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51.
Yanqing Wu  Jiao Liu  Daqiu Zhao  Jun Tao 《Phyton》2022,91(9):2017-2032
Herbaceous peony (Paeonia lactiflora Pall.) is an important ornamental plant worldwide. In its natural state, P. lactiflora often manifests traits like rapidly elongating internodal growth, loose plant types, and soft inflorescence stems. However, very little has been known about the measures for controlling these traits. This study investigated the effect of applying paclobutrazol (PBZ) on the plant growth and flower quality in P. lactiflora. The results indicated that PBZ application reduced the plant height (8.05%), plant crown width (14.72%), and leaf area (10.90%), but increased the leaf thickness (18.18%) and stem diameter (over 11%) in P. lactiflora. Meanwhile, PBZ application was also found to increase the chlorophyll (Chl) a (29.63%), Chl b (33.33%), Chl a+b (30.56%), SPAD (27.32%), relative water content (0.47%), soluble sugar (5.09%) and activities of three antioxidant enzymes (superoxide dismutase 169.66%, peroxidase 3.59%, catalase 319.30%), but decreased the relative electrical conductivity (18.52%). Additionally, the application of PBZ was found to affect the flowering quality of P. lactiflora, increasing the flower diameter and fresh weight only in the flower-bud stage. This initiates the bloom stage, where there was a decrease in the total content of the aromatic compounds except for the flower-bud stage, and faded the flower color by reducing the content of anthocyanin. These results demonstrated that the application of PBZ can regulate the P. lactiflora plant types with no significant decrease in its ornamental values. This might provide a theoretical basis for further applying PBZ in P. lactiflora for use in urban landscape spaces.  相似文献   
52.
A comparison of in vitro with in vivo flowering in Gentian   总被引:1,自引:0,他引:1  
Young nodal explants of Gentiana triflora Pall. var. axillariflora were cultured in a woody plant medium (WPM) supplemented with B5 vitamins, sucrose (3%) and kinetin (2.0 μM). A novel observation was made in that in vitro flowering occurred following development of the axillary bud of the cultures. A comparison was made between in vitro and in vivo flowers. Although smaller in size, the in vitro flowers were morphologically comparable to the in vivo ones. Flowers from both sources were semi-opened or not opened. The colour of the in vitro flowers was paler than those in vivo. Stigma development was generally poor in both in vitro and in vivo flowers. Pollen viability was over 90% in both types of flowers. About 11% and 34% of pollen from in vitro and in vivo flowers, respectively, germinated on WPM containing 100 g l−1 sucrose solidified with 10 g l−1 agar. Hand pollination of stigma could raise viable seed production in in vivo-flowering plants from 0.3 o/o (i.e. without aided pollination) to 3% but none in in vitro-flowering plants where only seed-like structures, probably unfertilised ovules, were found. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
53.
通过野外标本采集、鉴定和对国内标本馆大量标本的观察研究,在国内文献中首次报道了科布尔黄耆(As-tragalus koburensis Bunge);纠正了之前国内几个标本馆将科布尔黄耆鉴定为乳白花黄耆(A.galactites Pall.)的错误;同时将宁夏黄耆(A.ningxiaensis Podlech et L.R.Xu)处理为科布尔黄耆的一个异名;并对科布尔黄耆在中国的分布范围和生态地理特征进行了讨论。  相似文献   
54.
ABSTRACT: BACKGROUND: The root bark of Paeonia suffruticosa Andrews (PSE), also known as Moutan Cortex, has been widely used in Asia to treat various diseases. The molecular mechanisms by which PSE exerts its anti-oxidant and anti-inflammatory activities are well known, but its anti-cancer activity is not yet well understood. Here, we present evidence demonstrating that PSE can be used as a potent anti-cancer agent to treat gastric cancer. METHODS: The effects of the ethanol extract of PSE on cell proliferation were determined using an MTT (1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan) assay. Cell cytotoxicity induced by the PSE extact is measured using an LDH leakage assay. Flow cytometry was used to analyze the cell cycle and to measure the subG0/G1 apoptotic cell fraction. Apoptosis induced by the PSE extact is also examined using a DNA fragmentation assay. Western blot analysis is used to measure the levels of apoptotic proteins such as Fas receptor, caspase-8, caspase-3, PARP, Bax, Bcl-2, MDM2, and p53. RESULTS: This study demonstrated that treating AGS cells with the PSE extact significantly inhibited cell proliferation and induced cytotoxicity in a dose- and time-dependent manner. The PSE extract also induced apoptosis in AGS cells, as measured by flow cytometry and a DNA fragmentation assay. We found that the PSE extract induced apoptosis via the extrinsic Fas-mediated apoptosis pathway, which was concurrent with the activation of caspases, including caspase-8 and caspase-3, and cleavage of PARP. The MDM2-p53 pathway also played a role in the apoptosis of AGS cells that was induced by the PSE extract. CONCLUSIONS: These results clearly demonstrate that the PSE extact displays growth-suppressive activity and induces apoptosis in AGS cells. Our data suggest that the PSE extact might be a potential anti-cancer agent for gastric cancer.  相似文献   
55.
报道了Paeonia anomala L.的核型,澄清了新疆阿尔泰地区分布的该物种的染色体数目。分布于该地区的Paeonia anomala L.的核型组成:2n=2x=10=6m+2sm+2st。该类群核型与该属其它类群一致——2A型。在综合比较分析该属染色体参数以及核型不均一性参数,包括最长,最短染色体比(L1/Ln)和染色体不对称系数(CKOA)的基础上,我们发现该属三个组在核型上没有明显分化,仅在木本类群(Sect.Mouton DC.)和草本类群(Sect.Onaepia Lindley和Sect.Paeonia)之间存在微小差异。此外,作为二倍体类群,新疆阿尔泰地区分布的Paeonia anomala L.很可能是二倍体杂种,这将为研究被子植物的父母本同倍化杂交式物种起源提供一个很好的研究材料。  相似文献   
56.
Paeoniflorin is one of the bioactive ingredients of the roots of Paeonia lactiflora (Paeoniaceae). A comparative study of processed and non-processed commercial samples of dried roots of P. lactiflora indicated a very low level of paeoniflorin in the processed sample and the formation of a new more polar component, sodium paeoniflorin sulphonate, during treatment of the roots with sulphiting agents.  相似文献   
57.
伍晨曦  孙羽  冯固 《生态学报》2009,29(4):1849-1858
为了理解荒漠短命植物小车前(Plantago minuta Pall.)种子表面的粘液物质对种子在干旱环境中萌发的作用,在室内控制条件下研究了粘液物质的吸水保水特性、剥离粘液物质的种子(无粘液种子)和保留粘液物质的种子(粘液种子)在-1.15~-0.15 MPa不同渗透胁迫条件下的萌发状况.结果表明: (1)小车前种子表面的粘液物质干重占粘液种子干重的5.6%;在去离子水中,粘液物质可以吸收相当于其自身干重217.1倍的水分;粘液物质的存在使得小车前种子的吸水倍数由2倍增加至14倍,从而保证为种子萌发提供充足的水分;(2)干燥的粘液种子吸水2h后即达到饱和,而吸水饱和后的粘液种子在室温下晾置,经过48h后又干燥失水恢复至原重;(3)在去离子水中或低渗透胁迫(-0.33~-0.15 MPa) 条件下,粘液物质吸水作用能促进小车前种子萌发,粘液种子3d的发芽势和10d的总萌发率均显著高于无粘液种子;在高渗透胁迫(-1.15~-0.73MPa)条件下,粘液种子3d的发芽势显著低于无粘液种子的,而10d的总萌发率与无粘液种子的没有显著差别,表明粘液物质在干旱条件下可能从种子而非外界环境中吸取水分,减缓了种子萌发速率.通过上述结果可以认为小车前种子表面的粘液物质在早春干湿交替剧烈的荒漠生境中起到通过调节水分来调节种子萌发的作用,这种萌发策略大大降低了因大批种子同时萌发导致幼苗受旱甚至种群灭亡的潜在风险.  相似文献   
58.
L.L. Pan  M. Dai   《Phytomedicine》2009,16(11):1027-1032
Paeonol (2′-hydroxy-4′-methoxyacetophenone), the main active compound of the radix of Paeonia suffruticosa, has been reported to have a beneficial effect in prevention and treatment of cardiovascular diseases. Vascular cell adhesion molecule-1 (VCAM-1), plays a crucial role in case of early inflammatory responses, including atherosclerosis. In this study, we investigated the effect of paeonol on TNF-α-induced VCAM-1 expression in rat aortic endothelial cells (RAECs). The VCAM-1 expression in paeonol treated RAECs was measured. Paeonol inhibited TNF-α-induced VCAM-1 expression in a concentration-dependent manner. TNF-α induced p38 and extracellular signal-regulated kinase 1/2 (ERK1/2) activities that contributed to VCAM-1expression was obviously attenuated after pre-treating RAECs with paeonol. The decrease of VCAM-1 expression by paeonol pretreatment led to a reduction of monocytes adhesion to RAECs. Taken together, our results demonstrated that paeonol inhibited VCAM-1 expression by the attenuation of p38 and ERK1/2 signal transduction pathways. We concluded that paeonol had the potential therapeutic development for use in anti-inflammatory and vascular disorders.  相似文献   
59.
紫斑牡丹品种群是中国的主要牡丹品种群之一。文中描述了一个优良紫斑牡丹品种‘挽春’(Paeonia rockii‘Wan Chun’)的特征、习性和表现,该品种在紫斑牡丹品种群中具有代表性。紫斑牡丹品种可用于园艺观赏、经济林营造、荒山绿化以及荒漠治理。根据多年的调查和相关文献,按照紫斑牡丹品种的生长适应程度和引种栽培难易程度,将中国有可能引种栽植紫斑牡丹品种的地区划分为4类。介绍了各类地区在引种栽培方面需要注意的关键技术措施,分析了紫斑牡丹品种向全国各地推广过程中存在的问题,并提出了建议。  相似文献   
60.
丛枝菌根真菌对牡丹生长及相关生理指标的影响   总被引:7,自引:1,他引:6  
以采自山东省菏泽牡丹园的牡丹'凤丹'种子为试材,采用盆栽的方法研究了接种丛枝菌根(Arbuscular mycorrhizal,AM)真菌Glomus mosseae、Glomus versiforme和Glomus intraradices对牡丹幼苗生长及生理生化特性的影响.结果表明:(1)不同AM真菌的侵染率不同,并以G.mosseae的侵染率最高,为48.3%;(2)AM真菌能够促进牡丹幼苗生长,接种G.mosseae的植株干重比对照显著提高了69.5%;(3)AM真菌能够提高牡丹的叶绿素、可溶性糖、可溶性蛋白、矿质元素(N、P、K)含量和硝酸还原酶活性,并对可溶性蛋白含量和硝酸还原酶活性的影响达显著水平.(4)植株总干重与菌根侵染率、硝酸还原酶活性、叶绿素含量呈极显著正相关,与可溶性糖、可溶性蛋白含量呈显著正相关.研究发现,G.mosseae是最适宜牡丹接种的优良菌种.  相似文献   
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