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1.
 Critical morphological synapomorphies have not been found in support of the Acoranan hypothesis, the molecular phylogenetic discovery that Acoranae are the basal monocots. The previously undetermined pattern of anther wall development in Acorus has been suggested to be one such character. Two main types of anther wall development have been recognized: 1) the “monocotyledonous” type, which characterizes both monocots and dicots, and 2) the “dicotyledonous” type, which is almost exclusively found among dicots. An anatomical study of anther wall development in Acorus was here undertaken using the electron microscope. Development of the anther wall in Acorus was found to be somewhat irregular or perhaps even intermediate between the two types although largely consistent with the “monocotyledonous” type. The presumed significance of anther wall development and other critical morphological characters to the Acoranan hypothesis in the absence of knowledge about the sister group to the monocots is evaluated. Received August 28, 2000 Accepted February 19, 2001  相似文献   
2.
Rhizomes of the marsh plant Acorus calamus (L.) and tubers of the flooding-intolerant Solanum tuberosum (L.) var. Bintje, both kept under strict anoxia, differ markedly in their fermentation properties. The fermentation capacities as measured by ADH and LDH activities and their respective product concentrations were estimated. While rhizomes of Acorus calamus, having high ADH and low LDH activities, accumulate mainly ethanol, tubers of Solanum tuberosum tend towards lactic acid fermentation. The total amount of adenine nucleotides is quite stable in Acorus calamus, whereas they show a sharp decline in S. tuberosum during the first 6h of anoxia. The adenylate energy charge of A. calamus recovers after a short initial drop (AEC > 0.8). AEC values of S. tuberosum decrease rapidly and remain at very low values (AEC ~ 0.3). Tuber tissues became soft and lost viability after about 48–72 h of anoxia at 25 °C. This might be due to tissue acidification and impaired energy metabolism, but not to the lack of energy reserves. Energy metabolism of A. calamus is well adapted to anoxia.  相似文献   
3.
为了探讨石菖蒲醇提物作为一种中药杀菌剂对病菌寄主植物本身防御酶体系的影响,该研究以番茄欧粉贝幼苗和川产道地中药石菖蒲为材料,采用冷浸法制备石菖蒲醇提物,经不同浓度石菖蒲醇提物对番茄幼苗进行处理,用比色法测定多酚氧化酶(PPO)、苯丙氨酸解氨酶(PAL)和过氧化物酶(POD)的活性,并利用GC-MS联用技术,对石菖蒲醇提物的主要化学成分进行定性分析。结果表明:第1天,醇提物浓度在0.04~0.08 g·mL~(-1)时,PAL活性显著高于对照;随后PAL活性随浓度升高降低;当浓度在0.04~0.16 g·mL~(-1)时,POD活性与对照无显著差异;浓度为0.32 g·mL~(-1)时,POD活性显著高于对照;浓度为0.64 g·mL~(-1)时,POD活性显著低于对照;当浓度在0.04~0.32 g·mL~(-1)时,PPO活性显著高于对照;浓度为0.64 g·mL~(-1)时,PPO活性与对照无显著差异;随着时间的延长,三种酶各处理组之间的差异逐步减少。第4天时,各处理组之间PAI,的活性无显著差异;当浓度为0.04 g·mL~(-1)和0.64 g·mL~(-1)时,PPO活性与对照无显著差异,其余范围均显著高于对照;当浓度在0.08~0.32 g·mL~(-1)时,POD活性数值上均高于对照。以上表明在一定浓度范围内醇提物可以增强防御酶活性,未破坏植物的防御酶体系。因此,该醇提物作为一种新型的中药杀菌剂有巨大的开发和利用潜力。利用GC-MS联用技术,可从醇提物中鉴定出30种化学成分,这些物质中多为苯丙素类物质,如β-细辛醚、α-(细辛醚和顺式甲基异丁香油酚等,其中含量最高的物质为β-细辛醚(42.48%)。这提示在后续的研究中,可针对β-细辛醚等醇提物的主要化学成分进行。  相似文献   
4.
为了确定石菖蒲(Acorus gramineus Soland)提取物对褐飞虱Nilaparvata lugens St1的活性及使用浓度,研究了石菖蒲提取物对褐飞虱的触杀毒力,30%石菖蒲乳油及30%石菖蒲扑虱灵混配乳油对褐飞虱的室内盆栽试验及大田试验防治效果。结果表明,石菖蒲提取物对褐飞虱3龄若虫及长翅型雌成虫处理48h后的LD50分别为0.64和0.95μg/头。室内盆栽试验表明:30%石菖蒲乳油30倍、30%石菖蒲扑虱灵混配乳油50倍施药3d后对褐飞虱3龄若虫的校正死亡率分别为85.56%和96.67%。30%石菖蒲乳油20倍、30%石菖蒲扑虱灵混配乳油300倍,施药7d后,对褐飞虱的田间防治效果分别为78.46%和79.76%。  相似文献   
5.
为了确定水菖蒲(Acorus calamus)活性成分β-细辛醚对玉米象Sitophilus zeamais Motschulsky的熏蒸活性,研究β-细辛醚对玉米象不同虫态的熏蒸作用。结果表明:β-细辛醚对玉米象4种虫态都有一定的熏蒸作用,其中对成虫的熏蒸效果最好,其次是卵,幼虫和蛹对β-细辛醚具有较高的耐药性。以质量浓度为200μL/L熏蒸卵120h后,卵的死亡率达到了99.09%。对幼虫和蛹的熏蒸作用不明显。对成虫熏蒸120h后,LC50为17.82μL/L。  相似文献   
6.
光照和生长阶段对菖蒲根系泌氧的影响   总被引:1,自引:0,他引:1  
王文林  王国祥  万寅婧  夏劲  唐晓燕  陈昕  梁斌  庄巍 《生态学报》2013,33(12):3688-3696
以自然湖泊沉积物为研究基质,利用微型电机控制溶氧微电极实现纵向精确微位移,在照光与遮光条件下,对典型湿地植物菖蒲幼苗、成株根系根基部起总根长1/4处(根1/4)、根系中部(根1/2)、从根基部起总根长3/4处(根3/4)及根尖(根1)处根系微界面径向溶氧浓度变化进行原位精确测定。结果表明:无论有无光照,菖蒲幼苗、成株根系不同部位均存在从根表面至沉积物氧饱和度由高到低的氧扩散层,其厚度0.18—0.68 mm;根1/2、3/4、1处氧扩散能力菖蒲成株较幼苗显著增强(P<0.01),根1/4处二者则无显著差异(P>0.05);光照对菖蒲幼苗、成株根系不同部位氧扩散能力的影响存在差异,光照对菖蒲幼苗根1/2及菖蒲成株根1/2、根3/4处影响显著(照光组显著高于遮光组,P<0.01),而对菖蒲幼苗根1/4、根3/4、根1及菖蒲成株根1/4、根1处无显著影响(P>0.05);从根系泌氧空间差异上看,照光条件下菖蒲幼苗、成株分别表现为根1/2>根3/4≈根1≈根1/4(P<0.01,P>0.05)和根1/2>根3/4>根1>根1/4(P<0.01),遮光条件下菖蒲幼苗、成株分别表现为根1/2≈根3/4≈根1≈根1/4(P>0.05)和根1/2>根3/4≈根1>根1/4(P<0.01,P>0.05)。  相似文献   
7.
通过对中国西南部3种菖蒲属(Acorus L.)植物(菖蒲A.calamus L.、石菖蒲A.tatarinowii Schott和金钱蒲A.gramineus Soland.)的细胞学研究,发现分布在运动及四川的9个菖蒲居群中,有5个居群为四倍体(2n=4x=44),4个居群为六倍体(2n=6x=66)。其中四倍体见于滇南及川西南;六倍体见于滇中及滇西北,并为首次报道。在云南及贵州分布的石菖蒲及金钱蒲5个居群均为二倍体。讨论了菖蒲分布区从二倍本、三倍体、四倍体和六倍体4种不同倍性居群的分布规律和可能的演化关系,六倍体居群的产生很可能喜马拉雅造山运动有关。  相似文献   
8.
运用气相色谱-质谱联用技术(GC-MS)对安徽4个不同地区石菖蒲中挥发油成分进行分析,并对其质量进行评价。结果显示,皖南山区、大别山区、安庆及芜湖地区石菖蒲挥发油中依次分别鉴定出45、52、48、54种化合物,共同化合物为25种,各产地已鉴定的25种共同化学成分含量分别占各自总成分的93.27%、84.75%、90.73%、92.84%,其中含量最高的β-细辛醚含量占比依次为54.73%、50.12%、57.24%、60.15%,其次α-细辛醚依次为32.18%、30.14%、28.15%、26.15%,4个地区石菖蒲挥发油中均不含黄樟醚。不同地区石菖蒲中挥发油化合物存在一定差异,安徽地区石菖蒲安全性均较高且大别山区石菖蒲最为优质。  相似文献   
9.
BACKGROUND AND AIMS: The anatomical structure and development of adventitious roots were analysed in the basal monocotyledon, Acorus calamus, to determine to what extent those features are related to phylogenetic position. METHODS: Root specimens were harvested and sectioned, either with a hand microtome or freehand, at varying distances from the root tip and examined under the microscope using a variety of staining techniques. KEY RESULTS: Roots of Acorus calamus possess a unique set of developmental characteristics that produce some traits similar to those of another basal angiosperm group, Nymphaeales. The root apical meristem organization seems to be intermediate between that of a closed and an open monocotyledonous root apical meristem organization. The open-type root apical meristem consists of a curved zone of cortical initials and epidermal initials overlying the vascular cylinder initials; the epidermal part of the meristem varies in its association with the cortical initials and columellar initials of the promeristem. The cortex develops an endodermis with only Casparian bands, a dimorphic exodermis with Casparian bands and suberin lamellae, and a polygonal aerenchyma by differential expansion, as also observed in the Nymphaeales and some dicotyledonous species. The stele has characteristics like those of members of the Nymphaeaceae. CONCLUSIONS: Specific anatomical and developmental attributes of Acorus roots seem to be related to the phylogenetic position of this genus.  相似文献   
10.
Calamus (Acorus calamus L., Araceae) is an aromatic herb, indigenous to Central Asia and Eastern Europe. The fragrant oils obtained by alcoholic extraction of the rhizome are mainly used in the pharmaceutical and oenological industries. Nevertheless, the occurrence of beta-asarone [(Z)-1,2,4-trimethoxy-5-prop-1-enyl-benzene] limits the possibility of its use due to the carcinogenic properties of this compound. The aim of this work was to identify a diploid beta-asarone-free A. calamus by using chemical and molecular approaches. For these purposes alcoholic extracts of both diploid and triploid A. calamus were analyzed by gas chromatography-mass spectrometry (GC-MS) and comparison of the 700 bp sequence of the non-transcribed spacer (NTS) in the 5S-rRNA gene was also performed. Alcoholic extracts of the triploid A. calamus were characterized by a higher percentage of beta-asarone (11%), which was the main compound, followed by higher percentages of camphene (2.27%), E-beta-ocimene (3.28%), camphor (1.54%), calarene (1.42%), alpha-selinene (5.02%) and tau-cadinol (2.00%), when compared to the diploid A. calamus. The latter had higher percentages of iso-shyobunone (8.62%), beta-sesquiphellandrene (3.28%), preiso calamendiol (22.81%) and acorone (26.33%), and completely lacked of beta-asarone. The 5S-rRNA spacer region of both diploid and triploid A. calamus were amplified by PCR using a pair of primers located at the 3' and 5' ends of the coding sequence of 5S-rRNA gene. The resulting PCR products (about 700 bp) were gel purified, subcloned into pGEM-T Easy vector and sequenced. By aligning the isolated nucleotide sequences of the two varieties and the sequences from different A. calamus chemotypes present in Genbank, sequence diversities were found in the spacer region. Furthermore, the PCR products were digested by using EcoRI. The restriction profile of the spacer domain resulted different for the two cytotypes. Along with chemical analysis of alcoholic extracts, sequence analysis coupled to restriction mapping was demonstrated to represent a powerful tool to distinguish the A. calamus diploid cytotype from the others. The security and effective usage of the diploid beta-asarone-free A. calamus was also discussed.  相似文献   
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