The fate of C-naphthalene in soil microcosms containing Scots pine seedlings and enchytraeids

The fate of freshly spiked and aged ¹⁴C-naphthalene associated residues as investigated in the presence and absence of ectomycorrhizal Scots pine seedlings and enchytraeid worms, in a factorial experimental design. Microcosms were used which enabled the ¹⁴C-labelled naphthalene associated residues to be quantified, including plant lipids which acted as an additional naphthalene sink within the microcosms. The presence of plant roots altered the availability of the ¹⁴C-naphthalene and associated residues to degrading microbes. Mineralisation and volatilisation of ¹⁴C naphthalene in freshly spiked soil were lower in the presence of Scots pine. Conversely, in soil aged for 180 d, Scots pine increased mineralisation, and bioavailability of naphthalene. Root-mediated processes, microbial activity and enchytraeids interact with desorption, bioavailability and mineralisation of naphthalene.     

Secular and socio-economic trends in compliance with dietary targets in the north Glasgow MONICA population surveys 1986-1995: did social gradients widen?

OBJECTIVE: To compare trends in the consumption of key foods over 10 years in the most deprived and least deprived quarters in north Glasgow, Scotland as defined by the Carstairs deprivation index for their postcode of domicile. DESIGN: Four random, cross-sectional, age- and gender-stratified population surveys carried out in 1986, 1989, 1992 and 1995. After assigning a deprivation score, food-frequency questionnaires from 2883 men and 3127 women were examined for compliance with dietary targets, examining trends by gender and within the most and least deprived quarters of the population. SETTING: North Glasgow, Scotland. SUBJECTS: Over 600 men and 600 women (aged 25-64 years) in each of the four survey years who completed a lifestyle questionnaire including a food frequency section. RESULTS: Increasing trends in the reported consumption of fruit and vegetables and oil-rich fish were observed over the 10-year period. However, the trend to increased fruit and vegetable consumption in the most deprived groups was not significant, and in 1995 only 8% of men and 12% of women in this group claimed consumption of these foods 4 or more times a day. In general, a higher percentage of those in the least deprived group met the targets for the key foods. CONCLUSIONS: Trends to increasing consumption of fruit and vegetables and fish were in the right direction, but the targets for consumption of certain key foods were met by a minority of the population. The progress towards the target for fruit and vegetables showed widening social gradients with time.     

Assessment of strawberry aroma through SPME/GC and ANN methods. Classification and discrimination of varieties

To provide an efficient and running analytical tool to strawberry plant breeders who have to characterize and compare the aromatic properties of new cultivars to those already known, a HS-SPME/GC-MS analysis method has been coupled with a statistical treatment method issued from the current development of artificial neuron networks (ANN), and more specifically, the unsupervised learning systems called Kohonen self-organizing maps (SOMs). So, 70 strawberry samples harvested at CIREF from 17 known varieties have been extracted by using a DVB/Carboxen/PDMS SPME fiber according to the headspace procedure, and then chromatographed. A panel of 23 characteristic aromatic constituents has been selected according to published results relative to strawberry aroma. The complex resulting matrix, collecting the relative abundance of the 23 selected constituents for each sample, has been input into the SOM software adapted and optimized from the Kohonen approach described by one of the authors. After a period of training, the self-organized system affords a map of virtual strawberries to which real samples are compared and plotted in the best matching unit (BMU) of the map. The efficiency for discriminating the real samples according to their variety is dependent on the number of units selected to define the map. In this case, a 24-unit map allowed the complete discrimination of the 17 selected varieties. Moreover, to test the validity of this approach, two additional samples were blind-analyzed and the results were computed according to the same procedure. At the end of this treatment, both samples were plotted into the same unit as those of the same variety used for training the map.     

NMR and HPLC-UV profiling of potatoes with genetic modifications to metabolic pathways

Metabolite profiling has been carried out to assess the compositional changes occurring in potato tubers after genetic modifications have been made to different metabolic pathways. Most major features in the (1)H NMR and HPLC-UV profiles of tuber extracts have been assigned. About 40 GM lines and controls belonging to 4 groups of samples (derived from cv. Record or cv. Desirée and modified in primary carbon metabolism, starch synthesis, glycoprotein processing, or polyamine/ethylene metabolism) were analyzed. Differences were assessed at the level of whole profiles (by PCA) or individual compounds (by ANOVA). The most obvious differences seen in both NMR and HPLC-UV profiles were between the two varieties. There were also significant differences between two of the four Desirée GM lines with modified polyamine metabolism and their controls. Compounds notably affected were proline, trigonelline, and numerous phenolics. However, that modification gave rise to a very abnormal phenotype. Certain lines from the other groups had several compounds present in significantly higher or lower amounts compared to the control, but the differences in mean values amounted to no more than a 2-3-fold change: in the context of variability in the whole data set, such changes did not appear to be important.     

Soil microbial community composition and land use history in cultivated and grassland ecosystems of coastal California

Phospholipid ester-linked fatty acid (PLFA) profiles were used to evaluate soil microbial community composition for 9 land use types in two coastal valleys in California. These included irrigated and non-irrigated agricultural sites, non-native annual grasslands and relict, never-tilled or old field perennial grasslands. All 42 sites were on loams or sandy loams of similar soil taxa derived from granitic and alluvial material. We hypothesized that land use history and its associated management inputs and practices may produce a unique soil environment, for which microbes with specific environmental requirements may be selected and supported. We investigated the relationship between soil physical and chemical characteristics, management factors, and vegetation type with microbial community composition. Higher values of total soil C, N, and microbial biomass (total PLFA) and lower values of soil pH occurred in the grassland than cultivated soils. The correspondence analysis (CA) of the PLFA profiles and the canonical correspondence analysis (CCA) of PLFA profiles, soil characteristics, and site and management factors showed distinct groupings for land use types. A given land use type could thus be identified by soil microbial community composition as well as similar soil characteristics and management factors. Differences in soil microbial community composition were highly associated with total PLFA, a measure of soil microbial biomass, suggesting that labile soil organic matter affects microbial composition. Management inputs, such as fertilizer, herbicide, and irrigation, also were associated with the distinctive microbial community composition of the different cultivated land use types.     

Morphological and molecular diversity of Nordic oat through one hundred years of breeding

Summary Genetic diversity in microsatellites and development of agronomical characters in Nordic oat cultivars (Avena sativa) from the 20th century, ranging from landraces to new cultivars, were studied. A clear development in agronomical characters has taken place in this period: Straw length has been reduced, harvest index has increased and heading date has declined. The persistent oat breeding effort in the northern part of the region was indicated by the data, since cultivars from this region showed higher harvest index. Also adaptation to shorter summers was apparent in cultivars from the most northern part of the area. When comparing cultivars released after 1940 to the landraces, the loss of diversity revealed for the agronomical characters was also indicated by the molecular data. This indicates that a more general loss of diversity has taken place in the period, possibly due to random factors during the breeding process (bottleneck effect). The reduction in diversity revealed by recent cultivars at an agronomical as well as a molecular level emphasises the importance of implementing a conservation strategy for older material in order to secure genetic diversity for future oat breeding efforts.     

Performance of Timothy-based Grass/Legume Mixtures in Cold Winter Region

This study sought to identify grass/legume mixtures that increase the yield and persistence of forage stands with improved nutritive quality in cold‐winter regions, compared with the standard mixture of timothy (Phleum pratense L.)/red clover (Trifolium pratense L.)/alsike clover (Trifolium hybridum L.). Timothy was mixed with either perennial ryegrass (Lolium perenne L.), meadow fescue (Festuca pratensis L.) or Kentucky bluegrass (Poa pratensis L.). The legumes in mixtures were red clover, alfalfa (Medicago sativa L.) or white clover (Trifolium repens L.). Averaged over three production years, the majority of mixtures had greater dry matter (DM) yields than the standard (8.35 t ha^?1). Timothy, grown alone and in three mixtures, outyielded the standard by 19–30 %. Yield reductions in mixtures over the 3‐year period were greatest with red clover, and least with bluegrass. Mixtures with alfalfa were highest in nitrogen (28.4 g kg^?1), while grasses grown alone (24.6 g kg^?1) and the standard mixture (25.1 g kg^?1) were the lowest in N. Mixtures with red clover or alfalfa had the least neutral detergent fibre (NDF), averaging 418 and 429 g kg^?1 respectively. Mixtures including white clover were initially low in NDF at 347 g kg^?1 in year 1 but increased to 550 g kg^?1 in year 3 as white clover composition declined in the sward.     

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

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.     

Extraction and determination of glucosinolates from soil

The use of glucosinolate-containing plants as soil-incorporated biofumigants for pest and disease control has raised questions regarding the fate of glucosinolates in soil; however, no method for routine analysis of glucosinolates in soil has been reported. A simple method to extract glucosinolates from soil with quantification as desulfoglucosinolates by HPLC is presented. The method involves two extractions with 70% methanol at room temperature, centrifugation, and filtration prior to the desulfation step. The desulfoglucosinolates are then quantified by HPLC using established protocols for plant tissue analysis. There were no significant interfering peaks from the soil extracts, and the method provided high extraction efficiencies (around 100%) for both aromatic (benzyl) and aliphatic (2-propenyl) glucosinolates when amended at a wide range of realistic field soil concentrations (1.6-120 nmol/g of soil). The method was equally effective in three diverse Australian soils that varied in organic matter, clay content, and pH. The method was effective in air-dried or field-moist soil, although evidence for rapid glucosinolate degradation in field-moist soil indicates that extraction of moist soils should be performed as soon as possible after sampling. The method is compatible with field soil sampling at remote sites and utilizes the same equipment and protocols already established for plant tissue analysis. Extraction of glucosinolates in the field following incorporation of Indian mustard (Brassica juncea) and rape (Brassica napus) green manure crops was also tested. Eight different glucosinolates contained in the plant tissues were identified and quantified in soil extracts at concentrations ranging from 0.11 to 21.7 nmol/g of soil.