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排序方式: 共有311条查询结果,搜索用时 31 毫秒
11.
Iris adriatica Trinajsti? ex Miti? (Iridaceae L.) is a strictly endemic taxon from Croatia. It is a rhizomatous dwarf plant from the I. pumila complex with a distribution area limited to the Croatian part of the Mediterranean area, mainly central Dalmatia. The genus Iris is known for its richness in isoflavonoids which also play a significant role in chemotaxonomy and biological activity. Hence, in the current study, different plant batches of I. adriatica collected in early spring of 2016 were analysed for their phytochemical profiles and qualitatively compared. UHPLC-PDA-ESI-MS analyses of methanolic rhizome extracts were performed. Altogether, 36 compounds, representing isoflavonoids (including 6,7-methylendioxy derivatives), benzophenones and xanthones were found as aglycones or in glycosidically bound form to be the main constituent groups of I. adriatica rhizomes. Qualitative results were identical between different batches of plant material from collection sites in central Dalmatia, they differed only in quantity. For some phenolic compounds of I. adriatica, chemotaxonomic relevance was detected.  相似文献   
12.
Abstract

Increased nitrogen and phosphorus pollution causes eutrophication in water bodies. Using aquatic plants to remove nutrients from water is an attractive phytoremediation. It is a cost-effective, environment-friendly, and efficient way that reduces water body eutrophication by the plant. It is important to choose suitable macrophytes to remove excess N and P under different nutrient conditions. In this study, six macrophyte species (Polygonum orientale, Juncus effuses, Iris pseudocorus, Phragmites australis, Iris sanguinea, Typha orientalis) were tested. Simulation experiment was conducted under five N and P levels. The removal rate, relative growth rate, and the dynamic nutrition concentration of cultivated solution were investigated. Of all the treatment, a 23–95% reduction in N removal and a 29–92% reduction in P removal were recorded. The results showed I. sanguinea is a promising species to treat various eutrophic waters and the other five species can be used specifically to treat certain types of water. The data provided a theoretical guidance to plant species selection for phytoremediation of polluted water bodies for the purpose of water quality improvement around the different reservoir in northern China.  相似文献   
13.
This study was aimed at investigating the phytochemical composition and antioxidant capacity of rhizomes, above‐ground vegetative parts and flowers of three Iris species: Iris humilis Georgi , Iris pumila L. and Iris variegata L. UHPLC‐Orbitrap MS analysis was used for determination of phytochemical profile. Total pigments, phenolics, flavonoids, soluble sugars and starch content as well as ABTS antioxidant capacity were also determined. In total, 52 phenolics compounds were identified with 9 compounds (derivatives of iriflophenone, apigenin C‐glycosides, luteolin O‐glycoside, isoflavones derivatives of iristectorigenin, dichotomitin, nigracin and irilone) never reported before in Iris spp. Differences in phenolic composition profile, pigments, soluble sugar, starch, total phenolics and flavonoids content and total antioxidant capacity were found among Iris species and different part of plants. Significant correlation between total phenolic content and antioxidant capacity was determined. The obtained results are comparable with those obtained for medical plants. These findings could be useful for fingerprinting characterization of Iris species and estimation of possible use in pharmaceutical industries.  相似文献   
14.
Iris pseudacorus L. has been widely used in aquatic ecosystem to remove nutrient and has achieved positive effects. However, little is known regarding the nutrient-removal performance and physiological responses of I. pseudacorus for brackish eutrophic water treatment due to high nutrients combined with certain salinity levels. In this study, I. pseudacorus-planted microcosms were established to evaluate the capacity of I. pseudacorus to remove excessive nutrients from fresh (salinity 0.05%) and brackish (salinity 0.5%) eutrophic waters. The degradation of total nitrogen and ammonia nitrogen were not affected by 0.5% salinity; 0.5% salinity promoted the degradation of nitrate nitrogen while severely inhibited the degradation of total phosphorus. Additionally, 0.5% salinity was found to induce stress responses quantified by measuring six physiological indexes. Compared to 0.05% salinity, 0.5% salinity resulted in significant decreases in the chlorophyll a, b and total chlorophyll contents of I. pseudacorus which closely related to photosynthesis (p < 0.05). Furthermore, the higher proline, malondialdehyde contents and antioxidant enzyme activities were detected in I. pseudacorus exposed to 0.5% salinity, which provided protection against reactive oxygen species. The results highlight that the cellular stress assays are efficient for monitoring the health of I. pseudacorus in salinity shock-associated constructed wetlands.  相似文献   
15.
采用土壤栽培方法,研究了在Cu添加量为0(CK)、200、400、600、800和1 000μg·g-1的土壤中溪荪(Iris sanguinea Donn es Horn.)和花菖蒲(I.ensata Thunb.var.hortensis Makino et Nemoto)叶和根的数量、长度及生物量(干质量)6个生长指标的变化趋势,并对叶和根中的Cu含量和积累量、全株的Cu积累量、Cu的富集系数及转运系数进行了比较分析.结果表明:随土壤中Cu添加量的提高,溪荪的根数逐渐降低且显著低于对照;而溪荪的其余5个生长指标和花菖蒲的6个生长指标均总体呈现出在Cu添加量较低的条件下逐渐增加并显著高于对照、在Cu添加量较高的条件下逐渐减小且显著小于对照的变化趋势;其中在Cu添加量1 000μg·g-1的土壤中2种植物的生长均受到显著抑制(P<0.05);而添加400和600μg·g-1Cu则分别对2种植物的生长有一定的促进作用.随土壤中Cu添加量的增加,溪荪和花菖蒲叶及根中的Cu含量均逐渐提高;溪荪对Cu的富集系数和转运系数以及花菖蒲对Cu的富集系数均显著小于对照,而花菖蒲对Cu的转运系数则呈现在Cu添加量较低的条件下高于对照、Cu添加量较高的条件下低于对照并逐渐减小的趋势;在添加了Cu的土壤中,溪荪叶、根和全株对Cu的积累量均低于花菖蒲,但均显著高于对照,且2种植物根的Cu含量及积累量均大于叶片,表明溪荪和花菖蒲均具有一定的Cu积累能力,且主要积累在根中,花菖蒲对Cu的积累能力优于溪荪.综合分析结果显示:溪荪和花菖蒲不是Cu超积累植物,但对Cu胁迫均具有一定的耐性,且花菖蒲的耐性略强于溪荪;溪荪和花菖蒲分别适宜栽植于Cu含量400和600μg·g-1以下的土壤中,可用于轻度和中度Cu污染土壤的植物修复和环境美化.  相似文献   
16.
德国小蠊(Blattella germanica)是一种重要的室内卫生害虫,化学防治是目前主要的防治手段,但抗药性已逐渐成为制约德国小蠊防治的关键因素。德国小蠊抗药性的产生存在多种机理,本文从行为抗性、表皮穿透性降低、代谢抗性、靶标抗性及微生物降解等方面对德国小蠊抗药性产生机理进行了综述,重点阐述了近年来德国小蠊抗药性机理最新的研究进展。  相似文献   
17.
To better understand what directs and limits the evolution of phenotype, constraints in the realization of the optimal phenotype need to be addressed. That includes estimations of variability of adaptively important traits as well as their correlation structures, but also evaluation of how they are affected by relevant environmental conditions and development phases. The aims of this study were to analyze phenotypic plasticity, genetic variability and correlation structures of important Iris pumila leaf traits in different light environments and ontogenetic phases, and estimate its evolutionary potential. Stomatal density, specific leaf area, total chlorophyll concentration and chlorophyll a/b ratio were analyzed on I. pumila full‐sib families in the seedling phase and on the same plants after 3 years of growth in contrasting light conditions typical for ontogenetic stage in question. There was a significant phenotypic plasticity in both ontogenetic stages, but significant genetic variability was detected only for chlorophyll concentrations. Correlations of the same trait between different stages were weak due to changes in environmental conditions and difference in ontogenetic reaction norms of different genotypes. Ontogenetic variability of correlation structures was detected, where correlations and integration were higher in seedlings compared with adult plants 3 years later. Correlations were affected by environmental conditions, with integration being higher in the lower light conditions, but correlations between phases being stronger in the higher light treatment. These findings demonstrated that the analyzed traits can be selected and can mostly evolve independently in different environments and ontogenetic stages, with low genetic variability as a potentially main constraint.  相似文献   
18.
Wastewater from different sources shows great differences in concentrations and ratios of N and P. In order to choose suitable plant species to remove excess N and/or P from polluted waters, it is important to know the performances of these plants under different N and P concentrations. In this study, we investigated the growth and N and P removal rate of three macrophytes, Coix lacryma-jobi, Iris wilsonii, and Arundo donax under six N and P combination treatments. C. lacryma-jobi preferred higher N and P concentrations (16 mg N L?1 and 3.2 mg P L?1), and increasing N supply could increase its P removal rate. I. wilsonii exhibited a growth preference at a combination of moderate N and P concentrations (8 mg N L?1 and 0.8 mg P L?1). A. donax could grow well at all combinations of N and P and had significantly higher relative growth rate and N and P removal rates than the other two species. These results showed A. donax is a promising species to treat various polluted waters and the other two species can be used specifically to treat certain types of wastewater.  相似文献   
19.
长白山区鸢尾属植物资源及其开发利用   总被引:6,自引:0,他引:6  
对长白山鸢尾属植物的种类、分布、储量、生境、鉴别及开发利用等方面做了评细地调查研究,为开发长白山区鸢尾属植物资源提供了科学依据。  相似文献   
20.
采用液体培养法研究了0(CK)、200、400、600和800 mg·L-1Pb胁迫条件下路易斯安那鸢尾(Louisiana Iris)品种‘Professor Neil’幼苗生长,叶片叶绿素含量,叶片和根系的丙二醛(MDA)和脯氨酸(Pro)含量、超氧阴离子自由基(O-·2)产生速率以及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性的变化。结果表明:随Pb质量浓度的提高,幼苗的株高、根长、叶片和根系干质量以及耐性指数总体呈逐渐下降的趋势,且总体上显著低于对照(P〈0.05),但各处理组间差异不显著。幼苗叶片的叶绿素a和b含量均随Pb质量浓度提高而缓慢下降,但仅在800 mg·L-1Pb胁迫条件下叶绿素a含量显著低于对照(P〈0.05),其余处理组的叶绿素a和b含量及叶绿素a/b比值均与对照无显著差异。叶片和根系的MDA和Pro含量及POD活性均随Pb质量浓度提高逐渐增加,根系的SOD活性则随Pb质量浓度提高逐渐降低;而叶片的SOD活性以及叶片和根系的CAT活性和O-·2产生速率均在200~600 mg·L-1Pb胁迫条件下随Pb质量浓度提高逐渐增加,但在800 mg·L-1Pb胁迫下均不同程度降低,表明路易斯安那鸢尾可通过体内抗氧化酶和相关物质的诱导及合成缓解低浓度Pb胁迫对其造成的毒害作用,而高浓度Pb胁迫对路易斯安那鸢尾的伤害较重。综合分析结果表明:路易斯安那鸢尾具有一定的耐Pb特性和修复Pb污染水体的潜能。  相似文献   
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