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31.
The contribution of improvements in morphophysiological traits to increased gram yield in spring wheat (Triticum aestivum L.) and the achievements of breeding for high bread-making quality in Finland since the 1930s were assessed. Ten wheat cultivars released in Finland between 1939 and 1990 were evaluated in Held experiments at the Viikki Experimental Farm, University of Helsinki, Finland (60°13′N) in 1991 and 1992. Twenty-two traits representing maturity, plant architecture, plant stand structure and N accumulation, and nine quality traits, including protein concentration and protein quality, were assessed. A 20 % increase in grain yield arising from cultivar improvement was associated with a 7 % reduction in height, an 80 % improvement in lodging resistance, and a 15 % higher harvest index (HI). Ear weight was 30 % higher in the modern cultivars. The higher ear weight of the modern cultivars was a result of more grains per ear and a higher spikelet weight. No decrease in vegetative phytomass in modern cultivars was recorded in this study. Grain yield and total N accumulation increased simultaneously and a positive correlation between year of cultivar release and nitrogen index was established. Although use of high N fertilizer application rates resulted in significantly improved baking quality of the flour, no trend between baking quality and year of cultivar release was recorded. The relatively low HI recorded in this study suggests that further yield increases art-likely to be achieved by selecting for higher HI.  相似文献   
32.
Snowpack quality has been systematically monitored in Finland since winter 1975/1976 by the Finnish Environment Agency. Snow samples have been taken at the 53 groundwater observation stations in nearly natural state areas, where the impacts of local emission sources have been negligible. Thus the concentrations of impurities in snow can be considered as background levels. Samples were analyzed for conductivity, pH, major ions and trace metals (Cd, Cu, Pb, Ni, Zn and Hg). The regional variation of the chemical composition of major ions in the snowpack was outlined by cluster analysis. Sampling sites were divided into six clusters by average linkage clustering method. The largest cluster — considered as the ‘mean cluster’ — was located in central and northern Finland. The lowest levels of the total amount of dissolved impurities occurred in the cluster formed by the most northern observation site exclusively. Highest rates of the acidifying components, sulphate (SO4), nitrate (NO3), ammonium (NH4) and hydrogen ions (H+), were encountered in southern Finland. Sampling locations of southern Finland were divided into three clusters. The acidity of snow varies among these clusters that in addition of deposition of SO4 and NO3 is considerably controlled by alkaline deposition. The results of chemical analyses of snow were converted to mean monthly depositions using the water equivalent of snow and the time of deposition. Deposition of SO4 during 1985–1993 was 32% lower compared with the period 1976–1984, which presumably results from 70% reduction of sulphur emissions in Finland since the beginning of the 1980s. The deposition level of NO3-N seemed to stay relatively stable during the whole 18 year period while the deposition of NH4-N has decreased 18%.  相似文献   
33.
34.
Rapeseed, raspberry, and pine bark are promising bioactive sources of plant phenolics selected from among ca. 100 previously screened plant materials for in vitro preclinical evaluation of health related effects. Phenolic extracts and isolated fractions of the selected materials were investigated for antioxidant, antimicrobial, antiinflammatory, and antimutagenic properties as well as for cell permeability. It was shown that rapeseed and pine bark phenolics and raspberry anthocyanins were good or excellent antioxidants toward oxidation of phosphatidylcholine membrane (liposomes), rapeseed oil (crude) phenolics were effective radical scavengers (DPPH test), and both raspberry and pine bark phenolics inhibited LDL oxidation. Rapeseed oil phenolics, principally vinylsyringol, raspberry anthocyanins, and pinoresinol and matairesinol, the principal components of pine bark phenolic isolate, were effective against formation of the proinflammatory mediator, prostaglandin E(2). Raspberry ellagitannins inhibited the growth of Proteus mirabilis and Klebsiella oxytoca. Pine bark and rapeseed had minor effects on the permeability of model drugs in Caco-2 experiments. None of the tested extracts were mutagenic nor toxic to Caco-2 cells or macrophages. Thus, phenolic isolates from rapeseed, raspberry, and pine bark and are safe and bioactive for possible food applications including functional foods intended for health benefit.  相似文献   
35.
Vitamin C, tocopherols, and tocotrienols in berries of wild and cultivated sea buckthorn (Hippopha? rhamnoides L.) of different origins and harvesting dates were determined with HPLC. Wild berries of subsp. sinensis, native to China, contained 5-10 times more vitamin C in the juice fraction than the berries of subsp. rhamnoides from Europe and subsp. mongolica from Russia (4-13 vs 0.02-2 g/L juice). Genetic background and berry-harvesting date were two primary factors determining the vitamin C content in the berries. Crossing different subspecies influenced the vitamin C content to some extent. For bushes cultivated in southwest Finland, the best berry-harvesting date for high vitamin C content was the end of August. The seeds of subsp. sinensis contained less tocopherols and tocotrienols (average 130 mg/kg) compared with seeds of subsp. rhamnoides (average 290 mg/kg) and mongolica (average 250 mg/kg). The fruit flesh of sinensis berries had contents of tocopherols and tocotrienols 2-3 times higher than those found in the other two subspecies (120 mg/kg vs 40 mg/kg in rhamnoides and 50 mg/kg in mongolica). The fresh whole berries of subsp. sinensis were clearly the best source of total tocopherols and tocotrienols. The total content of tocopherols and tocotrienols in the soft parts of the berries reached the maximum level around early- to mid-September, whereas the content in seeds continued to increase until the end of November. The excellent combination of the highest content of vitamin C and tocopherols and tocotrienols makes the berries of subsp. sinensis an optimal raw material for nutritional investigation as a candidate for functional foods with special antioxidative properties.  相似文献   
36.
Abstract

Experiments were conducted with malting barley (Hordeum vulgare L.) cultivars in 2003 and 2004 in central, western and southern Lithuania to test phosphorus (P) availability at early seedling growth stage with P seed coating. Phosphorus seed coating resulted in alteration to plant stand structure traits. Despite the fact that seedling emergence sometimes decreased, the number of total and productive stems, number of grains per ear and 1000-grain weight increased. The positive effect of P seed coating on grain yield was revealed when the growth conditions during post-anthesis were favourable for exploiting the potential that was obtained during the pre-anthesis phase. In our experiment favourable conditions were considered those that generated a grain yield over 6 t ha?1. According to path coefficients analyses the significant positive effect of P seed coating on malting barley yield increase was related to seed weight increase. Although P seed coating slightly increased single grain N concentration and thus grain protein concentration, grain protein concentration ranged from 8.6% to 10.2% and met the quality standard requirements for malting barley in all trials and treatments.  相似文献   
37.
Phenolic compounds in black currants of three Finnish cultivars and their response to growth latitude and weather conditions were analyzed over a six-year period. 'Melalahti' had lower contents of total phenolic compounds (31.4% and 29.2% lower than 'Mortti' and 'Ola', respectively), total anthocyanins (32.6% and 30.5%), and total hydroxycinnamic acid derivatives (23.1% and 23.8%) (p < 0.05) and was less affected by growth latitude and weather conditions than 'Mortti' and 'Ola'. However, all the cultivars grown at higher latitude (66°34' N) had lower contents of total flavonols, total anthocyanins, and total phenolic compounds than those grown at lower latitude (60°23' N) (p < 0.05). The content of total hydroxycinnamic acid conjugates did not vary in 'Melalahti' (p > 0.05) but increased as the latitude increased in 'Mortti' and 'Ola' (p < 0.05). Temperature and radiation were the major weather variables influencing the composition of phenolic compounds. Delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, and myricetin-3-O-glucoside content showed positive correlations with temperature and radiation in all three cultivars. The study gives important guidelines for the selection of raw materials and growth sites as well as for the berry cultivation for commercial exploitation of black currant berries.  相似文献   
38.
Plants can mediate interactions between aboveground herbivores and belowground decomposers as both groups depend on plant-provided organic carbon. Most vascular plants also form symbiosis with arbuscular mycorrhizal fungi (AMF), which compete for plant carbon too. Our aim was to reveal how defoliation (trimming of plant leaves twice to 6 cm above the soil surface) and mycorrhizal infection (inoculation of the fungus Glomus claroideum BEG31), in nutrient poor and fertilized conditions, affect plant growth and resource allocation. We also tested how these effects can influence the abundance of microbial-feeding animals and nitrogen availability in the soil. We established a 12-wk microcosm study of Plantago lanceolata plants growing in autoclaved soil, into which we constructed a simplified microfood-web including saprotrophic bacteria and fungi and their nematode feeders. We found that fertilization, defoliation and inoculation of the mycorrhizal fungus all decreased P. lanceolata root growth and that fertilization increased leaf production. Plant inflorescence growth was decreased by defoliation and increased by fertilization and AMF inoculation. These results suggest a negative influence of the treatments on P. lanceolata belowground biomass allocation. Of the soil organisms, AMF root colonization decreased with fertilization and increased with defoliation. Fertilization decreased numbers of bacterial-feeding nematodes, probably because fertilized plants produced less root mass. On the other hand, bacterial feeders were more abundant when associated with defoliated than non-defoliated plants despite defoliated plants having less root mass. The AMF inoculation per se increased the abundance of fungal feeders, but the reduced and increased root AM colonization rates of fertilized and defoliated plants, respectively, were not reflected in the numbers of fungal feeders. We found no evidence of plant-mediated effects of the AM fungus on bacterial feeders, and against our prediction, soil inorganic nitrogen concentrations were not positively associated with the concomitant abundances of microbial-feeding animals. Altogether, our results suggest that (1) while defoliation, fertilization and AMF inoculation all affect plant resource allocation, (2) they do not greatly interact with each other. Moreover, it appears that (3) while changes in plant resource allocation due to fertilization and defoliation can influence numbers of bacterial feeders in the soil, (4) these effects may not significantly alter mineral N concentrations in the soil.  相似文献   
39.
A fast, one-step gas chromatographic method was developed to analyze trimethylsilyl (TMS) derivatives of sugars, fruit acids, and ascorbic acid in sea buckthorn (Hippoha? rhamnoides L.) berries. The method was applied to berry press juice of sea buckthorn of different origins grown in Finland during the 2003 and 2004 seasons. The method gave reliable results for D-fructose, D-glucose, ethyl-D-glucose, and malic, quinic, and ascorbic acids, which are the major sugars and acids in sea buckthorn juice. For the first time in sea buckthorn and evidently in any berry, the presence of ethyl beta-D-glucopyranoside is reported. The structure of ethyl glucose was verified by high-performance liquid chromatography (HPLC), gas chromatography (GC), MS, and NMR analyses of both the isolated and the synthesized compounds. In the GC method, vitamin C was analyzed as ascorbic acid only, and dehydroascorbic acid was thus not taken into account.  相似文献   
40.
Voles inflict damage to silviculture by debarking or severing tree seedlings. The large-scale impacts of vole damage to silviculture, both in terms of severity and financial losses are, however, poorly known. In autumn 2005, cyclically fluctuating vole populations were at their highest in Finland for over 15 years, which led to extensive damage to silviculture during the winter 2005/06. We carried out a nationwide assessment of the incidence, spatial extent and economic value of damage and its relation to vole abundance in privately owned forests during this winter. Damage data were obtained with a questionnaire addressed to the directors of all Forest Management Associations (FMAs) operating in Finland, and vole abundance data from 15 long-term monitoring projects across the country. Voles were confirmed to have destroyed ca. 4.7 million tree seedlings, covering a total effective damage area of ca. 2600 ha. The directors of the FMAs estimated that the actual level of damage was likely to exceed 8.5 million seedlings, or 5400 ha. Roughly 80% of all damage was inflicted on Norway spruce (Picea abies), ca. 10% on Scots pine (Pinus sylvestris) and ca. 10% on birch (Betula sp.) and other species. Considering costs of replanting alone, a most likely very conservative estimate of the financial impact of vole damage during the winter 2005/06 lies between 2.2 and 4.0 million €. The occurrence of damage during the winter was positively related to vole abundance in the previous autumn. This validates vole population monitoring as an effective tool for forecasting near-future damage to silviculture. Our results suggest that if vole populations continue to fluctuate as they currently do, levels of damage to Finnish forests will be great also in the future, far exceeding damage levels recorded in earlier decades.  相似文献   
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