高职院校学生《园林植物学》学习兴趣培养探析

根据高职院校的人才培养定位,针对《园林植物学》的课程特点,结合课程教学要求,为切实提高学习效果,提出了提高学生学习兴趣的几点建议,以期为其他理论性较强的课程教学提供参考。     

基于Lefkovitch矩阵模型的山酢浆草种群动态分析

依据林下多年生草本植物山酢浆草Oxalis griffithii的形态学特征,将其生活史划分为4个阶段,并根据3种生境下山酢浆草种群的野外调查资料建立了不同种群的Lefkovitch结构矩阵模型,在此基础上预测了山酢浆草种群的动态及其阶段结构的变化;同时,运用敏感度、贡献率指标分析了影响种群动态的关键生活史阶段。结果表明：不同生境下山酢浆草种群的动态发展趋势不尽相同,常绿阔叶林下的种群（MD）呈稳定发展状态,其他2种生境下种群表现出衰退的发展趋势;种群的动态变化过程受个体的生长、残存、萎缩和繁殖等的综合影响;不同生活史阶段对种群动态的影响差异显著,种群动态过程及其发展趋势主要受种群内较大阶段个体的影响。图2表5参19     

Chemical analysis of Teucrium species (Lamiaceae) growing on serpentine soils in Bulgaria

Trace elemental concentrations (Fe, Ni, Mn, Cr, Co, Cu, Zn, Pb, Cd, and As) in aerial biomass (stems, leaves, and flowers) of the medicinal plants Teucrium chamaedrys, T. montanum, and T. polium growing on serpentine soils in Bulgaria were examined in relation to the total element contents in their respective rhizospheric soils. The objectives of the study were to evaluate: (1) elemental concentrations in plant tissues and associated soil samples together with the plants ability to tolerate/accumulate metal concentrations; (2) correlations between total metal concentrations in plants and their rhizospheric soils. Metal concentrations varied across species and sites. Their levels in plant tissues from nonserpentine sites were always lower compared to those from serpentine ones. The highest concentrations for Fe, Ni, Mn, Cr, As, Cu, and Pb were found in T. polium. Positive correlation coefficients were established between Ni, Cr, Fe, Co, and Cu in plants and Ca in the soil. None of the species tested hyperaccumulated metals although the metal concentration in some of them exceeded the range naturally found in plants. The Teucrium species can be considered as “excluders”, containing relatively low metal concentrations in their aerial parts (stems, leaves, and flowers) even in cases of high elemental concentrations in the rhizospheric soil. In all three medicinal plants, metal concentrations for toxic elements were above the permissible limits for pharmaceutical purposes. Therefore, plants found on serpentine bedrock are not recommended to be collected for pharmaceutical purposes.     

Research Progress on Speciation of Selenium Compounds in Plants

All factors affecting the PCR system in Pinus massoniana Lamb were investigated one by one.The results show that the optimum PCR system of EST-SSR were:2μL 10×Buffer(Mg²⁺ Free), 30 ng template DNA,0.187 5 mmol/L dNTPs, 3.75 mmol/L Mg²⁺,8 pmol primer pair,1.0 U Taq DNA poly-merase in total 20μL reaction system. Finally,a total of 11 isolates of P.massoniana was used for testing the stability of the PCR amplification.The results prove that the optimum PCR system was stable,reliable,highly repetitive.     

毛果垂枝泡花树——浙江清风藤科一新变种

报道浙江清风藤科Sabiaceae一新变种，即毛果垂枝泡花树Meliosma flexuosa vat．pubicarpa X．F．Jin，Hong Wang＆．H．W．Zhang。此新变种与原变种垂枝泡花树M．f.vat．flexuosa的主要区别在于核果被褐色短柔毛。文末还附有新变种与浙江产泡花树属Meliosma近似种的检索表。     

蜡梅花粉活力检测方法筛选及保存时间观察

用氯化三苯基四氮唑(TTC)法、无机酸法和离体萌发法等3种测试方法检测不同蜡梅Chimonanthus praecox品种的花粉活力。结果表明:TTC法和无机酸法检测效果较差,而经过改良的培养基离体萌发法能有效地检测蜡梅花粉活力。该实验条件下,蜡梅花粉离体萌发最佳培养基为聚乙二醇(分子量6 000)300 g.kg-1 硼酸100 mg.L-1。在20℃暗培养条件下,品种大金星‘Dajinxing’、圆被素心‘Rotunbaticoncolor’和金龙紫穴‘Jinlong Zixue’的萌发率分别为64.4%,35.8%和35.5%,不同蜡梅品种花粉活力差异较大。室温露置条件下,蜡梅花粉活力能保持18~19 d,而经干燥后,在密封冷藏条件(4±2℃)下能保持2个月左右。图3表2参11     

北京雾灵山自然保护区胡桃楸群落结构

采用典型性样方法对北京雾灵山自然保护区的胡桃楸Juglans mandshurica群落进行了调查,并进行了群落结构特征及物种多样性的分析。结果表明:胡桃楸群落内维管束植物达156种,隶属于55科111属;植物区系以北温带类型的种类为主,其属数占群落内植物总属数的35.14%,东亚、泛热带等成分明显较少。乔木层物种数较少,只有13种;群落内植物的生活型以地面芽植物最多,为53种,其次是1年生草本,地上芽植物最少。乔木层物种多样性最低,草本层最高;群落内物种多样性与胡桃楸的重要值呈负相关,但不显著;只有群落内穿山龙Dioscorea nipponica与披针叶薹草Carex lanceolata和龙芽草Agrimonia pilosa分别达到了显著相关。表7参20     

雷公藤属植物生物学特性与生态适应性的初步研究

历时4 a,调查了我国27个县(市)雷公藤属Tripterygium种质资源,建立种质资源收集库,定期观察雷公藤母本及无性系表型性状和生态适应性。结果表明,不同种质雷公藤的萌蘖性、生长势与造林成活率均存在差异,雷公藤T.wilfordii萌蘖性能明显优于昆明山海棠T.hypoglaucum,野生植株、种质资源收集库内母本及无性系后代均表现一致;在浙江丽水低海拔地区栽培,雷公藤造林成活率和幼林生长势也明显优于昆明山海棠。浙江类似地区雷公藤药材栽培应优先选用雷公藤,良种选育重点在雷公藤分布区内进行,既可提高良种选育效率,又可保证选育的良种适合丽水地区环境条件。表4参5     

舟山海岛野生观赏植物的应用

通过对舟山群岛植物资源的调查研究,分析了耐盐碱植物、耐干旱瘠薄的阳性植物、耐阴植物和彩叶植物等海岛野生观赏植物的资源种类和特点,论述它们在营建沙滩风景林、海岛植物群落及园林绿化中的应用前景和方法.针对目前舟山海岛野生观赏植物开发应用不足,缺乏地方特色等现状,提出了合理开发野生观赏植物,筛选沙滩风景林树种和规划营造海岛群落景观等方面的建议,特别强调应采用海岛特色植物以体现海岛城市风格.参10