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51.
The goal of this study was to evaluate the effect of organic (OS) and conventional (CS) farming of Arabica coffee on chemical and microbiological soil properties and to identify which attributes correlate and/or contribute to distinguishing these two management systems. We collected soil samples on a 100 × 100 m2 grid in both, the OS and CS, in winter and summer and submitted chemical and microbiological properties to univariate and multivariate analyses (canonical discriminant analysis – CDA – and redundancy analysis – RDA). The best indicators to discriminate OS and CS were chemical and microbiological properties, as the elements calcium (Ca) and boron (B), besides microbial biomass carbon (MBC), metabolic quotient (qCO2), acid phosphatase (ACP), and alkaline phosphatase (ALP). The RDA showed that, regardless of the season, MBC and ACP correlated with nitrogen (N), sulfur (S) and organic matter (OM), whereas basal respiration (C-CO2) and ACP correlated with qCO2 and with magnesium (Mg), calcium (Ca), phosphorus (P), potassium (K) and pH.  相似文献   
52.
当我们把中国人自己的第一粒樱桃样的咖啡红果采摘下来,第一次烘焙、第一次研磨、第一次冲调、第一杯热咖啡飘散出醇香的时候,有关中国咖啡种植业和新中国咖啡产业60年的崛起历程就永久载人史册,成为一段动人的历史佳话。本文总结中国咖啡产业60年的崛起所经历的4个历史时期。农业科研院所对中国咖啡的助推以及对外开放和国外企业挺进对中国咖啡产业的促进作用。  相似文献   
53.
咖啡在研磨过程中易挥发性风味物质大量散失,为探索不易挥发性物质在研磨过程中的变化,将焙炒好的咖啡豆用植物粉碎机粉碎,然后用臼式研磨机按不同时间进行研磨,用正己烷做溶剂进行萃取后,用GC/MS进行图谱扫描,分析咖啡在研磨过程中不易挥发性风味物质的变化。研究结果表明,咖啡在研磨过程中不易挥发性风味物质散失严重,到第9分钟时散失率达13.1%,25min时风味物质散失率达到26.4%。各风味物质的散失活性不同,且对热的反应也不同。  相似文献   
54.
我国咖啡产业发展现状及前景   总被引:2,自引:0,他引:2  
简述在世界咖啡生产、消费及市场价格走向背景下,中国咖啡产业现状及发展前景。  相似文献   
55.
In this study, we used image‐processing techniques to examine the spatial pattern of land‐use and land‐cover (LULC) change that occurred in the coffee growing area in the Western Ghats of India during the international coffee crisis in the 1990s. The study also ascertains the driving forces of these changes using qualitative research methods that include archival studies and interviews of knowledgeable individuals. We analyzed Landsat Thematic Mapper (TM) for 1991 and Landsat ETM+ for 2002 to quantify LULC. Historical land‐use changes in different land ownership regimes were also analyzed. Global coffee market fluctuations were found to be the major cause of landscape change in the study region. When the global coffee prices increased, more forested areas were cleared for coffee cultivation. Failure of global coffee market forced farmers to convert land from subsistence farming (rice) to short‐period commercial crops like ginger. This also resulted in land degradation in rice paddies. For the farmers in the Western Ghats, LULC decisions are one of the methods used to cope with the vulnerability created due to the international coffee crisis. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
56.
Bioassay-guided partition of the extract of the Red Sea sponge Pseudoceratina arabica and HPLC purification of the active fraction gave a psammaplysin dimer, psammaceratin A (1), along with psammaplysin A (2). The dimer comprises two units of psammaplysin A (2) connected via the terminal amines with an unprecedented (2Z,3Z)-2,3-bis(aminomethylene)succinamide moiety, and it represents the first dimer to be identified among the psammaplysin family. Data from 1D- and 2D-NMR and HRMS supported the chemical structures of the compounds. Psammaceratin A (1) and psammaplysin A (2) exhibited significant growth inhibition of HCT 116, HeLa, and MBA-MB-231 cells down to 3.1 μM.  相似文献   
57.
58.
Abstract

An investigation was conducted to compare differences in chemical characteristics of Costa Rica soils under continuous cultivation and under forest vegetation. Inceptisols from young volcanic material under forest, sugar cane, coffee and pasture, respectively, were sampled in the San Carlos region of Costa Rica, and analysed for pH, organic matter, N, Ca, Mg, K, Na, Al, Fe, Zn and Mn contents. Indications were obtained that continuous cropping for 1 to 22 years with sugar cane resulted in a decrease in Ca and Mg content and an increase in acid extractable Al concentrations, compared to amounts found in forest soils. In soils under coffee the only significant changes were a reduction in soil organic matter, N and Al contents. Exchangeable bases decreased slightly during the first two years, but in fields 15 years under coffee, the content of exchangeable bases was affected slightly, except for a relatively marked decrease in amounts of Mg. Conversion into pasture maintained soil fertility at a level comparable to that found in the forest soil ecosystem. It was concluded that differences in vegetational ecosystems caused soil chemical changes, but deforestation in the tropics did not necessarily result in rapid soil degradation processes. The magnitude of the data showed that the soil in the San Carlos region of Costa Rica had been cultivated for at least 10 to 20 years without producing evidence of excessive deterioration.  相似文献   
59.
土壤干旱对小粒种咖啡有关生理参数的影响   总被引:1,自引:0,他引:1  
对塑料袋一年生咖啡苗定期停止淋水,使土壤遭受不断加剧的干旱胁迫,以检测水分供应对咖啡生理状况的影响。试验结果表明:轻度水分胁迫,如1d不淋水,即导致咖啡光合速率、蒸腾速率、可溶性蛋白质和叶绿素、类胡萝卜素含量以及含水量、气孔开张率、水势等生理参数开始下降;而过氧化物酶活性、脯氨酸和丙二醛含量以及细胞透性等生理参数开始上升,且随土壤水分胁迫的逐步加剧,上述各生理参数呈渐进性恶变。光合速率对土壤水分的反应属敏感参数之一,轻度干旱即使光合速率明显下降。高温间歇干旱期,常规管理的田间含水量能使咖啡光合速率受到抑制,灌水可促使光合速率提高。  相似文献   
60.
Nutritional and physiological significance of micronutrients in coffee plants, especially with regard to nickel (Ni) is still unknown. The dynamics of nitrogen (N), phosphorus (P), potassium (K) and Ni accumulation in coffee fruits, as well as their relationships with total soluble protein, amino acids, reducing sugars, and starch content during coffee fruit development (green, ripe, and dry fruits), were investigated. Coffee trees received three N fertilizer rates (0, 150, and 300 kg of N ha?1) as ammonium sulfate split into three applications per year. Nitrogen fertilization increased reducing sugars and starch concentrations in ripe fruits. In contrast, green fruits showed the highest amino acid and Ni concentrations. Fruit Ni concentration decreased in both green and ripe fruits as N rates increased; thus, indicating the possibility of either a N-associated dilution effect on Ni concentration or that Ni uptake by roots and/or transport to developing fruit was limiting. Plant nutritional status and fruit development stage influenced the coffee grain chemical composition. Furthermore, the variation in reducing sugars and starch content was more closely linked to the stage of fruit development than to N supply. A supposed relationship among the decreased of caffeine, starch, amino acids, and proteins with Ni content during green fruit development suggests a fundamental role for Ni in coffee fruit ripening. The interaction between N and Ni metabolism during fruit ripening might influence the chemical parameters involved in the coffee grain quality. This is the first report documenting changes in Ni concentrations of coffee fruit as a function of N fertilization rates and the development stage, but further research is needed to better understand the significance of N-Ni interaction in developing coffee fruit.  相似文献   
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