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1.
Abstract The effects of physiological integration on clone behaviour are examined at various structural scales, using data from the stoloniferous herb Glechoma hederacea . The consequences for clone expansion of traumatic fragmentation of the connections between clonal ramets are also illustrated. These results, together with information from other species, are used to refute the commonly-quoted view that physiological integration between the ramets of clonal herbs evens out the effects of variation in environmental quality, and promotes equitable ramet performance. Instead, clonal species are responsive, at a variety of structural scales, to environmental quality. Therefore, in a heterogeneous habitat, within-clone variation in the performance of ramets and clonal sub-structures is to be expected. The seminal study which purports to demonstrate environmental averaging in clonal herbs is shown to be both inadequately designed and inappropriately analysed to accomplish its aim.
Physiological and architectural reasons for the local responses to environmental quality seen in the majority of clonal herbs are discussed.  相似文献   

2.
紫苏与白苏不同化学型挥发油成分的研究   总被引:19,自引:0,他引:19  
本文对不同地区的八个紫苏、白苏样品进行了植物形态与挥发油化学成分的对比研究。花为白色、植物全绿者其挥发油主要成分为紫苏酮,此植物为紫苏酮型。花为淡紫色,植株全紫者(老叶叶面为绿色,叶背面为紫色)其挥发油的主要成分为紫苏醛,此植物为紫苏醛型。花为粉白色,叶子面绿背紫绿色或者叶绿,叶柄、茎为紫绿色者其挥发油主要成分为莳萝油脑或肉豆蔻醚,此植物为苯丙烯基型。  相似文献   

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An automated method for rapid and convenient measurement of L-glutamate has been developed by using a discrete analyzer, EEL Auto Chemist. It is based on the colorimetric measurement of NADH produced on a mole-mole basis by enzymatic dehydrogenation of L-glutamate using L-glutamate dehydrogenase from bovine liver. The values of L-glutamate obtained by this method were well agreed with those obtained by the routine Waruburg mano-metric method using L-glutamate decarboxylase from Escherichia coli.  相似文献   

5.
The overproduction of tumor necrosis factor-α (TNF-α) was suppressed by orally administering a perilla leaf extract (PLE). When mice were successively injected with OK-432, severe TNF-α was induced in the serum, but this elevated TNF-α level was reduced after an oral administration of PLE (400 μl/mouse). Oral administration of PLE also inhibited TNF-α production that was induced by muramyl dipeptide (500 μg/mouse) and OK-432 (3 KE/mouse). These characteristics were obtained from all strains of perilla. The inhibitory activity against TNF-α production was heat-stable, and the existence of several active molecules was suggested. When PLE was passed through an ultrafilter, the inhibitory activity against TNF-α production was collected in those fractions with a mass of 0.5 to 1 kDa and more than 10 kDa. When PLE was solvent-extracted, the strongest activity was recognized with aqueous preparation, although significant activity was also detected in preparations extracted with n-hexane and ethyl acetate. These findings suggest that the daily use of certain functional foods may be useful for controlling the host defense system.  相似文献   

6.
我国为世界三大高氮沉降区之一,氮沉降严重影响了植物生长发育。该研究采用喷施硝酸铵(NH4NO3)模拟氮沉降,分析了不同浓度氮沉降作用下紫苏叶中紫苏醛、D-柠檬烯、α-蒎烯等3种挥发油成分的变化规律。结果表明:随喷施氮盐浓度不断提高,紫苏叶挥发油的3种主要成分含量均有显著下降趋势;氮盐浓度升至0.044 mol·L~-1时,紫苏醛、D-柠檬烯、α-蒎烯的含量降至最低,之后趋于稳定;氮盐浓度对3种挥发油成分含量的比例也有影响;不同氮盐浓度处理下,3种挥发油成分的变异系数不同,紫苏醛的变异系数为0.692 9,D-柠檬烯的变异系数为0.460 1,而α-蒎烯的变异系数为0.271 6,即紫苏醛含量变化最大,α-蒎烯含量最为稳定。大气氮沉降浓度对紫苏叶挥发油主要成分含量有显著影响,随氮盐浓度不断提高,紫苏醛、D-柠檬烯、α-蒎烯等3种挥发油成分含量呈降低趋势,尤以紫苏醛含量的降低最为剧烈。氮沉降增加对紫苏叶有效成分含量有降低的作用。  相似文献   

7.
紫苏 (FRUITFULL,FUL)基因属植物MADS-box家族中的AP1/FUL亚家族,具有调控开花时间、花分生组织分化和果实发育的功能。本研究根据紫苏转录物组注释克隆获得PfFUL基因序列,利用生物信息学方法对PfFUL蛋白的基本理化性质进行了分析,通过系统发育树分析了PfFUL与其他物种FUL的进化关系。构建35S::PfFUL植物表达载体,分别转化野生型Col-0及突变体ful-7拟南芥获得了过表达35S::PfFUL/Col-0和回补突变35S::PfFUL /ful-7植株,并对其进行表型比较分析,初步明确了PfFUL基因在植株开花及角果发育过程中的功能。PfFUL基因全长CDS为738 bp,编码245个氨基酸。系统发育分析表明,紫苏PfFUL与番茄、一串红和芡欧鼠尾草亲缘关系较近,而与拟南芥、烟草和葡萄关系较远。相比于Col-0和ful-7,转基因植株均表现出早花现象(P<0. 05),35S::PfFUL /ful-7植株的角果长度可恢复到野生型表型(P>0. 05),且种子皱缩的数量明显降低(P<0. 01)。此外,表型观察发现,转基因植株还表现出节间生长伸长,茎生叶变窄且卷曲。本研究证实,PfFUL基因可调控植物开花和角果的发育,并参与营养生长。  相似文献   

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Perilla frutescens (Lamiaceae) is an important herbal plant with hundreds of bioactive chemicals, among which perillaldehyde and rosmarinic acid are the two major bioactive compounds in the plant. The leaves of red perilla are used as traditional Kampo medicine or food ingredients. However, the medicinal and nutritional uses of this plant could be improved by enhancing the production of valuable metabolites through the manipulation of key enzymes or regulatory genes using genome editing technology. Here, we generated a high-quality genome assembly of red perilla domesticated in Japan. A near-complete chromosome-level assembly of P. frutescens was generated contigs with N50 of 41.5 Mb from PacBio HiFi reads. 99.2% of the assembly was anchored into 20 pseudochromosomes, among which seven pseudochromosomes consisted of one contig, while the rest consisted of less than six contigs. Gene annotation and prediction of the sequences successfully predicted 86,258 gene models, including 76,825 protein-coding genes. Further analysis showed that potential targets of genome editing for the engineering of anthocyanin pathways in P. frutescens are located on the late-stage pathways. Overall, our genome assembly could serve as a valuable reference for selecting target genes for genome editing of P. frutescens.  相似文献   

9.
Two novel antioxidants (vinyl caffeate and trans-p-menth-8-en-7-yl caffeate) and seven known antioxidants (3,4-dihydroxybenzaldehyde, methyl 3,4-dihydroxy-benzoate, methyl caffeate, 3′,4′,5,7-tetra-hydroxy-flavone, caffeic acid, 6,7-dihydroxycoumarin, and rosmarinic acid) were isolated from Perilla frutescens Britton var. crispa (Thunb.). The redox potentials of the novel isolated antioxidative compounds were comparable to those of known antioxidants. trans-p-menth-8-en-7-yl caffeate was effective to prevent the oxidative degradation of perillaldehyde in the essential oil of P. frutescens.  相似文献   

10.
不同基因型紫苏耐盐性比较研究   总被引:2,自引:1,他引:2  
以不同基因型紫苏为材料,研究150 mmol/L NaCl胁迫对紫苏种子萌发,幼苗生长及其生理指标的影响.结果显示:(1)盐胁迫下,不同基因型紫苏种子发芽率和发芽势均比对照显著降低,种子发芽指数、活力指数等发芽指标下降;不同基因型紫苏幼苗地上部和地下部干重均有不同程度降低,高油1(Y1)、紫野1(Z1)、紫野2(Z2)、紫野3(Z3)和紫野4(Z4)幼苗组织含水量均比对照显著降低,且幼苗存活率低而盐害指数显著高于其他基因型品种.(2)盐胁迫下不同基因型紫苏幼苗根系活力均比对照显著降低,其中Y1降幅最大,紫野6(Z6)和紫野7(Z7)降幅较小,可溶性糖含量均比对照显著提高.基因型Y1、Z1和Z2幼苗中MDA含量显著高于对照,表明其膜脂过氧化程度较高.(3)基因型苏引1(S1)、Z6、Z7、紫野8(Z8)、紫野9旱(ZY9)和紫野10(Z10)幼苗叶片中SOD、CAT和POD活性均显著高于对照,Y1、Z1、Z2、Z3和Z4幼苗中SOD和CAT活性与对照差异不显著,且Y1、Z2和Z4幼苗POD活性较对照显著降低,表明其抗氧化能力较差.研究发现,基因型S1、Z6和Z7在盐胁迫下其种子发芽能力、耐盐能力及幼苗渗透调节能力和活性氧清除能力均较强,表现出较强的耐盐性;基因型Y1、Z1、Z2、Z3和Z4受盐胁迫影响较大,为盐敏感基因型;Z8、Z9、ZY9和Z10为中等耐盐性基因型.  相似文献   

11.
    
Vascular dementia (VaD) is characterized by a time-dependent memory deficit and essentially combined with evidence of neuroinflammation. Thus, polyphenol-rich natural plants, which possess anti-inflammatory properties, have received much scientific attention. This study investigated whether Perilla frutescens leaf extract (PFL) exerts therapeutic efficacy against VaD. Sprague Dawley rats were divided into five groups: SO, sham-operated and vehicle treatment; OP, operated and vehicle treatment; PFL-L, operated and low-dose (30 mg/kg) PFL treatment; PFL-M, operated and medium-dose (60 mg/kg) PFL treatment; and PFL-H, operated and high-dose (90 mg/kg) PFL treatment. Two-vessel occlusion and hypovolemia (2VO/H) were employed as a surgical model of VaD, and PFL was given orally perioperatively for 23 days. The rats underwent the Y-maze, Barnes maze, and passive avoidance tests and their brains were subjected to histologic studies. The OP group showed VaD-associated memory deficits, hippocampal neuronal death, and microglial activation; however, the PFL-treated groups showed significant attenuations in all of the above parameters. Using lipopolysaccharide (LPS)-stimulated BV-2 cells, a murine microglial cell line, we measured PFL-mediated changes on the production of nitric oxide (NO), TNF-α, and IL-6, and the activities of their upstream MAP kinases (MAPKs)/NFκB/inducible NO synthase (iNOS). The LPS-induced upregulations of NO, TNF-α, and IL-6 production and MAPKs/NFκB/iNOS activities were globally and significantly reversed by 12-h pretreatment of PFL. This suggests that PFL can counteract VaD-associated structural and functional deterioration through the attenuation of neuroinflammation.  相似文献   

12.
紫苏花蜜腺的发育解剖学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
紫苏花蜜腺位于不均等分裂的花盘裂片上,属于子房基部的盘状蜜腺。3枚小裂片上的蜜腺由分泌表皮和产蜜组织组成,而另一枚大裂片上的指状蜜腺则由分泌表皮、产蜜组织和维管束组成。4枚蜜腺的表皮细胞外均具薄的角质层,仅在指状蜜腺的顶部分布着密集的气孔器。蜜腺来源于花盘表面的2~3层细胞。在蜜腺发育过程中,液泡和淀粉粒呈现有规律的消长变化,这与蜜汁的合成与分泌有关。3枚小裂片蜜腺的原蜜汁来源和泌蜜途径与指状蜜腺不同。  相似文献   

13.
紫苏愈伤组织迷迭香酸的纯化及抗菌活性研究   总被引:26,自引:0,他引:26  
紫苏叶外植体在添加NAA和2,4-D的MS培养基上诱导分化愈伤组织,愈伤组织中迷迭香酸的含量为85%,愈伤组织干燥后经乙醇提取,乙酸乙酯萃取后,经Sephadex LH-20柱层析,最后获得了纯度为95%的迷迭香酸。抑菌实验表明此法获得的迷迭香酸对大肠杆菌、金黄色葡萄球菌及立枯丝合菌的生长均有明显的抑制作用,其最低抑制浓度分别为300、400及800μg/mL。  相似文献   

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紫苏腺毛的形态发生研究   总被引:4,自引:0,他引:4  
紫苏叶上有两种腺毛:质状腺毛和头状腺毛。两者都具1个基细胞、1个柄细胞和头部。前者的头部可由1、2、4或8个分泌细胞组成,扩展成质状;后者的头部由1、2或4个分泌细胞组成,聚成圆球状。两种腺毛的原始细胞都来源于原表皮细胞,经两次平周分裂产生基细胞、柄细胞和顶细胞。在腺毛后期的形态发生中,柄细胞的分化状态决定腺毛的类型。若柄细胞保持扁平关且处于分生状态时,其顶细胞将发育成质状腺毛的头部;若柄细胞纵向  相似文献   

18.
紫苏叶上有两种腺毛:盾状腺毛和头状腺毛。两者都具1个基细胞、1个柄细胞和头部。前者的头部可由1、2、4或8个分泌细胞组成,扩展成盾状;后者的头部由1、2或4个分泌细胞组成,聚成圆球状。两种腺毛的原始细胞都来源于原表皮细胞,经两次平周分裂产生基细胞、柄细胞和顶细胞。在腺毛后期的形态发生中,柄细胞的分化状态决定腺毛的类型。若柄细胞保持扁平状且处于分生状态时,其顶细胞将发育成盾状腺毛的头部;若柄细胞纵向引长并迅速液泡化时,其顶细胞将发育成头状腺毛的头部。  相似文献   

19.
    
The sweetpotato whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae), is a major pest on greenhouse crops including sweet pepper (Capsicum annuum L.), which is one of the leading greenhouse crops in South Korea. Synthetic insecticides, especially the neonicotinoids, have been used to conventionally control this pest. There have been continuous efforts to develop plant‐derived compounds as insecticides, deterrents, and repellents to reduce spraying synthetic insecticides. To develop new plant‐extract insecticides, we investigated the insecticidal effects of Perilla sp. (Perilla frutescens var. crispa) extract on B. tabaci in laboratory conditions. The Perilla sp. extract induced 90 % mortality within one hour, but phytotoxicity symptoms on sweet pepper leaves were also observed. We monitored the population change and spatial distribution of adult B. tabaci in an experimental sweet pepper greenhouse using yellow sticky traps, and analyzed distribution patterns by spatial analysis with distance indices (SADIE). Based on monitoring data and SADIE analysis, we concluded that B. tabaci aggregated near the greenhouse entrances, and it showed aggregation and association pattern as time passed. Therefore, we recommend spraying Perilla sp. extract near the entrances or wild host before the pest population penetrates. It will be one of the alternative pest management strategies to reduce B. tabaci population with fewer negative effects from chemical insecticide. Further study is required to reduce the phytotoxicity symptoms from Perilla sp. extract spray and insecticidal effect should be evaluated under field conditions.  相似文献   

20.
郭凤根  王仕玉 《植物研究》2000,20(3):270-274
选取26个性状,应用不加权算术平均配对法对来自云南各地的20份紫苏试材进行了数值分类学研究。结果表明:这20份紫苏试材可分成紫苏、回回苏、耳齿紫苏、野生紫苏和白苏5个变种;并对白苏变种的设立和耳齿紫苏变种的分布进行了探讨。  相似文献   

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