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空心莲子草的化学成分研究 总被引:2,自引:0,他引:2
用硅胶柱层析和凝胶柱层析对药用植物空心莲子草Alternanthera philoxeroides (Mart.)Griseb全草的石油醚提取物进行分离纯化,从中分离得到7个化合物,通过波谱学数据和已知化合物数据作比较,分别鉴定为2-羟基-3-甲基-蒽醌(2-hydroxy-3-methyl-anthraquinone,1),2-羟基-1-甲氧基-蒽醌(2-hydroxy-1-methoxyl-anthraquinone,2),二十四烷酸α-单甘油酯(tetracosanoic acid 2,3-dihydroxypropyl ester,3),二十六烷酸α-单甘油酯(hexacosanoic acid 2,3-dihydroxypropyl ester,4),十八烷酸α-单甘油酯(monostearin,5),△5,22-豆甾烯醇-3-O-β-D-葡萄糖苷-6′-棕榈酸酯(△5, 22-stigmast-3-O-β-D-glucopyranosyl-6′-hexadecanoate,6),豆甾醇-3-O-β-D-吡喃葡萄糖苷(stigmasterol-3-O-β-D-glucopyranoside,7).化合物1和2为首次从该植物中分离得到,3~6均首次从该属植物中分离得到. 相似文献
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为了解空心莲子草叶甲Agasicles hygrophila被引入中国20多年后其取食行为与取食能力是否发生改变, 我们通过采集叶甲自然种群的成虫, 在室内用空心莲子草Alternanthera philoxeroides饲养获得检测用叶甲各虫态与虫量进行室内定量检测, 研究了空心莲子草叶甲自然种群各龄幼虫与成虫在不同密度下对空心莲子草的控害效果。结果显示: 1龄幼虫喜食顶芽嫩叶, 在每株接0.2和1头1龄幼虫密度下, 空心莲子草仍有新叶和侧芽生成, 生物量、 株高与茎节数仍在增加; 在5头/株的密度下, 空心莲子草的生物量、 叶片数和侧芽数均出现负增长; 在10头/株的密度下, 草的生物量、 株高、 叶片数、 侧芽数和茎节数均表现为负增长。2龄幼虫优先取食顶芽嫩叶, 也取食老叶与茎杆, 在每株10头2龄幼虫的密度下, 接虫7 d后, 40%的植株死亡。3龄幼虫取食叶片与茎秆, 后期钻入茎秆中化蛹,在10头/株密度下,7 d后, 已引起52%的植株死亡, 存活株的茎节数显著减少。成虫可24 h连续取食植株的任何组织, 0.2头/株的密度下,空心莲子草叶片与侧芽数量已呈现负增长; 5头/株的密度下,空心莲子草的生物量、 株高、 叶片数、 侧芽数与茎节数均呈现较大的负增长; 10头/株的控草效果更加显著。 相似文献
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为探讨全寄生植物南方菟丝子(Cuscuta australis)防治入侵植物空心莲子草(Alternanthera philoxeroides)的可行性,以二者野外天然生长的种群为研究对象,分析南方菟丝子寄生对空心莲子草生长及防御的影响,阐明空心莲子草在受到寄生胁迫时如何权衡自身生长与防御的关系,进而发展出一套应对南方菟丝子寄生的生长-防御策略。结果显示:(1)南方菟丝子寄生显著改变空心莲子草茎的形态,茎直径和平均节间长均增加,茎直径变化极显著(P0.01);(2)南方菟丝子寄生显著减少空心莲子草叶片数,但同时显著增加后者茎的分枝数,而茎上的节是潜在的无性繁殖体,故有利于空心莲子草的克隆繁殖;此外,南方菟丝子寄生显著降低了空心莲子草的根、茎、叶生物量和总生物量,抑制空心莲子草的生长;(3)南方菟丝子寄生显著增加空心莲子草茎的单宁、总酚、三萜皂苷含量,增强其防御能力;(4)南方菟丝子寄生的空心莲子草的生物量与茎部木质素、三萜皂苷、单宁和总酚含量均呈现显著负相关性(P0.01),对照组则不存在相关性;且寄生组较对照组相比,生物量的相对百分比显著低于对照组(P0.01),而用于防御的次生代谢产物总含量的相对百分比显著高于对照组(P0.01)。以上结果表明,受到南方菟丝子寄生胁迫后,空心莲子草改变自身的生长-防御策略,减少营养生长投入而将更多的资源投向克隆繁殖,同时增强对\"防御\"物质的投入,增强其防御能力,以利于后代生存和繁衍。 相似文献
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空心莲子草中氨基酸的分析 总被引:2,自引:0,他引:2
从空心莲子草中提取分离到一组氨基酸,经氨基酸自动分析仪分析鉴定为丝氨酸、谷氨酸、甘氨酸等10种氨基酸。其中以谷氨酸含量最高,丝氨酸含量最低,并且有5种人体必需氨基酸。 相似文献
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笔者采集到空心莲子草、南瓜、繁缕等多种植物的茎进行对比实验发现:苋科植物空心莲子草(Altemanthera philoxemides)的茎是观察植物导管的好材料。现介绍如下: 相似文献
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空心莲子草是入侵我国的重要杂草之一,它在我国能广泛传播和迅速蔓延,与其自身特有的形态生理适应性、强大的繁殖特性和竞争力,以及传入地缺乏自然控制机制密切相关.空心莲子草从其原产地过渡到新的侵入地的过程中,在生态环境适应方面发生重大变化,产生一系列的形态结构、生理过程,以求适应陆地生活条件.其表型可塑性使得空心莲子草有更宽的生态幅,可利用的潜在资源范围也随之扩展;强大的营养繁殖能力,使其迅速产生大量的后代,在失去自然天敌调控的情况下,尤为适应其侵入种的生长、繁殖、发展和传播,种群数量的激增又会加速其传播扩散速度,导致空心莲子草爆发成灾.在综述空心莲子草在形态、生理、繁殖的适应性特征及天敌因素和入侵特性的基础上,根据前人的有关论述,分析了空心莲子草在我国的适应性特征及入侵机制,指出了空心莲子草在我国适应性及入侵机制应着重研究的方向,提出了综合治理和充分利用空心莲子草的对策. 相似文献
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空心莲子草K~+吸收的动力学研究 总被引:6,自引:0,他引:6
溶液培养120~180天的空心莲子草的最大吸K_+速率为1.8~2.1μmol·g~(-1) FW·h~(-1);K_m值8.0~14.0μM,比一般农作物的都小;开始在体内累积K~+的外液K~+浓度小于0.2μM。空心莲子草在自然土壤和水体环境中能较快地富集钾素。 NH_4~+浓度100μM以上对K~+吸收有显著抑制作用,和对照相比抑制达50%以上,而Na~+则需大于500μM时才对K~+吸收有显著影响。 相似文献
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Effects of soil heterogeneity and clonal integration on Alternanthera philoxeroides populations with a radial ramet aggregation
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Some clonal plants can spread their ramet populations radially, and soil heterogeneity and clonal integration may greatly affect the establishment of these types of populations. We constructed Alternanthera philoxeroides populations with a radial ramet aggregation, allowing old ramets of clonal fragments to concentrate in central pots and younger ramets to root in peripheral pots. The peripheral pots were supplemented either with three different levels (high, medium and low) of soil nutrients to simulate a heterogeneous soil environment, or only one medium level of soil nutrients to simulate a homogeneous environment. Stolon connections between the central older ramets and the peripheral younger ramets were left intact or severed to test the effect of clonal integration. The maintenance of stolon connection could induce the division of labor between different‐aged ramets, by increasing the root investment in central ramets and the above‐ground growth in peripheral ramets. The maintenance of stolon connection could improve the growth of the central and peripheral ramets, clonal fragments and even the whole population. However, the positive consequence in peripheral ramets and whole fragments was only detected in the high‐nutrient patch of heterogeneous treatment. In sum, in the population with the radial ramet aggregation, clonal integration can play a key role in the rapid recruitment of young ramets of A. philoxeroides fragments, as well as the expansion of the whole population. The magnitude of clonal integration also became more obvious in the peripheral young ramets and whole fragments that experienced high‐nutrient patches. 相似文献
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Nitrogen addition increases intraspecific competition in the invasive wetland plant Alternanthera philoxeroides,but not in its native congener Alternanthera sessilis
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AO Wang Xing‐Xing Jiang Qiu‐Qiu Zhang Jian Zhou Hong‐Li Li Fang‐Li Luo Ming‐Xiang Zhang Fei‐Hai Yu 《Plant Species Biology》2015,30(3):176-183
Nitrogen is often released in pulses with different frequencies, and N supply pulses may affect growth, reproduction, and biomass allocation of plants. However, few studies have examined how N supply pulses affect intraspecific competition of clonal plants and whether such an effect depends on the N supply amount. We grew one (no competition) or 12 ramets (with intraspecific competition) of both an invasive clonal plant Alternanthera philoxeroides and its native congener Alternanthera sessilis in five different N treatments: control (no N addition), low/high amount with low/high frequencies (pulses). Nitrogen addition significantly increased the growth of both species, while intraspecific competition decreased it. Nitrogen addition significantly increased intraspecific competitive intensity of A. philoxeroides as measured by the log response ratio of growth traits, but did not affect that of A. sessilis. Despite the N supply amount, N pulses had little effect on the growth and thus intraspecific competition of the two species. Therefore, increasing N deposition may change population structure and dynamics and the invasion succession of A. philoxeroides, but changes in N pulses may not. 相似文献
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重金属胁迫条件下空心莲子草的生长和营养特征分析 总被引:1,自引:0,他引:1
空心莲子草是一种常见的水生植物,并能在重金属污染的水体或附近土壤中生长.本研究发现,空心莲子草能富集6种常见的重金属元素,其富集能力为:Zn2+>Mn2+>Pb2+>Cu2+>Cd2+>Cr3+.高浓度(1 mmol/L) Cu2+、Mn2+、Zn2+和Cr3+ 等重金属胁迫处理条件下,空心莲子草的根冠比增加,生物干重、总根长和总根表面积都相应降低.此外,高浓度(1 mmol/L) Pb2+、Cd2+、Cu2+或Zn2+分别胁迫处理条件下,空心莲子草的K+、Ca+和Mg+等元素的含量变化差异显著(P<0.05).以上研究表明,空心莲子草通过改变体内钾钙镁等重要生长元素营养情况来适应重金属污染的胁迫,有很强的富集重金属元素的能力,进而降低污染、净化水体.空心莲子草对重金属污染的生长响应及体内重要矿物元素营养特性之间的相互关系,可能为重金属污染的水土生物修复提供理论依据. 相似文献
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Few studies have examined the effects of clonal integration (translocation of resources between interconnected ramets) during the expansion of amphibious clonal plants from terrestrial to aquatic habitats. We conducted a greenhouse experiment to simulate the expansion of plants from terrestrial to contaminated aquatic habitats in the amphibious stoloniferous herb Alternanthera philoxeroides (alligator weed). The proximal ramets (i.e. relatively old) of clonal fragments grown in uncontaminated soils were connected to (allowing clonal integration) or disconnected from (preventing clonal integration) distal ramets (i.e. relatively young) grown either in uncontaminated water (control, no CuSO4) or in four copper‐contaminated water treatments containing 31.25, 62.5, 125 and 250 mg/L CuSO4, respectively. When a stolon connection was severed, all distal ramets grown in the contaminated water died. When the stolon connection was intact, however, the survival rate of the distal ramets was 85–100% when they were grown at the three lower levels of contamination and 43.75% at the highest level. Moreover, the survival rate and growth of the distal ramets grown in the three lower levels of contamination treatments did not differ from those in the control (uncontaminated water). These results suggest that clonal integration could greatly improve the survival and growth of alligator weed subjected to moderate levels of copper stress. Although clonal integration could also increase the survival rate of the connected distal ramets subjected to the highest level of copper stress (250 mg/L CuSO4) compared with that of disconnected distal ramets, the survival rate and growth measures were still significantly lower than those in the control. This suggests that clonal integration plays a limited role in the survival and growth of alligator weed when it is subjected to severe stress by high levels of copper contamination. 相似文献
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入侵植物喜旱莲子草——生物学、生态学及管理 总被引:17,自引:0,他引:17
喜旱莲子草Alternanthera philoxeroides原产于南美洲,属于苋科Amaranthaceae莲子草属Alternanthera。一百多年来,该物种通过压舱水或军马饲料被传播到北美洲、大洋洲、欧洲,以及东南亚和中国等地,成为暖温带-热带湿润气候区淡水生态系统的重要外来入侵种。本文结合对喜旱莲子草在原产地的分布状况的考察、原产地和入侵地喜旱莲子草的比较研究,以及入侵生态学研究的最新成果,对该物种在原产地的地理分布和种内变异、生活史特征、入侵机制和控制策略等方面进行评述,以提高我国科研人员对这一外来入侵种的认识,为科学管理和控制提供依据。 相似文献
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盐胁迫对空心莲子草生长和光合作用的影响 总被引:5,自引:0,他引:5
用NaCl浓度为0(对照)、50、100、150、200、250、300、350mmol/L处理空心莲子草[Alternantheraphiloxeroides(Mart.)Griseb]。结果表明:盐胁迫下,植株鲜重、干重和根冠比都下降,含水量和肉质化程度先略高于对照,而后逐渐下降;根、茎和叶中Na 含量呈上升趋势,而K 含量呈下降趋势,且在同一浓度的盐处理下,叶的Na 和K 含量最高,茎的次之,根的最低;游离氨基酸(free amino acid,FAA)逐渐减少,脯氨酸(proline,Pro)含量先略低于对照,而后则急剧上升,可溶性糖含量(soluble sugar,SS)的变化正相反;净光合速率(net photosynthetic rate,Pn)、气孔导度(stomatal conductance,Gs)和蒸腾速率(transpirationrate,Tr)呈下降趋势,胞间CO2浓度(intercellular CO2concentration,Ci)呈上升趋势;膜稳定性呈下降趋势。因此,空心莲子草是一种盐生植物,且最适盐浓度较低;Na 主要积累在地上部的茎和叶中。推测它有可能向盐渍土壤蔓延。 相似文献
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Cd2+污染水质对水花生根系抗氧化酶活性和超微结构的影响 总被引:11,自引:1,他引:11
在不同浓度Cd^2 污染下,水花生根中超氧化物歧化酶(SOD)和过氧化氢酶(CAT)的活性呈现先升后降的变化,但达到最大值时的Cd^2 污染浓度,SOD的更低,过氧化物酶(POD)的活性和可溶性蛋白含量呈现持续下降的变化趋势,可溶性蛋白的含量受Cd^2 的毒害更大。随着Cd^2 污染浓度的增加和胁迫时间的延长,根尖细胞中高尔基体消失,线粒体嵴突膨胀、变形及空泡化,细胞核扭曲成不规则形,核染色质凝集,这些变化反应在功能上表现为膜脂过氧化、能量供应不足,蛋白质合成受阻而含量下降,最终导致死亡。各项结果与Cd^2 皆表现出明显的剂量效应关系,污染浓度愈大毒害程度愈深。 相似文献
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《Journal of Plant Interactions》2013,8(1):194-199
Bioinvasion has become a serious environmental problem in the world in general and is considered the second biggest threat to biodiversity. Alternanthera philoxeroides is widely distributed and causes the most serious threat to biodiversity in China. The traditional physical or biological control methods are not effective in controlling the invasion and extension of A. philoxeroides. In the present paper, some physiological characteristics of Humulus scandens and A. philoxeroides were investigated in the field and laboratory. The results showed that H. scandens is more competitive than A. philoxeroides, the competitive rate (CR) of H. scandens against A. philoxeroides was 9.834. Additionally, the leaf, stem, and root biomass of A. philoxeroides decreased significantly when the two species co-occurred. Thus, the invasive abilities of these two invasive plants are different and H. scandens strongly inhibited the growth of A. philoxeroides. Moreover, as an annual herb, H. scandens can be easily eliminated by harvesting before its seeds mature. The result suggests that sowing seeds of H. scandens in the habitats invaded by A. philoxeroides could be an ideal biological control method. 相似文献