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以近期完成的云南省2008-2009年榨季甘蔗种植情况的统计结果,分析云南省2008-2009年榨季甘蔗品种、种植类型的布局以及现代甘蔗农艺技术的推广现状,揭示云南省甘蔗种植布局中存在的问题。提出了相应的建议。 相似文献
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草莓品种对蚜虫的抗性机制 总被引：1，自引：1，他引：0
为探讨草莓品种对蚜虫的抗性机理,以5个常规草莓品种为试材,通过调查、测定大棚内蚜虫自然发生动态和室内人工接虫后种群变化,并对草莓叶片的形态学和生理学特性与抗蚜性的关系进行了分析。结果表明章姬对蚜虫高感,丰香感,卡姆罗莎和吐德拉抗,弗吉尼亚高抗。草莓品种对蚜虫抗性与叶片背面的茸毛密度成正相关,与气孔密度呈显著负相关;与叶片的木质素含量成正比;与酚类物质含量无显著关系,与总游离氨基酸、可溶性固形物含量和水分含量无明显的线性关系。但草莓对蚜虫的抗性程度与叶片中脯氨酸、缬氨酸和胱氨酸的含量有关,特别是缬氨酸和胱氨酸在感蚜品种中的含量是抗蚜品种中的2～3倍。 相似文献
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Residential properties in the United States represent a considerable amount of land area and contain substantial tree cover. Homeowners are important decision makers in the management of city trees because they influence the structure of urban forests, and ultimately, ecosystem service potential. To better understand the perceptions, knowledge, and practices of homeowners regarding residential tree preservation, we surveyed owners of newer versus older homes in a midwestern suburb in the United States. We found that newer homeowners were younger, wealthier, and less knowledgeable about the natural aspects of their property. During the redevelopment process, they relied on professionals to make major decisions regarding tree preservation. In contrast, owners of older homes often identified as retirees and gardeners, had more knowledge of the natural aspects of their property, and were more likely to hire an arborist. Regardless of these differences, both homeowner groups expressed equal appreciation for nature, planted, pruned, and mulched their trees, experienced tree loss, hired landscaping and tree care professionals, and communicated with the City’s Forestry Section. The results of our study further clarify the role that homeowners play in decision-making during development and highlight the important relationships that exist between homeowners and urban forest professionals. 相似文献
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AIM：To study the electrophysiological effects of lidocaine on the myocardial tissue in guinea-pig left ventricular outflow tract under the conditions of hypoxia, acidosis and treatment with epinephrine. METHODS：The action potentials of pacemaker cells in guinea-pig left ventricular outflow tract were recorded by conventional technique with intracellular microelectrodes. The effects of lidocaine on the spontaneous slow response potentials were investigated under the conditions of hypoxia, acidosis and treatment with epinephrine (EPI). RESULTS：Lidocaine markedly decreased the rate of pacemaker firing (RPF), the velocity of diastolic depolarization (VDD), the maximal rate of depolarization (Vmax), the maximal diastolic potential (MDP) and the amplitude of action potential (APA). Lidocaine also shortened the 50% and 80% of duration of action potential (APD50 and APD80). At the concentrations from 0.1 μmol/L to 10 μmol/L, the effects of lidocaine were more significant. Under the condition of hypoxia and perfusion with deprived glucose content for 15 min, VDD, RPF, Vmax, MDP and APA significantly decreased, and APD50 notably shortened. Under the condition of hypoxia, lidocaine at 1 μmol/L significantly decreased VDD, RPF, Vmax and APA as compared with the cells treated with hypoxia only. Perfusion with pH 6.8 solution for 10 min, VDD, RPF, Vmax and APA significantly decreased, MDP notably increased, and APD50 and APD80 markedly shortened. Under the condition of acidosis for 10 min, lidocaine significantly decreased VDD, RPF and Vmax, and lengthened APD50 and APD80 as compared with the cells under the condition of acidosis alone. Perfusion with EPI at 10 μmol/L for 10 min resulted in significant increases in VDD, RPF, Vmax, MDP and APA, and notable shortenings of APD50 and APD80 were also observed. Compared with 10 μmol/L EPI group, 1 μmol/L lidocaine+10 μmol/L EPI significantly reduced VDD, RPF, MDP and APA, and lengthened APD50 and APD80. CONCLUSION：Lidocaine markedly decreases the autorhythmicity of the pacemaker cells in guinea-pig left ventricular outflow tract and influences the electrophysiological effects of hypoxia, acidosis and EPI. 相似文献
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以6年生曙光油桃/青州冬雪蜜桃为试材, 研究40℃、45℃、50℃高温短时间处理对油桃芽总酚含量、活性氧含量及相关酶活性和自然休眠解除的影响。结果表明: 40℃高温处理对油桃芽自然休眠的解除具有负调控效应(11月30日) 或效应不明显( 12月10日) , 其萌芽级数、·OH (羟基自由基)和O2· (超氧阴离子自由基) 产生速率、H2O2 (过氧化氢) 含量及POD (过氧化物酶) 、CAT (过氧化氢酶) 、PPO (多酚氧化酶) 活性均低于对照(11月30日) 或与对照无显著差异( 12月10日) , 而总酚含量和PAL (苯丙氨酸解氨酶) 、SOD (超氧化物歧化酶) 活性高于对照(11月30日) 或与对照差异不明显(12月10日) ; 45℃和50℃高温处理对油桃芽自然休眠的解除呈正调控效应, 其萌芽级数、·OH和O2· 产生速率、H2O2含量及POD、CAT、PPO活性与对照相比明显升高, 而总酚含量和PAL、SOD活性显著降低,虽然部分花芽和叶芽因高温处理而死亡, 但是在存活芽中短时间高温对油桃芽自然休眠解除的促进作用明显增强。总酚含量的降低和活性氧的迅速增加可能是高温解除自然休眠的原因。 相似文献
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桂花（Osmanthus fragrans Lour.）野生资源有非常丰富的性状和遗传变异,但目前被过度开发、破坏,导致分布范围急剧缩小,种群规模和数量锐减,生境片断化严重。以往的文献认为桂花起源于喜马拉雅山脉东段,即中国的西南地区;然而随着野生种群在湖南、浙江和福建等地被陆续发现,关于桂花自然分布的问题需要重新审视。作者在大量野外调研的基础上,结合前人研究结果,对桂花的自然分布和种群特征等进行了总结和概括,分析了野生资源与品种起源的关系,以期为桂花野生资源的有效保护和高效利用提供参考。 相似文献
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为了研究水平叶幕和直立叶幕所构成的微域环境对套袋葡萄果实花色苷代谢的影响,分别以棚架、篱架代表水平叶幕和直立叶幕,连续两年对棚架和篱架的‘摩尔多瓦’葡萄进行套袋,于果实膨大期开始实时监控果穗袋内微环境的温度和湿度;从转色期至果实成熟,测定不同发育阶段浆果果皮花色苷单体组分与含量,以及果皮花色苷代谢途径相关基因表达量与酶活性,分析果实品质差异。结果表明,2015年、2016年棚架水平叶幕下套袋果实袋内的高温极值及高温比例和湿度波动幅度与篱架直立叶幕套袋相比均有明显降低;连续两年成熟果实还原糖含量分别比篱架套袋的高18.33%和15.41%,且棚架的果实酸度较低;2015年测定棚架套袋果实的单宁及花色苷含量分别比篱架套袋的提高22.32%和35.29%,果实果皮红色度显著提高,而2016年夏季较冷凉,棚架套袋果实的总酚、黄烷醇、类黄酮含量分别比篱架套袋降低10.72%、10.97%和45.04%。2015年花后77 d,棚架套袋果实的花色苷单体含量较高,但到花后91 d时,篱架套袋果实花色苷单体含量补偿性增加。成熟果实果皮中均检测到21种花色苷单体,棚架套袋葡萄花色苷双糖苷化、甲基化及总修饰度均高于篱架套袋果实,但有19种花色苷单体含量低于篱架套袋果实。花后63~105 d,除Vv OMT外,棚架与篱架套袋葡萄花色苷代谢途径中Vv UFGT、Vv LDOX、Vv5GT和Vv PPO基因表达变化趋势一致,但相关酶活性差异较大。由此可见,水平叶幕可降低果实微域环境的温湿度,增加套袋果实品质及花色苷单体修饰程度,但降低花色苷单体含量,并影响花色苷代谢途径中相关酶基因的表达量及活性。 相似文献
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摘要：为高效防治西花蓟马，针对西花蓟马对不同寄主蔬菜及其不同部位叶片的选择性开展了系统的试验研究，其中采用组织培养法和笼罩法分别研究了西花蓟马对不同寄主蔬菜（黄瓜、辣椒、茄子、豇豆、番茄、芹菜、甘蓝）及其不同部位叶片的选择性。结果表明：在非选择性试验组，在番茄、黄瓜、甘蓝、豇豆上成虫着虫数均以中部叶片最多，分别为14.33、10.33、10.80头和10.00头；在辣椒、芹菜和茄子上若虫孵化数均以中部叶片相对最多，分别为0.33、0.20头和1.80头。在选择性试验组，番茄、芹菜、黄瓜、茄子上成虫着虫数均以上部叶片最多，分别为6.20、2.40、10.00头和4.40头；在甘蓝、茄子、黄瓜和豇豆上若虫孵化数均以中部叶片最多，分别为8.40、4.00、1.80头和1.20头。在组织培养法探究中，黄瓜上成虫着虫数最多（17.17头），茄子次之（4.17头），芹菜（2.00头）、甘蓝（2.00头）、辣椒（1.83头）和番茄（1.83头）上相对较少；若虫孵化数量以茄子（33.67头）上最多，黄瓜、甘蓝、番茄
次之，芹菜和辣椒上相对最少。在笼罩法探究中，成虫着虫数由多到少顺序依次为茄子（4.28头）＞黄瓜（4.25头）＞番茄（2.12头）＞甘蓝（1.72头）＞辣椒（1.35头）＞芹菜（0.78头），若虫孵化数由多到少顺序依次为茄子（33.67头）＞黄瓜（14.50头）＞番茄（0.83头），而辣椒、甘蓝、芹菜上没有若虫孵化。综合研究表明，西花蓟马成虫和若虫对黄瓜和茄子具有更强的偏好，其次是番茄、甘蓝、辣椒和芹菜，且西花蓟马优先选择在寄主蔬菜上部和中部叶片取食并产卵。 相似文献
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AIM: To investigate the effects of aspirin on the apoptosis of nasopharyngeal carcinoma cell lines CNE2R and CNE2 with different radioresistance and its potential mechanism. METHODS: The effects of aspirin on the cell viability, apoptosis, and protein levels of procaspase-3, cleaved caspase-3, procaspase-9, procaspase-12, PARP and cleaved PARP, PI3K p110α, Akt, Bcl-2, Bax and p27 in the CNE2R cells and CNE2 cells were detected by the methods of MTT assay, flow cytometry and Western blot. RESULTS: Aspirin inhibited the viability of homologous nasopharyngeal carcinoma cell lines CNE2 and CNE2R (with the IC50 to CNE2 cells of 6.18, 3.92 and 3.06 mmol/L for 24 h, 48 h and 72 h, respectively; and with the IC50 to CNE2R cells of 7.05, 3.90 and 2.20 mmol/L for 24 h, 48 h and 72 h, respectively). After treated with aspirin for 48 h, the apoptotic rate of CNE2R cells was higher than that of CNE2 cells (P<0.05). After treated with aspirin for 48 h, the protein levels of procaspase-3, procaspase-9, procaspase-12 and PARP were decreased, the protein levels of cleaved caspase-3, cleaved PARP and p27 were increased, and the protein levels of PI3K p110α, Akt and Bcl-2/Bax were decreased. CONCLUSION: Aspirin inhibits the viability of homologous nasopharyngeal carcinoma cell lines CNE2R and CNE2 with different radioresistance. Aspirin also induces the apoptosis of CNE2 and CNE2R cells, which is more effective in CNE2R cells. The underlying mechanisms may be involved in affecting PI3K/Akt signaling pathway, Bcl-2/Bax and p27 expression. 相似文献
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蔬菜的损失与浪费不仅造成了巨大的经济损失,同时对环境也造成了诸多负面影响。为了减少蔬菜全产业链的损失与浪费,助力食物系统可持续发展,对蔬菜的生产、产后处理、贮存、加工、流通、消费等环节的损失与浪费情况进行梳理,总结了全产业链损失和浪费率高、产后处理环节损失严重、减损潜力巨大等蔬菜损失与浪费的特征,分析了自然灾害、相关基础设施不足、供需信息不对称、非标准化操作、消费者偏好、不合理的消费行为等造成蔬菜损失与浪费的主要成因,阐述了蔬菜损失与浪费对资源和环境的影响,在梳理目前我国减少食物损失与浪费所采用的主要举措的基础上,提出了促进全产业链可持续发展的管理策略,包括多方合力制定减少食物减损行动方案、强化监管推进全链条减损标准建设、总结试点经验形成示范推广、加强教育引导文明健康消费理念等。 相似文献
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快速发展的我国园林绿化行业亟需科学的评价。20世纪80年代以来,我国园林绿化评价的研究呈现出不断增加的趋势,并成为风景园林学科研究领域的重点和热点问题。通过阐述国内园林绿化评价的研究进展,提出了园林绿化评价的概念、分类、意义和基本程序,归纳我国园林绿化评价的研究历程;总结园林植物评价、园林效益评价、园林绿化总体布局与结构评价的研究动态,剖析了研究的不足,并在此基础上提出了我国园林绿化评价研究的建议及展望,以期为推动我国园林绿化评价的研究及发展提供参考和借鉴。 相似文献