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排序方式: 共有125条查询结果,搜索用时 750 毫秒
111.
灰叶堇菜(Viola delavayi Franch.)属堇菜科(Violaceae)堇菜属(Viola L.)植物,全草入药,治肺炎,根治虚弱、头晕、风湿关节炎、小儿疳积、跌打损伤,主要分布在云南昆明等地.随着人们的物质生活越来越丰富,膳食文化开始注重绿色食品,强调回归自然,中医和膳食工作者开始注意食疗法的挖掘和研究.灰叶堇菜具有食疗的价值,在云南的一些地区将它作为膳食.灰叶堇菜的营养成分的分析未见报道.本文对灰叶堇菜的营养成分进行了测定,以期为该种的开发利用提供科学依据. 相似文献
112.
B. Stevanović G. Dražić J. Šinžar‐Sekulić Lj. Melovski I. Novović 《Plant biosystems》2013,147(3):644-655
Abstract The uptake and distribution of arsenic (As) and some heavy metals was determined in three Viola endemic species from As‐overloaded soil in an abandoned mine at Alchar, Republic of Macedonia (FYROM – The Former Yugoslav Republic of Macedonia). Some essential elements were also analyzed in order to characterize the common geochemical properties of this site. Total As content in soil ranged from 3347 to 14,467 mg kg?1, and plant available As from 23 to 1589 mg kg?1. The concentration of As in roots ranged from 783 mg kg?1 in Viola macedonica to 2124 mg kg?1 in Viola arsenica. Only a small amount of As accumulated in the aboveground parts of these species (<100 mg kg?1), while in shoots of Viola allchariensis, As accumulated in the range 187–439 mg kg?1. Arsenic accumulation in the roots of these Viola species may make these plants valuable tools for the bioindication and phytoremediation (phytostabilization) of As in naturally loaded and anthropogenically contaminated soils. 相似文献
113.
Hirokazu Matsui Seiya Chiba Tokuji Shimomura 《Bioscience, biotechnology, and biochemistry》2013,77(5):841-847
An active β-amylase was purified from germinated rice seeds by precipitation with ammonium sulfate, acid treatment, chromatographies on DEAE-cellulose and DEAE-Sephadex A-50, and gel filiations on Sephadex G-75. The purified enzyme was homogeneous in disc electrophoretic analysis.The molecular weight was estimated to be approximately 53,000 by thin-layer gel filtration and polyacrylamide gel electrophoresis. The isoelectric point was found to be pH 5.0 by disc electrofocusing.The optimum pH was found to be in the pH range of 5.5 to 6.5. The Km value for soluble starch was 3 mg/ml. The enzyme was inhibited by sulfhydryl reagents or heavy metal ions.The active β-amylase was oxidatively dimerized by treatment with 0.3 m ferricyanide in 3 m urea. The dimerized enzyme was thought to be one of inert β-amylases in ungerminated rice seeds. 相似文献
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A protocol for in vitro propagation was developed for Viola pilosa, a plant of immense medicinal value. To start with in vitro propagation, the sterilized explants (buds) were cultured on MS basal medium supplemented with various concentrations of growth regulators. One of the medium compositions MS basal + 0.5 mg/l BA + 0.5 mg/l TDZ + 0.5 mg/l GA3 gave best results for in vitro shoot bud establishment. Although the problem of shoot vitrification occurred on this medium but this was overcome by transferring the vitrified shoots on MS medium supplemented with 1 mg/l BA and 0.25 mg/l Kn. The same medium was found to be the best medium for further in vitro shoot multiplication. 100 % root induction from in vitro grown shoots was obtained on half strength MS medium supplemented with 1 mg/l IBA. In vitro formed plantlets were hardened and transferred to soil with 83 % survival. Additionally, conservation of in vitro multiplying shoots was also attempted using two different approaches namely slowing down the growth at low temperature and cryopreservation following vitrification. At low temperature retrieval rate was better at 10 °C than at 4 °C after conservation of in vitro multiplying shoots. In cryopreservation–vitrification studies, the vitrified shoot buds gave maximum retrieval of 41.66 % when they were precooled at 4 °C, while only 16.66 % vitrified shoots were retrieved from those precooled at 10 °C. Genetic stability of the in vitro grown plants was analysed by RAPD and ISSR markers which indicated no somaclonal variation among in vitro grown plants demonstrating the feasibility of using the protocol without any adverse genetical effects. 相似文献
117.
为探讨叶片斑纹的光合适应意义,该文选择有斑和无斑两种叶型的维西堇菜(Viola monbeigii)作为研究材料,采用石蜡切片制片和显微镜观察叶片结构及GFS 3000便携式光合测量仪测量光合参数并进行比较。结果表明:(1)两种叶型维西堇菜气孔均为不等型气孔,有斑叶片上、下表皮气孔密度、栅栏组织(PT)厚度、栅栏组织与海绵组织的比值(PT/ST)均显著低于无斑叶片; 而上表皮气孔较大,表现出更适应弱光环境的结构特征。(2)两种叶型维西堇菜暗呼吸速率(Rd)、初始荧光(Fo)、最大荧光产量(Fm)、光化学猝灭系数(qP)、非光化学猝灭系数(qN)、PSⅡ最大光化学量子产量(Fv/Fm)、实际光化学反应量子效率(Yield)均无显著差异,有斑植株叶片叶绿素含量、最大净光合速率(Pmax)显著低于无斑植株; 有斑叶片表观光合电子传递速率(ETR)在光合有效辐射(PAR)处于400~2 000 μmol·m-2·s-1之间时显著低于无斑叶片,无斑植株的光饱和点(LSP)高于有斑植株,而补偿点(LCP)较低。综上认为,无斑植株PAR利用范围较宽,光合适应能力更强,有利于维西堇菜充分利用环境中有限的资源,保障物种生存; 有斑植株具有较适应弱光胁迫的特征,表明叶片斑纹的出现可能是维西堇菜适应林缘弱光环境的一种策略。 相似文献
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Reproductive ecology of Viola mirabilis var. subglabra representing intermediate flowering characteristics between stemless and stemmed Viola
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Yoshinori Shinohara Hiroki Yamagishi Masato Hayamizu Ohjiro Onishi Masashi Ohara 《Plant Species Biology》2017,32(4):432-439
Viola (Violaceae) is one of the largest genera in angiosperms. This genus is essentially classified into stemless and stemmed groups based on growth morphology. However, Viola mirabilis var. subglabra is an exception in having intermediate flowering characteristics; cleistogamous (CL) flowers are formed in the axils of stem leaves, whereas chasmogamous (CH) flowers arise from basal rosettes (radical CH (CH(r)) flowers) and also in the axils of the stem (axially CH (CH(a)) flowers). To understand why the pattern of flower production varies in this Viola species, flower production was investigated in 10 Japanese populations from Hokkaido to the western part of Honshu in 2014 and 2015. Furthermore, flower characteristics were also compared between CH(r) and CH(a) flowers in Hokkaido. In this species, the production of CH flowers varied among individuals, and they were categorized into three groups, individuals that produced (i) only CH(r) flowers, (ii) only CH(a) flowers and (iii) both CH flowers. The frequency of these groups differed among populations, but some individuals changed the category between 2014 and 2015. Thus, the production of CH(r) and CH(a) flowers plastically changes depending on individual conditions and/or environmental factors. On the other hand, CH(r) and CH(a) flowers differed in flower size and flowering phenology. These results suggest that two types of CH flowers may play different roles in reproduction in each population, but fruit sets and seed sets did not differ between two types of CH flowers. 相似文献
120.
Mycocentrospora acerina (Hartig) Deighton can kill or suppress the growth of Viola arvensis (Murr.) in spring wheat in pot-grown plants in both glasshouse and outdoor studies. The level of damage to V. arvensis and the effect on its competition with wheat were affected by inoculum density and environmental conditions. High inoculum density (105 macroconidia/ml) caused high mortality in V. arvensis and eliminated its competitive effect on wheat. At a lower density (104 macroconidia/ml), the V. arvensis fresh weight and its competition with the wheat were suppressed by up to 38 and 28% respectively, depending on environmental conditions. 相似文献