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71.
类黄酮3-O-糖基转移酶(flavonoid 3-O-glucosyltransferase,UF3GT)可以把不稳定的花色素催化成花色素苷。本研究采用同源基因克隆技术获得箭叶淫羊藿Epimedium sagittatum(Sieb.and Zucc.)Maxim.UF3GT基因c DNA开放阅读框(Open Reading Frame,ORF)序列,命名为Es UF3GT(Gen Bank注册号为KJ648620)。序列分析表明,该基因ORF全长为1356 bp,编码451个氨基酸,与其它植物中UF3GT蛋白序列的相似性为40%~50%。进化树分析发现,Es UF3GT同催化类黄酮3-O糖基化的糖基转移酶聚为一枝。qRTPCR分析结果显示,Es UF3GT在花中的表达量最高,约为叶片、花蕾中表达水平的2.3倍,果实及根中表达水平的19倍。花青素含量检测表明,花蕾中的含量最高(130.4 mg/100 g),分别是叶片、花、果实及根中含量的3.5、5.2、72、87倍。我们推测Es UF3GT参与了箭叶淫羊藿花色素苷的生物合成,此结果为深入开展EsUF3GT的生化功能研究奠定了基础。 相似文献
72.
Pollen morphology of Daphne genkwa Sieb.et Zucc.was observed by scanning electron microscope(SEM),and its viability and germination rate were measured by TTC and sucrose in vitro culture methods.The results show that pollen is stenopalynous type with a diameter of 15.6-21.6 μm.Per pollen has 10-16 apertures which is irregular circular with a diameter of 1.4-2.0 μm.Surface ornamentation of pollen is rough reticulate pattern which is circular polygon(tetragon-heptagon,mostly pentagon-hexagon).Pollen viability is 51% by TTC.Sucrose of different concentrations has a significant effect on pollen germination rate during pollen culture.And pollen germination rate is the highest with a percentage of 27.0% in medium containing 50 g·L-1 sucrose,while pollen could not germinate in medium containing sucrose over 250 g·L-1.Otherwise,there is the phenomenon of "multi-aperture germination" during pollen germinating. 相似文献
73.
本实验采用薄层色谱法对川楝子中香草酸、异香草酸进行定性鉴别;采用高效液相色谱法对川楝子中香草酸进行含量测定。色谱柱:Hypersil BDS C18(250 mm×4.60 mm,5μm),柱温:30℃,流动相:甲醇∶水∶冰乙酸=25∶75∶0.5,流速:1.0 mL.min-1,检测波长:260 nm。最终,定性鉴别斑点清晰。结果表明香草酸含量在1.022~16.352μg范围内,进样量与峰面积呈良好线性关系,相关系数r=0.9998;香草酸的平均回收率为102.45%,RSD=1.22%(n=6)。 相似文献
74.
赖广辉 《热带亚热带植物学报》2015,23(1):17-24
刚竹属(PhyllostachysSieb. et Zucc.)是一个主产于中国,大约有60种的竹亚科大属,当前其属内种间的划分和鉴定主要依据秆箨和新秆的特征。然而,本属植物的笋期大多仅持续20~30 d,其他时间很难见到鲜笋或新鲜秆箨和新秆。应用现今流行的分种检索表和形态特征来鉴别处于非笋期营养生长状态的竹种往往作用不大,这就需要重新寻找更多的证据来解决这一问题。据长期的野外调查和栽培植物的定点观察,一些性状,如秆的节内距、小枝及叶的排列方式、叶耳及繸毛存在与否及其排列方式、叶舌是否伸出、叶片背面毛被状况等可以作为本属植物非笋期分类的重要依据。如果把握得恰当,利用这些性状和其他特征的组合可以在非笋期将本属现知的所有竹种划分开来,并据此编制了此期的分种检索表。 相似文献
75.
Cinnamomum japonicum Sieb. is an excellent roadside tree and medicinal tree species with considerable ornamental and economic value. In this study,
we successfully developed a large-scale micropropagation protocol for C. japonicum for the first time. Sterilized shoots were excised and used as explants for
shoot induction on several basal media, supplemented with different concentrations
of plant growth regulators (PGRs), such as Thidiazuron (TDZ), N6
-Benzyladenine
(6-benzylaminopurine) (BA), α-naphthaleneacetic acid (NAA) and Gibberellic acid
(GA3). After comparison, the most efficient medium for shoot regeneration
was 1/2 Murashige and Skoog (MS) medium containing 0.5 mg L–1 BA,
0.05 mg L–1 NAA and 0.2 mg L–1 GA3, which resulted in an average number of
induced shoots per explant and shoot length of 5.2 and 1.62 cm at 28 d, respectively. Then, elongated adventitious shoots were transferred to induce roots.
86.7% of shoots was able to root on 1/2 MS medium supplemented with 0.5 mg
L–1 NAA and 0.1 mg L–1 BA. The earliest rooting time observed was after 21 d
and the average root length was up to 3.3 cm after 28 d. Our study shows that
C. japonicum can be successfully regenerated through de novo organogenesis,
which lays a foundation for future transformation research on this tree. 相似文献
76.
The genetic diversity and genetic relatedness of mei (Prunus mume; 2n = 16) were studied using amplified fragment length polymorphism (AFLP) markers. Eight EcoRI–PstI AFLP primer combinations were applied to 121 distinct genotypes of mei cultivars and related species. A total of 508 AFLP
product bands were produced, of which 382 were polymorphic. The unweighted pair group method with arithmetic averages analysis
was carried out based on these AFLP markers. From this analysis, “Qugeng Mei,” “Yan Mei,” “Chaodou Mei,” and mei cultivars
were seen to share the same P. mume genetic stem. The AFLP data were able to clearly discriminate P. mume from other species in the genus Prunus, with P. armeniaca aligning as its closest related species. Two major groups and nine subgroups of mei flower were identified, and there was
a strong coincidence of these AFLP-based groupings with the respective morphological characters of the accessions. The genetic
diversity of mei accessions was greatest in the Yunnan Province and decreased toward Eastern China and Japan, so supporting
the hypothesis that the southwest of China represents the genetic diversity center of the species. 相似文献
77.
山东赤松种群的个体生长规律 总被引:2,自引:0,他引:2
利用Logistic增长模型对山东赤松 (PinusdensifloraSieb .etZucc .)种群个体生长规律进行了初步研究。结果表明 ,赤松个体生长密切符合Logistic方程 ;人工林个体生长好于天然次生林 ;人工林与次生林个体生长规律一致 ;树高成熟龄和连年生长量最大时年龄出现最早 ,胸径成熟龄和连年生长量最大时年龄出现较晚 ,材积成熟龄和连年生长量最大时年龄出现最迟 相似文献
78.
Tianli Tian Qiling Sun Jing Shen Tao Zhang Pei Gao Qun Sun 《World journal of microbiology & biotechnology》2008,24(6):861-866
Rhizopus microsporus isolated by our laboratory was able to transform polydatin into resveratrol and emodin-8-β-d-glucoside into emodin, respectively, through the fermentation of Polygonum cuspidatum Sieb. et Zucc. The fermentation products were separated and purified by H1020 resin and silica gel column chromatography.
Thin layer chromatography (TLC) and high performance liquid chromatography (HPLC) were used to identify the products and evaluate
the transformation efficiency. A variety of parameters of submerged state fermentation, including the growth characteristics,
the change of β-glucosidase activity and the amount of polydatin, resveratrol, emodin-8-β-d-glucoside, emodin, and the dissolved oxygen, were monitored simultaneously. The amount of resveratrol yielded increased dramatically
from 0.04 g/l at the beginning to the maximum value of 0.34 g/l at 36 h of fermentation, and emodin was from 0.4 g/l to 0.65 g/l
at 80 h. The transformation rate of glycosides reached 98% and the purity of both resveratrol and emodin was 95%. 相似文献
79.
The occurrence of clonal growth of distylous Lithospermum caroliniense was investigated in a population in the Nebraska Sandhills, an area where sand dunes have been relatively stable for at least 1500-3000 yr, and compared to a population occurring at the Indiana Dunes, an area of active sand dune formation. Spatial autocorrelation analysis indicated the occurrence of significant clonal propagation of genetically based floral morphs at Arapaho Prairie, but not for the Indiana Dunes. Apparent clonal growth in the Sandhills population had no overall negative effect on pollen deposition or fecundity relative to the Indiana population, although in some large clones the proportion of compatible pollen grains on stigmas was lower. Clonal growth may have occurred in the Sandhills population because of the greater age and stability of the Nebraska Sandhills; infrequent establishment of seedlings permits detection of clonal growth using the spatial pattern of floral morphs. At the Indiana dunes, repeated cycles of dune formation provide conditions favoring establishment of seedlings, and sand dune succession results in disappearance of L. caroliniense before the development of clones. 相似文献
80.
Bulgakov VP Veselova MV Tchernoded GK Kiselev KV Fedoreyev SA Zhuravlev YN 《Planta》2005,221(4):471-478
Rabdosiin and related caffeic acid metabolites have been proposed as active pharmacological agents demonstrating potent anti-HIV and antiallergic activities. We transformed Eritrichium sericeum and Lithospermum erythrorhizon seedlings by the rolC gene, which has been recently described as an activator of plant secondary metabolism. Surprisingly, the rolC-transformed cell cultures of both plants yielded two- to threefold less levels of rabdosiin and rosmarinic acid (RA) than respective control cultures. This result establishes an interesting precedent when the secondary metabolites are differently regulated by a single gene. We show that the rolC gene affects production of rabdosiin and RA irrespective of the methyl jasmonate (MeJA)-mediated and the Ca2+-dependent NADPH oxidase pathways. Cantharidin, an inhibitor of serine/threonine phosphatases, partly diminishes the rolC-gene inhibitory effect that indicates involvement of the rolC-gene-mediated signal in plant regulatory controls, mediated by protein phosphatases. We also show that the control MeJA-stimulated E. sericeum root culture produces (–)-rabdosiin up to 3.41% dry weight, representing the highest level of this substance for plant cell cultures reported so far. 相似文献