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Xiaofang Wang Thomas D. Warkentin Colin J. Briggs B. Dave Oomah Clayton G. Campbell Sheila Woods 《Euphytica》1998,101(1):97-102
Seed samples of seventeen field pea cultivars grown at five locations, and nine grass pea lines grown at two locations, in
western Canada during 1993 and 1994 were analysed for total phenolics and condensed tannins. Each location in each year was
considered as one environment. Total phenolics in field pea differed significantly among cultivars, ranging from 162 mg/kg
DM (dry matter) (CE, catechin equivalents) for AC Tamor to 325 mg/kg DM (CE) for Richmond. Field pea had barely detectable
levels of condensed tannins. Total phenolics in grass pea ranged from 868 mg/kg DM (CE) for L880388 to 2059 mg/kg DM (CE)
for LS89110. Condensed tannins in grass pea ranged from 0.89 g/kg DM (CE) for L880388 to 5.18 g/kg DM (CE) for LS89125. Cultivar
had a larger relative contribution to total phenolic levels in field pea and to total phenolic and condensed tannin levels
in grass pea than environment. Total phenolic and condensed tannin levels were not correlated with seed yield and seed protein
content in field pea or grass pea. Levels of total phenolics and condensed tannins were positively correlated in grass pea.
Grass pea seeds with darker seed coat colour contained higher levels of condensed tannins.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
164.
Summary Phenolic acid contents were determined in seeds from five buckwheat cultivars grown at three locations in western Canada for four years. Buckwheat contained 12–16 g/kg of total phenolic acids, about 3 g/kg of esterified phenolic acids, and 8–13 g/kg of etherified phenolic acids. The latter represented 70 to 79% of the total phenolics. Variation in phenolic acids was mainly due to cultivar, seasonal effects and their interaction, while growing location had no significant effect. Phenolic acid contents of buckwheat were independent of seed color and protein content. Esterified phenolic acids exhibited a negative significant association with etherified phenolic acids in buckwheat. 相似文献
165.
Will J. Peach Steve Dodd Duncan B. Westbury Simon R. Mortimer Paul Lewis Alex J. Brook Stephanie J. Harris Rebecca Kessock-Philip Dave L. Buckingham Keith Chaney 《Biological conservation》2011,(2):836-850
Declines of farmland birds have been pronounced in landscapes dominated by lowland livestock production and densities of seed-eating birds are particularly low in such areas. Modern livestock production often entails a simple cropping system dominated by ley grassland and maize grown for animal feed. These crops often lack invertebrate and seed resources for foraging birds and can be hostile nesting environments. Cereal-based wholecrop silages (CBWCS) offer potential benefits for farmland birds because they can be grown with minimal herbicide applications and can be spring-sown with following winter stubbles. We compared the biodiversity benefits and agronomic yields of winter-sown wheat and spring-sown barley as alternatives to grass and maize silage in intensive dairy livestock systems. Seed-eating birds foraged mainly in CBWCS fields during summer, and mainly on barley stubbles during winter and this reflected the higher densities of seed-bearing plants therein. Maize and grass fields lacked seed-bearing vegetation and were strongly avoided by most seed-eating birds. Production costs of CBWCS are similar to those of maize and lower than those of grass silage. Selective (rather than broad-spectrum) herbicide application on spring barley crops increased forb cover, reduced yields (by 11%) but caused only a small (<4%) increase in production costs. CBWCS grown with selective herbicide and with following winter stubbles offer a practical conservation measure for seed-eating farmland birds in landscapes dominated by intensively-managed grassland and maize. However, the relatively early harvesting of CBWCS could destroy a significant proportion of breeding attempts of late-nesting species like corn bunting (Emberiza calandra) or yellow wagtail (Motocilla flava). Where late-breeding species are likely to nest in CBWCS fields, harvesting should be delayed until most nesting attempts have been completed (e.g. until after 1st August in southern Britain). 相似文献
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Anthropogenic noise exposure in protected natural areas: estimating the scale of ecological consequences 总被引:1,自引:0,他引:1
Jesse R. Barber Chris L. Burdett Sarah E. Reed Katy A. Warner Charlotte Formichella Kevin R. Crooks Dave M. Theobald Kurt M. Fristrup 《Landscape Ecology》2011,26(9):1281-1295
The extensive literature documenting the ecological effects of roads has repeatedly implicated noise as one of the causal
factors. Recent studies of wildlife responses to noise have decisively identified changes in animal behaviors and spatial
distributions that are caused by noise. Collectively, this research suggests that spatial extent and intensity of potential
noise impacts to wildlife can be studied by mapping noise sources and modeling the propagation of noise across landscapes.
Here we present models of energy extraction, aircraft overflight and roadway noise as examples of spatially extensive sources
and to present tools available for landscape scale investigations. We focus these efforts in US National Parks (Mesa Verde,
Grand Teton and Glacier) to highlight that ecological noise pollution is not a threat restricted to developed areas and that
many protected natural areas experience significant noise loads. As a heuristic tool for understanding past and future noise
pollution we forecast community noise utilizing a spatially-explicit land-use change model that depicts the intensity of human
development at sub-county resolution. For road noise, we transform effect distances from two studies into sound levels to
begin a discussion of noise thresholds for wildlife. The spatial scale of noise exposure is far larger than any protected
area, and no site in the continental US is free form noise. The design of observational and experimental studies of noise
effects should be informed by knowledge of regional noise exposure patterns. 相似文献
168.
PS Ie D Petros DH Stinner PL Phelan B Hamaker KW Koelling Y Vodovotz 《Journal of agricultural and food chemistry》2012,60(36):9229-9235
The objective of this study was to compare gelatinization properties and molecular composition of starches extracted from locally grown organic and conventional spelt using thermal, rheological, and SEC analyses, along with Concanavalin A method. Organic and conventional spelt was planted in six replicated plots, and the extracted starch was analyzed for their gelatinization properties. DSC showed that the gelatinization temperature ranged from 56.7 to 68.8 °C with an average peak of 62.4 °C, with no evidence for statistical difference in gelatinization properties between treatments. Rheological behavior variation among samples was more pronounced than that between the two growing conditions. The amylose content ranged from 23.0% to 29.8%. There was no significant difference in the molecular weight of amylose and amylopectin irrespective of the plot locations, although a significant difference was found between the amylopectin molecular weight of organic and conventional spelt starches when analyzed collectively. The organic spelt starch studied may substitute the conventional starch when gelatinization behavior is considered. 相似文献
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