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711.
短枝富士品种是富士苹果中一个非常重要的芽变类型,具有易成花、结果早等突出特点,本试验研究了套袋条件下“烟富6号”“烟富7号”2个短枝富士苹果果实品质、糖酸组分和香气物质的差异。结果表明,2个品种均为酯香型品种,“烟富7号”品种果实的平均单果质量、果形指数、果实硬度、琥珀酸、草酸、柠檬酸以及蔗糖和山梨醇含量均高于“烟富6号”;2个品种的主要香气成分存在差异,“烟富6号”主要香气成分为乙酸己酯和2-甲基丁酸己酯,“烟富7号”主要香气成分为2-甲基丁酸己酯和丙酸己酯;套袋果实摘袋后,“烟富6号”先条纹状着色再变为片红,而“烟富7号”为片状着色。 相似文献
712.
Somaclonal variation for plant height, plant spread, leaf shape, leaf size, leaf form, herb yield, essential oil content and 10 important constituents of the essential oil was studied in an Indian cultivar, ‘Bourbon’ of rose‐scented geranium (Pelargonium graveolens). Significantly larger variance was observed among in vitro‐regenerated plants of the SC1 generation (first generation following an in vitro phase) than among parental plants raised from stem cuttings for herb yield, plant height, leaf size, essential oil content, and for the contents of cis‐rose oxide, trans‐rose oxide, isomenthone and 10‐epi‐γ‐eudesmol in the essential oil. Plants of the SC1 generation showing values beyond the higher or lower limit (depending on the trait) of the range observed among parental plants for different traits were developed into clones by their multiplication through stem cuttings, and evaluated again in the SC2 generation (second generation following the in vitro phase). Somaclones selected for plant spread, and for the contents of linalool and trans‐rose oxide in their essential oils did not breed true in the SC2 generation. However, for the remaining traits studied, 13–100% of the selected clones retained their selected traits in the SC2 generation, suggesting that the changes in these somaclones were due to genetic causes. 相似文献
713.
百花湖水库表层沉积物中PAHs生态风险评价 总被引:2,自引:0,他引:2
2010年11月20日采集贵阳市百花湖水库4个站点表层沉积物样品,参照美国EPA标准方法,采用气相色谱与质谱联用(GC/MS)技术,对表层沉积物样品中多环芳烃(PAHs)进行检测分析.结果表明,百花湖水库表层沉积物样品中16种PAHs的总含量为714.8~1 167.1 ng/g,平均值为862.95 ng/g,能检出的PAHs均以2~4环的芳香物为主,多环芳烃主要来自于化石燃料和生物质的燃烧.风险评价结果表明,严重的多环芳烃生态风险在百花湖水库沉积物中不存在,仅苊、芴和二苯并(a,h)蒽含量介于毒性效应区间低值(ERL)和毒性效应区间中值(ERM)之间,PAHs对生态环境的影响目前处于较低风险水平. 相似文献
714.
以宁波地区土壤中多环芳烃的含量调查结果为基础,采用美国能源部风险评估信息系统的暴露量化方法和美国环保局健康风险评估手册的风险表征方法,评估了土壤中16种多环芳烃对户外劳作者的健康风险。结果表明,宁波户外劳作者由于土壤中多环芳烃引起的平均非致癌危害指数为1.09×10-5,平均致癌风险值为3.17×10-7,可判定对人体健康的危害较小。宁波地区致癌多环芳烃含量最高暴露点致癌风险值为1.45×10-6,没有超过致癌风险水平上限(10-4),说明致癌风险尚在可接受范围内。多环芳烃中苯并(a)芘对综合致癌风险贡献最大,贡献率高达65.6%,应注意防范土壤中该污染物引起的健康危害。宁波户外劳作者受到的非致癌危害和致癌风险主要由直接摄入途径和皮肤接触途径贡献,两种途径对非致癌危害和致癌风险贡献率分别达到89%和100%,呼吸摄入引起的非致癌危害和致癌风险则相对较小。 相似文献
715.
The transformation profiles of polycyclic aromatic hydrocarbons (PAHs) by pure laccases from Trametes versicolor and Pycnoporus sanguineus, and the optimal reaction conditions (acetonitrile concentration, pH, temperature and incubation time) were determined. Anthracene was the most transformable PAH by both laccases, followed by benzo[a]pyrene, and benzo[a]anthracene. Laccase-mediator system (LMS) could not only improve the PAH oxidation but also extend the substrate types compared to laccase alone. 5e/0 or 10~ (v/v) of acetonitrile concentration, pH 4, temperature of 40 ~C, and incubation time of 24 h were most favorable for anthracene oxidation by laccase from T. versicolor or P. sanguineus. The gas chromatography-mass spectrometry analysis indicated that 9,10- anthraquinone was the main product of anthracene transformed by laccase from T. versicolor. Microtox test results showed that both anthracene and its laccase-transformation products were not acute toxic compounds, suggesting that laccase-treatment of anthracene would not increase the acute toxicity of contaminated site. 相似文献
716.
M. R. CRDENAS-AQUINO G. SALOMN-HERNáNDEZ . AGUILAR-CHVEZ M. L. LUNA-GUIDO R. MARSCH L. DENDOOVEN 《土壤圈》2014,24(6):783-790
Surfactants, such as non-ionic Surfynol 485 (ethoxylated 2,4,7,9-tetramethyl-5-decyne-4,7-diol), have been applied to accelerate removal of polycyclic aromatic hydrocarbons from soil. This study investigated the dissipation of anthracene, and carbon (C) and nitrogen (N) mineralization in soil amended with non-ionic Surfynol 485 at different rates. Soil samples of a Typic Fragiudept taken from Otumba, Mexico were spiked with anthracene at a final concentration of 520 mg kg^-1 dry soil using acetone as solvent, amended with 0.0, 24.9, 49.8 or 124.4 g kg^-1 soil of the surfactant and incubated in the laboratory. The soil not amended with anthracene, acetone and the surfactant was used as a control. Dynamics of C and N and the concentration of anthracene were monitored for 56 d. After 56 d of incubation, 38% of the anthracene was removed from the unamended soil, and 47%, 55% and 66% of the anthracene were removed when 24.9, 49.8 and 124.4 g kg^-1 of the surfactant were applied, respectively. Application of acetone, anthracene or surfactant increased the emission of CO2, but decreased the mineral N compared to the unamended control. Applying the surfactant to the acetone or anthracene-amended soil reduced emission of CO2, but increased the mineral N at the lower application rates of the surfactant. It was found that the application of the non-ionic surfactant increased the bioavailability of anthracene and thus its removal from soil, increased C mineralization, but decreased N miaeralization. Consequently, the application of non-ionic surfactant could be easily used to accelerate the removal of pollutants from hydrocarbon-contaminated soils, but mineral N in the soil would decrease, which might inhibit plant growth. 相似文献
717.
岭头单枞乌龙茶做青过程中芳香成分的变化研究 总被引:5,自引:0,他引:5
用气相色谱-质谱法分析了岭头单枞乌龙茶做青过程中香气组分的变化。结果表明;从萎凋叶→第1次摇青静置叶→第3次摇青静置叶→第5次摇青静置叶,芳香物质种类增多。精油总量增加,说明做青对岭头单枞乌龙茶香气形成起着重要的作用。 相似文献
718.
香料烟不同叶位和成熟度叶片的植物学特性研究 总被引:3,自引:1,他引:3
1992~1993年在河南农业大学采用盆栽方法对芳香型和吃味型香料烟不同叶位和成熟度叶片的植物学特性进行了研究。结果表明,在相同营养条件下,芳香型品种Basma的单株叶片数较吃味型品种Samsun的少。Basma品种叶片的腺毛密度、单位面积分泌细胞数、气孔密度和气孔宽长比均随叶位的升高而增大。Basma和Samsun品种叶片的干鲜比和单位叶面积重随叶位的升高而增大,不同成熟度则表现为适熟叶最高,其次为过熟和欠熟。Basma品种叶片的干鲜比和单位叶面积重分别较Samsun提高26.24%和30.10%,说明Basma品种叶片内含物充实,为该品种的浓郁芳香奠定了基础。 相似文献
719.
720.
施用锌、铁、镧肥对香稻米质和产量的影响 总被引:7,自引:0,他引:7
以杂交香稻组合培杂软香和常规香稻品种桂香占为材料,采用盆栽试验,研究了施用锌、铁、镧肥对香稻米质和产量的影响。结果表明,氯化锌基施和喷施及氯化镧基施处理均能显著地提高培杂软香和桂香占的整精米率,6个锌、铁、镧肥施用处理均能显著地增加桂香占的整精米率而降低其垩白粒率,氯化铁基施和喷施处理亦能显著地降低培杂软香的垩白度;氯化锌喷施处理能显著地提高培杂软香和桂香占的结实率和产量,氯化镧和氯化铁喷施处理亦能显著提高桂香占的产量。 相似文献