two wild tomato species   总被引：6，自引：0，他引：6  

Heather E. Yates  Anne Frary  Sami Doganlar  Anna Frampton  Nancy T. Eannetta  John Uhlig  Steven D. Tanksley 《Euphytica》2004,135(3):283-296

Despite their unsuitability for agricultural production, the wild relatives of crop species represent a largely untapped resource of novel QTLs potentially useful for crop plant improvement. In this regard, previous introgression studies, involving several different wild tomato species, have shown that the long arm of chromosome 4 contains QTLs for many horticulturally important traits including soluble solids content, fruit shape, lycopene content and biochemical composition. However, these earlier studies were unable to determine how many genes control these traits and whether genes affecting the same character from different wild species are allelic or not. In an effort to shed light on these issues,we have constructed a series of lines containing small, overlapping introgressions for portions of the long arm of chromosome 4 from L. peruvianum and L. hirsutum and tested these lines in replicated field trials. The results provide evidence for multiple, non-allelic loci controlling soluble solids and fruit weight. They also show that the loci controlling some traits (e.g. fruit shape, fruit weight, epidermal reticulation) co-localize to the same portions of chromosome 4, a result that maybe attributed to pleiotropy and/or gene dense areas with lower than average recombination. The implications of these finding for molecular breeding and utilization of exotic germplasm are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Knowledges of the creative economy: Towards a relational geography of diffusion and adaptation in Asia     

Lily Kong  Chris Gibson  Louisa‐May Khoo  Anne‐Louise Semple 《Asia Pacific viewpoint》2006,47(2):173-194

Abstract: Recent dialogues in geography and the social sciences have reminded researchers of the extent to which academic and policy knowledges are socially and spatially embedded – that is, they circulate through formal and informal systems of publishing, exchange, commodification and cultural influence. Academic and policy knowledges are, in short, very much a part of the creative economy. In light of this, our paper surveys knowledges of the creative economy itself, as reflected in a geography of industry reports and government policy statements in selected Asian countries. Using a post‐positivist framework adapted from diffusion theory, we critically interpret the circulation, mutation and adaptation of knowledges of the creative economy, claims to its significance, areas of emphases and notable silences.  相似文献   

Genotype selection by REML/BLUP methodology in a segregating population from an interspecific Passiflora spp. crossing     

Eileen Azevedo Santos  Alexandre Pio Viana  Josie Cloviane de Oliveira Freitas  Daniele Lima Rodrigues  Rulfe Ferreira Tavares  Claudia Lougon Paiva  Margarete Magalhães Souza 《Euphytica》2015,202(1):1-11

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