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21.
水蓼对汞积累与分布的水培实验   总被引:1,自引:0,他引:1  
钱建平  江文莹  张力 《生态学杂志》2012,31(8):2119-2124
通过水培实验,研究不同浓度的汞(0、0.5、1、10、20和50μg·L-1)对水蓼生长的影响及水蓼的耐受性表现。结果表明:在所处理的浓度范围内,水蓼生长与生理表现未受影响。水蓼根部具有最强的汞富集能力,富集系数高达531.5%。培养液中的汞浓度与水蓼茎、叶和根中汞的富集量呈显著正相关。在同一浓度时,随着培养时间的增长,水蓼体内汞含量不断增加。水蓼茎、叶和根亚细胞中的汞分布规律表现为:细胞壁>细胞器>细胞液,细胞壁对进入植物体内的汞有很强的束缚作用,限制其进入细胞质内部。  相似文献   
22.
为研究蓼科植物水蓼、火炭母体外抑菌效果,制备水煎煮液,测定其对枯草芽胞杆菌、大肠埃希菌、金黄色葡萄球菌、黑曲霉、青霉、酿酒酵母的抑菌圈直径、最小抑菌浓度及灭菌前后水煎煮液抑菌效果的变化。结果表明:当水蓼液浓度大于0.6 g/mL,火炭母液浓度大于0.2 g/mL时,2者对细菌的抑菌效果均依次为:金黄色葡萄球菌〉大肠埃希菌〉枯草芽胞杆菌。2种水煎煮液对3种真菌无抑制作用。火炭母液对3种细菌的最小抑菌浓度分别为1/8、1/16和1/64 g/mL,都比水蓼液的结果1/4、1/8和1/16 g/mL低。药液经121℃高压蒸汽灭菌处理后,水蓼液对3种细菌的抑制作用有所增强,火炭母液则对金黄色葡萄球菌的抑制作用有所增强。2种水煎煮液对3种细菌均有不同程度的抑制作用,可考虑以其为原料进行植物源抗菌剂的开发,拓宽其应用领域。  相似文献   
23.
昆虫拒食剂蓼二醛的合成及其对害虫的拒食活性   总被引:15,自引:0,他引:15  
张钟宁  方宇凌 《昆虫知识》2001,38(3):207-210
以 β-环柠檬醛为原料 ,经 6步合成了蓼二醛 ( ( -) -polygodial)的消旋体 ,总收率为 1 9 8% ;并合成了其甲胺衍生物。经生物活性测定 ,辣蓼的粗提物和合成的蓼二醛及其甲胺的衍生物对蚜虫和菜青虫有很好的拒食活性  相似文献   
24.
利用气相色谱-质谱联用仪对湘西辣蓼草中的挥发油化学成分进行了研究,共鉴定出53种组分.其主要成分为1-菲兰烯、1-异丙烯基-?-甲基苯、姜烯、α-苎烯、β-石竹烯、α-蒎烯、γ-松油烯、香柠檬烯、律草烯、红没药烯等.其中1-菲兰烯含量最高.约占挥发油总量的14%.  相似文献   
25.
Internal transcribed spacer (ITS) region of nuclear ribosomal DNA from 16 populations of Persicaria barbata (L.) H. Hara (Polygonaceae) belonging to five geographical locations of India (Arunachal Pradesh, Himachal Pradesh, Bihar, Karnataka and Andaman Island) was sequenced. Analysis of nucleotide sequences reveals polymorphism among the populations. UPGMA analysis conducted on the ITS datasets shows that the sampled populations of P. barbata are grouped according to their geographic locations and are supposed to be evolved under reproductive isolation which most probably are due to the long distance distribution and population fragmentation.  相似文献   
26.
Understanding plant phosphorus (P) assimilation and its root morphological responses is important to acquire an ideal material for remediation of P-enriched environments. Pot experiments were conducted to explore P accumulation and root morphological traits in a mining ecotype (ME) and non-mining ecotype (NME) of Polygonum hydropiper under different organic P (Po) sources (G1P, AMP, ATP, IHP) and inorganic P (Pi) source (KH2PO4), and also their responses to a high level of IHP for different growth periods. Both ecotypes showed higher biomass in Pi and IHP treatments than other Po sources. P accumulation in seedlings were in the order of Pi > IHP > other Po media. Extending the growth period increased biomass and P accumulation in both ecotypes. The ME demonstrated 1.11–1.46 times higher P accumulation than the NME. Seedlings fed with IHP demonstrated significantly greater morphological parameters of fine, medium, and thick roots compared to other Po sources. Total root length, surface area, and volume of both ecotypes significantly increased with the prolonged growth period. The ME has a higher ability to develop root system and exhibits better distribution of fine roots to enhance P accumulation from high P media, and thus it is a worthy material for P-phytoextraction.  相似文献   
27.
枫蓼肠胃康口服液HPLC指纹图谱研究   总被引:1,自引:0,他引:1  
建立了一种整体定性鉴别和指标成分定量的HPLC指纹图谱方法,对由牛耳枫和辣蓼两味药材组成的枫蓼肠胃康口服液原料及成品进行了指纹图谱研究,并测定了指标成分芦丁、金丝桃苷和异鼠李素的含量。采用Waters ODS C18色谱柱(250 mm×4.6 mm I.D.5μm),用含甲醇和甲酸溶液作为流动相,进行梯度洗脱,并对原料和成品的相应色谱峰进行归属鉴别。结果显示芦丁、金丝桃苷和异鼠李素得到了满意的线性范围,相关系数均大于0.999。按照SFDA的要求,对原料和成品的色谱指纹图谱采用相关系数法和夹角余弦法两种数学方法计算它们的相似度,两种计算方法相似度均不小于0.852。表明建立的枫蓼肠胃康口服液的定性定量方法显著优于传统的质量控制方法。  相似文献   
28.
采用固相微萃取法和水蒸气蒸馏法提取出贵州产辣蓼的挥发性成分,运用GC-MS联用技术对挥发性成分进行分析鉴定,并采用峰面积归一法确定各成分的相对含量。固相微萃取物中鉴定出48个化合物,主要有β-石竹烯(27.02%),正癸醇(14.39%),十二醛(12.96%)等,水蒸气蒸馏物中鉴定出27个化合物,β-红没药烯(19.00%),补身树醇(15.25%),十二醛(14.41%)等。辣蓼中挥发性成分经两种不同提取方法成分存在明显差异。与文献数据比较,不同省区产的辣蓼挥发性成分差异很大。体外抗菌试验表明,辣蓼挥发性成分具有抑菌作用,这些研究结果为辣蓼的有效利用提供了依据。  相似文献   
29.
The genus Koenigia L. emend. Hedberg (Polygonaceae)   总被引:2,自引:0,他引:2  
Pollen morphological studies revealed the occurrence of the characteristic spinulose pollen type of Koenigia not only in the three species earlier recognized in the genus (A" islandka, K. nepalensis and K. pilosd) but also in three additional species earlier treated under Polygonum , viz. K delicatula (Meisn.) Hara, K. forrestii (Diels) Mesicek & Soják, and A" nummularifolia (Meisn.) Mesicek & Soják. Further studies of flower morphology, fruit and petiole anatomy, basic chromosome number, etc., revealed additional similarities between those species, which led to a taxonomic revision of the genus Koenigia. This genus seems to be most closely related to Persicaria Mill, sections Cephalophilon (Meisn.) Gross and Echinocaulon (Meisn.) Gross, with Koenigia delicatula as a connecting link. There arc also interesting similarities with the genus Aconogonon (Meisn.) Rchb. Koenigia exemplifies the derivation from montane ancestors of a high mountain-dwelling genus displaying adaptive radiation to fit diverse alpine niches. Five species out of six are confined to high mountain areas in southeastern Asia, primarily in the Himalayas, whereas the sixth has spread to Arctic and alpine areas in the northern hemisphere and even penetrated to southern South America. The latter species shows progressive reduction in size in combination with adaptation to a very short summer under severe climatic conditions.  相似文献   
30.
In order to test the "anti-interference" hypothesis for adaptive significance of reciprocal herkogamy, patterns of illegitimate pollination and effects of self-pollen on the legitimate pollination and fertility were investigated in a naturally pollinated experimental population of distylous Persicaria japonica. Pollen deposition was compared among the emasculation treatments, i.e., emasculation of a single flower from individual inflorescences, emasculation of all the flowers of individual inflorescences, and no emasculation control. In both morphs, considerable illegitimate pollination was found to occur in all the treatments, and there was no significant difference in incompatible pollen load among the treatments. Therefore, it is suggested that herkogamy of P. japonica can sufficiently reduce both intraflower and intra-inflorescence self-pollinations, but not interinflorescence geitonogamous and-or interclonal illegitimate pollination. Measurements of pollen load after the repetitive pollen addition showed that space on the stigma surface may not limit the legitimate pollination under natural pollination conditions. Seed sets after legitimate pollination following prior self-pollination did not differ from the controls without self-pollination. Therefore, there is little possibility that incompatible pollen load interferes with either pollination or fertilization by compatible pollen, suggesting that "anti-interference" is unimportant for adaptive significance of reciprocal herkogamy at least in P. japonica.  相似文献   
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