濒危植物青檀的群落类型分析

青檀是中国特有的珍稀树种,具有很高的经济价值。以中国12个省市的19个野生青檀种群作为研究对象,分析了各生长地的气温、降水和光照条件,pH值及土壤的钙含量。并在此基础上,结合各地区青檀林中的物种情况,对青檀林植物群落类型进行了划分。研究结果表明,在温带半干旱地区,年平均气温约5-12％、年平均降水量约500mm、年日照时数局部超过2500h,土壤钙含量约5000mg／kg,土壤偏碱性,该地区青檀林多为青檀一金银木一卫矛植物群落;在温带季风区年平均气温约11℃、年平均降水量约600mm、年日照时数均超过2500h。局部地区土壤钙含量最高可达10000mg／kg,土壤呈碱性,该地区青檀林多为青檀一柘树植物群落;亚热带季风区中部及北部,年平均气温约16℃、年平均降水量约1200mm、年日照时教约2000h,局部地区土壤钙含量超过5000mg／kg,土壤pH值在5.2～7.9之间,该地区青檀林多为青檀-栾树-荩草植物群落;在亚热带季风区南部,年平均气温约19℃、年平均降水量约2000mm、年日照时数低于2000h,局部地区土壤钙含量普遍超过10000mg／kg,考察点土壤呈碱性,该地区青檀林多为青檀一密花树一金钱草植物群落。可以看出,不同地区青檀的群落类型有所不同。     

菰和菖蒲对重金属的胁迫反应及其富集能力

通过盆栽实验研究了Cu—Zn—Ph-Cd复合污染条件下,菰和菖蒲的生长状况、生理特性及吸收和富集重金属的能力。结果表明,高浓度污染下菰和菖蒲不能存活;低、中浓度中菖蒲的生长受到抑制,菰各生长指标与对照相比差异不显著,表明菰对低、中浓度重金属的耐性强于菖蒲。随着污染浓度的增加,菰和菖蒲叶片叶绿索含量显著降低;菰叶绿素a／b值略有降低,菖蒲叶绿素a／b值显著降低;菰和菖蒲叶片脯氨酸含量、相对电导率显著升高,超氧化物歧化酶（SOD）、过氧化物酶（POD）活性在低浓度时升高,中浓度时降低。菰体内重金属含量为Zn〉Cu〉Pb〉Cd,菖蒲体内的含量为Cu〉Zn〉Pb〉Cd,且二者体内的重金属含量都随着污染浓度的增加而升高。菰和菖蒲对Cd的富集系数较大,地上部分（茎与叶）和地下部分（根与根状茎）均大于1;对Pb的富集系数较小,地上部分和地下部分均小于1。菰和菖蒲地下部分重金属含量均高于地上部分含量,二者根系对4种重金属都有较强的滞留效应,平均滞留率均大于50％。各处理中菰对重金属的吸收量均高于菖蒲。综合分析菰和菖蒲的生长、生理及富集重金属的能力,菰比菖蒲更适用于低、中浓度重金属污染水体的生态修复。     

菰和菖蒲对富营养化水体净化效率的比较

研究了菰〔Zizania latifolia(Griseb.)Stapf〕、菖蒲(Acorus calamusL.)及它们的复合体系对富营养化水体的净化效果。结果表明,菰和菖蒲在供试富营养化水体中均能正常生长,二者单独种植体系或等量混合种植体系对富营养化水体均有一定的净化能力。单独种植的菰和菖蒲及二者的混合种植体系对供试水体中总氮的去除率分别为92.8%、92.7%和94.9%;对氨氮的去除率分别为95.5%、97.4%和96.6%;对总磷的去除率分别为83.9%、94.3%和84.7%;对CODCr的去除率分别为83.0%、85.5%和86.7%。单独种植的菖蒲对总磷的去除效果明显好于单独种植的菰和二者的混合种植体系。菰和菖蒲的混合种植体系对富营养化水体的净化效果与单独种植体系无明显差异。     

水菖蒲杀虫活性组分菖蒲螺酮的分离与鉴定（英文）

储粮害虫的危害造成储粮严重损失,化学农药的种种弊端使开发新型环境友好型药剂非常迫切, 植物由于其自身的特点, 成为开发新型药剂的重要来源。我们的前期研究表明, 水菖蒲Acorus calamus提取物对多种储粮害虫具有明显的触杀活性,并且分离得到了其主要活性组分β-细辛醚。本研究采用硅胶柱层析法,并以对玉米象Sitophilus zeamais的触杀活性进行追踪, 对水菖蒲提取物进行分离, 得到另一活性组分。经气相色谱-质谱联用、红外吸收光谱和核磁共振波谱方法鉴定,该活性组分为单体化合物菖蒲螺酮（1-异丙基-4,8-二甲基螺[4.5]癸-2,7-二酮）。将菖蒲螺酮以314.54, 251.63, 188.72, 125.82和62.91 μg/cm²的浓度处理玉米象96 h后, 玉米象的死亡率分别为85.6%, 72.2%, 53.3%, 38.9%和15.6%。处理96 h后,菖蒲螺酮对玉米象成虫的LD₅₀为158.00 μg/cm²。这些结果说明菖蒲螺酮对玉米象具有明显的生物活性,是水菖蒲提取物中除β-细辛醚以外的又一活性组分。     

不同种源青檀种子的营养成分及种子活力的差异

以采自安徽（ＡＨ）、山东（ＳＤ）及江苏（ＪＳ）的６个青檀（ＰｔｅｒｏｃｅｌｔｉｓｔａｔａｒｉｎｏｗｉＭａｘｉｍ．）种源种子为材料,测定各种源种子营养成分含量及种子活力。６个种源种子的蛋白质、可溶性糖、淀粉及粗脂肪含量存在较大差异。在种子品质上,６个种源的种子千粒重、浸泡液电导率及简化种子活力指数（ＳＶＩＳ）也存在显著差异。种子中各营养成分含量的高低与ＳＶＩＳ的大小密切相关,复相关系数达０８２２３,以蛋白质含量对ＳＶＩＳ的影响最大,淀粉和粗脂肪含量影响次之,可溶性糖含量影响最小。采用模糊聚类分析法,以种子千粒重、电导率及ＳＶＩＳ为评价指标,可将６个种源的种子品质划分为三大类：第一类包括ＳＤ１、ＡＨ１和ＪＳ１３个种源,种子品质较好;第二类仅为ＡＨ３种源,品质中等;第三类包括ＡＨ２和ＳＤ２２个种源,品质较差。     

菖蒲和石菖蒲的生长特性及其对生活污水净化功能的比较研究

以菖蒲和石菖蒲为对象,通过漂浮栽植研究了其在不同浓度生活污水中的生长特性及其对污水TN、NH3-N、TP、CODCr的去除情况。结果表明,菖蒲在中浓度污水中生长最好,其生物量显著高于低、高浓度,而石菖蒲在低浓度污水中生长最好,其生物量显著高于中、高浓度。菖蒲对中浓度污水中TN、TP、CODCr的去除率分别为96.85%、82.62%、88.89%,对低浓度污水中TN、TP、CODCr的去除率分别为99.87%、91.38%、83.34%,净化效果均高于高浓度(96.58%、80.96%、77.55%),但对NH3-N的去除率在高浓度污水中最好,为99.46%。石菖蒲净化中浓度污水的效果最好,对TN、NH3-N、TP、CODCr的去除率分别为94.20%、78.06%、89.43%、74.98%,对高浓度污水中的NH3-N、TP、CODCr的去除效果也较好,去除率分别为94.62%、91.95%、87.08%,但对TN去除率为59.14%,显著低于低浓度(98.73%)和中浓度(94.20%)。     

Volatiles from leaves and rhizomes of Fragrant Acorus spp. (Acoraceae)

Three horticultural selections of Acorus gramineus Soland were investigated to determine the chemical composition of their leaves and rhizomes. The variety 'liquorice' was found to contain methylchavicol (49%) which accounts for the unusual anisic odor of this variety, while beta-asarone was the main component of A. christophii (43%) and 'yodo-no-yuki' (20%). The results are compared with calamus oils, and the possible biosynthetic precursors of the main components methylchavicol and beta-asarone are considered.     

Impact of oxygen stress and energy availability on membrane stability of plant cells

This article reviews the relationship between the energy status of plant cells under O₂ stress (e.g. waterlogging) and the maintenance of membrane intactness, using information largely derived from suspension cultures of anoxia‐intolerant potato cells. Energy‐related parameters measured were fermentation end‐products (ethanol, lactate, alanine), respiratory rate, ATP, adenylate energy charge, nitrate reductase activity and biomass. ATP synthesis rates were calculated from the first four parameters. Reactive oxygen species were estimated from H₂O₂ and superoxide levels, and the enzymatic detoxification potential from the activity levels of catalase and superoxide dismutase. Structure‐related parameters were total fatty acids, free fatty acids (FFAs), lipid hydroperoxides, total phospholipids, N‐acylphosphatidylethanolamine (NAPE) and cell viability. The following issues are addressed in this review: (1) what is the impact of anoxia on membrane lipids and how does this relate to energy status; (2) does O₂ per se play a role in these changes; (3) under which conditions and to what extent does lipid peroxidation occur upon re‐aeration; and (4) can the effects of re‐aeration be distinguished from those of anoxia? The emerging picture is a reappraisal of the relative contributions of anoxia and re‐aeration. Two successive phases (pre‐lytic and lytic) characterize potato cells under anoxia. They are connected by a threshold in ATP production rate, below which membrane lipids are hydrolysed to FFAs, and NAPE increases. Since lipid peroxidation occurs only when cells are reoxygenated during the lytic phase, its biological relevance in an already damaged system is questionable.Key words: Acorus calamus L., energy shortage, free fatty acids, lipid peroxidation, lipolytic acyl hydrolase, lipoxygenase, membrane intactness, N‐acylphosphatidylethanolamine, O₂ stress, reactive oxygen species, Solanum tuberosum L.     

Enhanced atrazine removal by hydrophyte–bacterium associations and in vitro screening of the isolates for their plant growth-promoting potential

Emergent hydrophytes Acorus calamus, Typha latifolia, and Phragmites karka and epiphytic root bacteria isolated from their rhizoplanes were exposed to atrazine (5 and 10 mg l^?1) individually and in plant-bacterium combination for 15 days hydroponically. It was observed that A. calamus-Pseudomonas sp. strain, the ACB combination, was best in decontamination, showing 91% and 87% removal of 5 and 10 mg l^?1 atrazine. Plant-bacterium association led to significant increase in atrazine decontamination as compared to decontamination by either plant or bacterium alone, indicating a synergistic action of the hydrophytes and isolates which led to enhanced atrazine removal. To the best of our knowledge this is the first report on the potential of plant–bacterium combinations for atrazine decontamination. The isolates showed augmented growth in the presence of plants and were able to alleviate atrazine stress in them. These isolates exhibited plant growth-promoting traits such as auxin, siderophore, Poly(3–hydroxybutyric acid)/succinogycan, ammonia, catalase production and solubilization of inorganic phosphate in vitro. The use of plant-bacterium mutualistic symbiosis for atrazine mitigation is a relatively simple, inexpensive, and clean technique and this phytoremediation-rhizoremediation combination is suggested to be tried on field to establish their potential for clean-up of contaminated sites.