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The discovery of bioactive components in foods is exciting, suggesting the possibility of improved public health through diet. Yet the content of bioactive components in plant food varies, making quality control and intake recommendations problematic. Variation in content of bioactive components in fruits and vegetables depends upon both genetics and environment, including growing conditions, harvest and storage, processing and meal preparation. Cruciferous vegetables, which contain both anticarcinogenic and antioxidant properties, are excellent examples to illustrate the problem in assessing health benefits of foods that vary in content of bioactive components. In broccoli, the content of both glucosinolates and their bioactive hydrolysis products varies with genotype, environment and processing. Antioxidant vitamins and flavonoid content varies also. Here we review the influences of genetics, environment and post-harvest processing on content of bioactive components in broccoli, an area that is presently only partly understood. Reporting a range for bioactive component content can help the public to make informed choices about diet. For the future, research into the mechanisms behind this variation can lead to an understanding of genetic regulation of these variations, resulting in the generation of a consistent supply of nutritionally enhanced plant foods on the market. [Copyright &y& Elsevier]

Examines patterns in the distribution of upland breeding birds in Great Britain. Level of regionalization of the birds; Habitat composition of the regions; Differences in the number and conservation importance of the bird assemblages.

Summary 1. The golden plover Pluvialis apricaria is of high conservation concern in Europe. Previous studies have concentrated on how birds utilize moorland. We used radio-telemetry to study their habitat selection and behaviour, during both night and day, in an upland landscape of enclosed fields and moorland in county Durham, UK. 2. During incubation adult golden plover fed principally in enclosed fields 1·1–3·7 km from their moorland nests, but spent less than 5% of their foraging time on moorland. In contrast, birds with broods spent around 85% of their time foraging on moorland. 3. Birds on moorland selected calcareous grassland and avoided old stands of dense tall heather (> c. 12 cm). Younger, shorter (< c. 5–8 cm), sparser heather was used as much as would be expected by chance. Mires of harestail cotton grass Eriophorum vaginatum , the dominant community type when heather Calluna vulgaris is heavily grazed, was selected on both moorland sites. 4. Only 17 of 85 fields in the study area were used for foraging by breeding golden plover. The number of molehills, a reported indicator of earthworm abundance, was the best single variable explaining field choice. Both field size and distance from road had small but significant effects on field choice. 5. We advocate that groups of enclosed fields regularly used by golden plover during the breeding season be afforded specific protection under conservation schemes (e.g. environmentally sensitive area agreements). Conservationists wishing to locate such fields should look for areas with high earthworm populations, as indicated by molehills, close (< 4 km) to breeding populations of golden plover. Rank heather on flat or gently sloping ground should be kept short by appropriate burning or grazing. Areas of calcareous grassland should be preserved. 6. These data illustrate the value of detailed radio-telemetry in informing equally detailed habitat management for important bird species. [ABSTRACT FROM AUTHOR]

Abstract: The papermaking properties of 22 pure and hybrid poplars are being evaluated in an on-going investigation. Twenty of the poplars were harvested after 7.5 years from three different sites in the Midwestern and North Central US. The other 2 poplars survived at only two of three sites (64 total samples). The Crandon hybrid had the highest growth rate (tha−1 y−1) and wood density (both averaged across the 3 sites). This poplar had a high cellulose content (compared to the average), a low lignin content and produced bleached kraft fibers at a high yield (wt.% on wood chips). Further, this poplar responded very well to kraft pulping and oxygen delignification and bleached to the highest final brightness ever observed in our laboratory (94.5% Elrepho). It also produced an 18 kappa number unbleached pulp with <0.5% rejects in only two-thirds the time required for sugar maple (Acer saccharum). We also report on clone 220-5 that had the highest area-weighted average microfibril angle. Pulps from this poplar had excellent tensile properties and further improvements are expected with 1–2 years of additional growth that should result in a small, but significant increase in average fiber length. Some results are also presented for clone 313.55 and aspen (Populus tremuloides) to demonstrate the many substantial benefits that can be accrued from proper wood selection. [Copyright &y& Elsevier]