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《Scientia Horticulturae》2001,87(1-2):93-105
Campanula carpatica Jacq. ‘Blue Clips’ plants were grown in a greenhouse under nine combinations of day and night temperatures created by moving plants every 12 h among three day/night temperatures (15, 20, and 25°C). At each temperature, there were three daily light integrals (DLI; 4.2, 10.8, and 15.8 mol m−2 per day, averaged over the experimental period) created with varying supplemental light, and ambient (≈400 μmol mol−1) and enriched (≈600 μmol mol−1) CO2 concentrations. Time to flower was closely related to average daily temperature (ADT), and was not significantly affected by the day or night temperatures delivered to achieve a specific ADT. Time to flower was not largely affected by DLI or CO2 enrichment. As plant ADT increased between 15 and 25°C, flower diameter decreased about 1 mm per degree and was not related to the difference between day and night temperatures (DIF). Flower diameter was smallest and least sensitive to changes in temperature at lower DLI and at ambient CO2 levels. There were 10 less flower buds and 0.3 g less dry mass per plant at first flower for every 1° increase in plant ADT at high and medium DLIs. Flower bud number and dry mass were relatively low and less sensitive to changes in ADT at low DLI, and increased slightly with CO2 enrichment at medium and high but not at low DLI. Plant height was not related to ADT, but increased linearly as DIF increased from −6 to 12°C at all DLIs, but the response was stronger under low DLI than high and medium DLIs. Flower bud number and dry mass were correlated closely with the ratio of DLI to daily thermal time (base temperature of 0°C). Flower bud number and dry mass were highest when C. carpatica plants were grown at 15°C with a DLI of 10–15 mol m−2 per day.  相似文献   

3.
AIM: To observe the effects of diosmin on the production of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), IL-6, IL-8 and IL-10 in serum and kidney tissues of rats with kidney ischemia and reperfusion (I/R). METHODS: Sprague-Dawley rats (180 in total) were randomly divided into 3 groups including sham operation group (sham),I/R group and diosmin+I/R group (diosmin+I/R). At the end of the experiment, the blood and kidney tissues were obtained and TNF-α, IL-1β, IL-6, IL-8 and IL-10 were detected by ELISA. RESULTS: The levels of TNF-α, IL-1β, IL-6, IL-8 and IL-10 in serum and kidney tissues in I/R group and diosmin+I/R group were significantly higher than those in sham group (P<0.01 or P<0.05). Following the development of the pathologic process, the level of TNF-α, IL-1β, IL-6 and IL-8 was significantly increased in I/R group and diosmin+I/R groups, but the level of IL-10 was significantly decreased in I/R group and significantly increased in diosmin+I/R group. The levels of TNF-α, IL-1β, IL-6 and IL-8 in I/R group was significantly higher than those in diosmin+I/R group (except TNF-α at 1 h in diosmin+I/R group). The level of IL-10 in diosmin+I/R group was significantly higher than that in I/R group (P<0.01 or P<0.05). CONCLUSION: Diosmin not only decreases the production of TNF-α, IL-1β, IL-6 and IL-8, but also promotes the production of anti-inflammatory cytokine IL-10, suggesting that the protective effect of diosmin on kidney I/R injury was associated with anti-inflammatory mechanism.  相似文献   

4.
Yuri  José A.  Neira  Amalia  Fuentes  Mauricio  Sáez  Bárbara  Razmilic  Iván 《Erwerbs-Obstbau》2022,64(2):201-209

Total and specific phenolic compounds and antioxidant capacity were quantified over two seasons in flowers, leaves, fruitlets, and ripe fruit at harvest of the apple cultivars ‘Brookfield’, ‘Granny Smith’ and ‘Fuji’, as well the crabapple cultivars ‘Hillary’ and ‘Manchurian’. The results showed that leaves had the highest phenol concentrations and antioxidant capacity. Phenolic and antioxidant content was progressively lower from flowers, fruitlets, and ripe harvested fruit. There were high concentrations of phloridzin in flowers and leaves, while concentrations were lower in fruitlets, peel, and entire fruit at harvest. The phenolic compound with the highest concentration in peel was quercetin glycoside, while in the entire fruit it was flavanols. The studied crabapple cultivars did not present differences between them in phenolic compounds and antioxidant capacity.

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5.
Most landscape definitions in the western world are based on soil, climatic, or physiographic features and do not integrate humans as an integral part of the landscape. We present an approach where landscape types have been delineated in southern Québec, Canada based on current land use where anthropogenic and agricultural activities are concentrated as a practical application of the holistic approach in landscape definition. Landsat-TM satellite images were classified and the 27 habitat classes were regrouped into 5 general land cover classes (cash crop, dairy farming, forest, anthropogenic, wetlands) and overlaid onto soil landscape polygons to characterize natural boundary units. Cluster analyses were used to aggregate these polygons into seven agricultural types of land scape forming a gradient from urban and high-intensity cash crop farming activities to landscapes dominated by a mosaic of agriculture and forested areas. Multivariate analyses of raw data and of socio-economic and farming practices variables were used to describe the defined types of landscape and these were projected over three established land classification systems of southern Québec (Canadian ecoregions, North American Bird Conservation Initiative regions and Corn Heat Unit regions) to compare their similarity in terms of land cover and for planning of future ecological studies. Because agricultural landscapes are highly dynamic, they are bound to undergo changes in the near future. Our landscape delineation may serve as an experimental setup where land scape dynamics and wildlife populations and community structures could be monitored. Because the information we used to delineate and characterize agricultural landscape types is readily available in other countries, our approach could easily be adapted to similar data sources under and a wide variety of landscape types. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

6.
In this study, the interaction between crop load and irrigation level on yield, fruit size, skin color and stem-end splitting fruit ratio in the apple cultivar ‘Gala, Galaxy’ grafted on rootstock M9 were investigated. Six irrigation programs were applied during the whole growth season: deficit irrigation (rates of 0.25 kc, 0.50 kc, 0.75 kc), full irrigation (rate of 1.00 kc), excess irrigation (rate of 1.25 kc) and non-irrigation (rates of 0.00 kc of “Class A” pan evaporation coefficient). Four crop loads in each irrigation application were performed by hand thinning after the June drop as a- a low crop load (3 fruits cm?2 TCA), b- a medium crop load (5 fruits cm?2 TCA), c- a heavy crop load (7 fruits cm?2 TCA), and d- an un-thinned crop load (>?7 fruits cm?2 TCA). The total tree yield increased with crop load and irrigation levels. Fruit size was significantly increased by the low crop load. Irrigation increased the fruit size compared to non-irrigation treatment. Further 0.75 kc, 1.00 kc and 1.25 kc irrigation treatments significantly increased the fruit length. Irrigation reduced the fruit flesh firmness. While the low crop load increased the skin red color, it decreased the fruit skin brightness. The yellowness of skin decreased with increasing in the irrigation amount. Irrigation reduced the skin brightness and yellowness, but it increased red color. Crop load and irrigation significantly affected the stem-end splitting fruit ratio. While the splitting fruit ratio increased with a decrease in the crop load, it decreased with an increase in irrigation amount, relatively. Consequently, the low and medium crop load treatments would be beneficial to increase the ratio of marketable fruits without any significant losses in yield for ‘Gala’ apple, especially under 0.75 kc deficit irrigation treatment.  相似文献   

7.
Landscape Ecology - Connections among ecosystems and their components are critical to maintaining ecological functions and benefits in human-modified landscapes, including urban areas. However, the...  相似文献   

8.
A flavor-related enzyme from Toona sinensis (TS), ?-glutamyl-transpeptidase (GGT), was purified 40.67-fold with 13.40% recovery using ammonium sulfate precipitation, dialysis and gel filtration chromatography. Gel filtration chromatography and sodium dodecyl sulfate acryl amide gel electrophoresis (SDS-PAGE) revealed that GGT was a heterodimer with a molecular weight of 90 kDa, and the molecular size of its two subunits was 26 kDa and 64 kDa, respectively. The apparent Km and Vmax of GGT were 3.623 μmol/mL and 2.831 μmol/mL/min of protein, respectively. The optimum reaction temperature was 60°C, while the optimum pH was 7.0. GGT can tolerate temperatures of 70°C for a short time and can keep stable activity at 60°C for more than 2 hours. The effect of metal ions on GGT activity showed that Cu2+ and Zn2+ had strong inhibition, while Fe3+ had strong activation, and other metal ions had only a slight effect. LC-MS analysis indicated that GGT catalyzed (S, S)-γ-glutamyl-(cis-S-1-propenyl)-thioglycine, a flavor precursor found in TS, to release glutamic acid moiety.  相似文献   

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In a harsh (Kunia) and an ideal (Kona) growing region of Hawai‘i, sun grown Coffea arabica L. was compared to coffee shaded with varying degrees of black and aluminized shade cloth, macadamia trees, and a novel, spray-on shade composed mostly of kaolin. Shading did not appreciably affect organoleptic quality. Shading resulted in statistically different yields in the macadamia (16% of sun) and kaolin (199% of sun) treatments in the second year compared to full sun treatments in their respective locations, although a negative, linear trend was observed with increased shading. The lack of significant differences in yields between the shade cloth and sun treatments was likely a result of large yield variation among replicates. Bean sizes differed little between shade treatments and the percentage of defects and broken beans were generally not significantly different among the treatments in Kunia. Kona bean sizes and characteristics were not different. Shading reduced surface leaf temperatures and increased specific leaf area but generally did not affect lateral nodal growth. Leaf nutrient concentration differed between treatments.  相似文献   

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The Norwegain mountains have had a central role in the subsistence agroecosystems by providing vast biological resources for humans and their livestock since 4000–3500 BP as indicated by paleoecological records. Later with the development of the summer farming system the use of the mountains was intensified. This long-term use of the mountains has shaped a montane cultural landscape by livestock grazing, mowing for hay, fuel collection and a variety of other uses. The result is a significant increase of the grassland areas at the expense of the forest. Those semi-natural grasslands and heathlands with specific biological diversity have until recently dominated the mountains but are today decreasing due to forest invasion – which in turn is a result of changes in human land use. The present paper focuses on changes in landscape pattern and differences in landscape development in two mountain valleys with summer farming activities, in Mid-Norway, over the period 1960s–1990s, and seeks to interpret the changes in relation to differential land use and environmental factors. This study contributes examples from human shaped ecosystems in mountains where the fragmentation of semi-natural habitats is addressed. A set of landscape pattern indices commonly used in landscape ecological studies is also used here, and their ecological relevance in the present context is dealt with. The implications of changed land use for biodiversity conservation in those mountains and the relationships to future sustainable agriculture is also briefly discussed.  相似文献   

13.
Summary

The effects of light, moderate, or heavy thinning (5, 10, or 20 cm between fruit, respectively), conducted before (7 d or 15 d), during, or after (7 d or 15 d) pit hardening (PH), on the incidence of split pits, fruit yield, fruit quality characteristics, and leaf mineral contents, were studied in the canning peach (Prunus persica L. Batsch.) cultivar ‘Andross’ over two growing seasons. The percentage of fruit with split pits increased by 58.2% in heavily-thinned trees compared with moderately- or lightly-thinned trees, and by 22.9% for the earliest time of thinning (15 d before PH) compared with thinning during, or after PH. Fruit fresh weight (FW) was greater in moderately- and heavily-thinned trees compared with lightly-thinned trees, but yields were similar among the different crop-load treatments. The latest time of thinning (15 d after PH) also had a negative impact on yield at first harvest and on total yield, fruit FW, and delayed fruit ripening compared to thinning during, and 15 d before PH. Total anti-oxidant capacities and phenolic contents were usually greater in fruit from heavily-thinned compared with lightly- or moderately-thinned trees only when thinning was conducted during, or 15 d after PH. Moreover, anti-oxidant levels were highest in fruit from the earliest-thinned trees. There was no significant effect of crop load, or of time of thinning application treatment on fruit colour, or on the K, P, Fe, Mn, and Cu contents of leaf tissues. In conclusion, light or moderate thinning during PH resulted in minimal split pits during processing, and in optimal yields and fruit quality characteristics in the canning peach cultivar ‘Andross’.  相似文献   

14.
Cultural services provided by green space networks and in particular leisure and recreational opportunities are central to the quality of life of those living in urban areas. However, the literature concerned with green space networks has mainly focused on planning aspects rather than on recreational use. The aim of this study was to evaluate the recreational use of, and concerns about, a naturalistic green space network. The case study location was the naturalistic woodland framework in Birchwood, Warrington, UK, known as Birchwood Forest Park. Non-participant observation and content analysis of local archives were used to collect quantitative and qualitative data. Birchwood Forest Park was used more for leisure activities (52.8%, N=1825; i.e. recreation, sports or play) than for utilitarian purposes (47.2%, N=1825; i.e. as walking or cycling thoroughfare). However, utilitarian walking (30%, N=1825) was the most frequent type of activity observed. The maintenance of the naturalistic woodland framework was the most frequent concern mentioned in the local archives (33.3%, N=234). This case study suggests that the recreational patterns in, as well as peoples' concerns about, naturalistic urban landscapes may be a factor of high-quality maintenance and associated local aesthetic and cultural perceptions. In developing, planning or managing comprehensive urban green space networks it is important to ensure that natural looking scenes are well maintained and that the local community is culturally connected to such scenes.  相似文献   

15.
Urban environments are often characterized by extensive paved surfaces, exacerbating the urban heat island effect. At the same time, limited root space due to underground infrastructure poses a challenge for planting new trees in these areas. Trees in planters have emerged as popular design elements, offering innovative and sustainable greening solutions, particularly in urban environments with limited rooting space. However, growing conditions in planters may strongly impact tree growth and the provision of environmental ecosystem services (ES). In this 3-year study, we analyzed tree growth and ecosystem services (cooling by shading, CO2-fixation) of London plane (Platanus x hispanica Münchh.) and small-leaved lime (Tilia cordata Mill.) in four planting treatments: in-ground (G), planters in the ground (PG), non-insulated plastic planters (P), and insulated planters (PI). We also recorded soil temperature throughout the experiment and implemented soil drought conditions by reducing soil irrigation for half of the trees after one year. Our findings revealed higher thermal fluctuations in soil temperature within non-insulated plastic planters (P), reaching a maximum of 45 °C, surpassing the critical temperature threshold for plant growth (>38 °C). In contrast, insulated planters (PI) effectively mitigated soil temperatures, staying below 33.8 °C. When planted in the ground (G), P. x hispanica exhibited a significantly higher stem diameter increment (52–66%) compared to other planting treatments, aligning with the provision of ecosystem services. However, T. cordata trees showed a more moderate response to planting treatments in terms of growth and ecosystem service provision. Furthermore, the implementation of soil drought conditions resulted in a reduction of up to 34% in stem diameter increment for P. x hispanica and up to 25% for T. cordata. Our results underscore the necessity of tree species-specific knowledge about growth responses to different planting treatments for effective urban planning perspectives, as the provision of ecosystem services may be influenced differently.  相似文献   

16.
Summary

Changes of carbohydrate concentrations in different parts of the flower and the surrounding tissues (leaves, spurs and shoots) were measured in apple (Malus pumila) in 1987 and 1988, during the periods of flowering and fruit setting, to investigate their importance for fruit setting. HPLC was used for soluble sugar and sorbitol analysis. Starch was hydrolysed to glucose enzymatically and glucose concentration was determined colorometrically to estimate starch concentrations. Soluble sugars plus sorbitol (the soluble pool) increased rapidly in all parts of the flower from bud burst until full bloom. In contrast, in the same period, starch concentrations decreased rapidly and reached about zero at full bloom in the storage organs (shoots and spurs), indicating starch conversion to sugars and their movement to the growing flowers. Sorbitol was the most abundant carbohydrate in all apple tissue measured, with the exception of sepals, in which glucose concentration was the highest from full bloom onwards. Sepals had much higher glucose and fructose concentrations than leaf laminae but much lower sorbitol concentrations. Although dry weight, soluble pool and starch concentrations and total soluble pool content increased in the receptacle after petal fall, sucrose concentrations and total sucrose content dramatically decreased. These results suggest a preferential mobilization and utilization of sucrose rather than sorbitol during the fruit setting period and probably an important role of sucrose metabolism in fruit setting.  相似文献   

17.
School grounds can have multiple values, and especially sufficient size, green elements, variation, integrated design and participatory development have been described as positive qualities. However, many studies have focused on pre-school and primary school grounds, while less is known about school grounds for adolescents. This study explored how secondary school students experience and use school grounds of varying size, content and design. The study included one class in year 8 (aged 14–15) at each of three schools in southern Sweden. A questionnaire with mainly open questions was distributed, followed by both individual interviews and walking interviews with four students from each class. The results show that school grounds were appreciated, but also that many chose to stay indoors. Large surface area and varied content, with ball courts, greenery, seating and multifunctional equipment, were valued, but a school ground design with integrated and pleasant settings, allowing socialising and activities, particularly support use by secondary school students.  相似文献   

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In high-income countries depression and cardiovascular diseases were predicted to be the two leading causes of DALYs in the year 2030. Private-life stress fosters both kinds of diseases. Scientific findings already show that forest exposure has stress-reducing effects. Particularly in Japan, people have practiced forest bathing to improve their health. The German population also has a strong connection to its forests, and forest law allows forest access, regardless of ownership structure. Hence, the question arises of whether forest exposure could be used in Germany as a kind of stress-coping strategy. To a certain degree, the success of such a strategy in Germany would require the participation of the stakeholders that are active in both the health and the forestry sectors. Therefore, it seems necessary to gain insight into German forest and health professionals' understanding and attitude concerning forest-related health benefits. For this reason, in this pilot study, guideline interviews with professionals of both sectors and with professionals standing in between these professions were conducted, recorded and transcribed. On the one hand, each professional’s presumptions regarding the health-fostering effects of forests were investigated, derived from their subjective certainty that forest exposure has health-fostering effects. In addition, a thought experiment was used to estimate the level of willingness to cooperate with each other in order to motivate people to be physically active in forests. For analysis, Mayring’s qualitative content analysis and a frequency analysis (MaxQDA) were applied. Findings show that most of the interviewed professionals presume forests to have health-fostering effects. Furthermore, something derived from the statements within the context of the thought experiment was that most professionals seem to be willing to cooperate with the other sector. Hence, it might be conceivable that forest exposure may be part of a German stress-coping strategy.  相似文献   

20.
Summary

Dry-matter accumulation patterns and anatomical aspects of development and abscission of inflorescence buds borne on shoots of fruiting (BF) and non-fruiting (BNF) branches of bearing trees and in non-bearing branches of disbudded (NBD) pistillate trees of pistachio (Pistacia vera L.) were studied from the end of May to mid September. In NBD trees, inflorescence-bud summer drop was negligible and, by the end of the growing season, dry-matter content in NBD buds was three times higher than in BF buds. The anatomical investigation showed that the inflorescence buds, irrespective of their being on shoots of fruiting or not-fruiting branches, undergo the same differentiation process, which is completed by the end of spring. In June and July, signs of degenerations are detectable in the conducting tissue of the buds that will abscise. The degeneration seems to precede and, presumably, trigger the onset of abscission layers, which may develop in different points of the inflorescence. It is suggested that the event triggering the onset of the abscission process precedes the phase of rapid embryo development and that it might be ascribed to the embryo in the phase following the first zygotic division.  相似文献   

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