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1.
程薪宇  刘玫  郭梦桥 《草业学报》2015,24(3):168-176
本文采用形态观察及GMA半薄切片法深入研究了毛茛科18属,37种,及5变种的雄蕊形态结构。结果显示雄蕊表面无毛或被非腺毛及腺毛。花丝呈丝状、条状、棒状、长三角形或短柱状,其薄壁组织胞间隙不明显或发达。花药侧面观为∞形、椭圆形、近圆形或条形;幼嫩花药横切面形状变化较大,为V形、Λ形、椭圆形、方形、∞形或蝶形;花粉囊间薄壁细胞排列呈V形、Λ形或直线形。成熟花药的花粉囊间薄壁细胞消失。部分幼嫩时横切面∞形的花药,成熟时变为椭圆形,而蝶形和方形的花药则变为∞形。花药及花丝的特征在属及种内是稳定的,可作为毛茛科属及组的分类学证据。本文完善了毛茛科花形态学研究,为进一步研究毛茛科系统学提供了新的形态学基础。  相似文献   
2.
Helleborus species are members of the family of the Ranunculaceae. These popular perennials are all diploids (2n = 2x = 32). This study investigates polyploidy induction by different antimitotic agents. Colchicine, oryzalin and trifluralin were tested in vitro on shoots of Helleborus niger, H. orientalis and H. × nigercors. Furthermore the effect of the antimitotic agents on the viability and the multiplication rate of cultured plantlets were analyzed. Flow cytometry demonstrated that polyploidisation was genotype dependent: using H. niger, tetraploids were obtained using either oryzalin (3 μM) or trifluralin (3 or 10 μM), whereas for H. × nigercors only trifluralin (3 or 10 μM) induced polyploidisation. For H. orientalis neither treatment was effective to produce tetraploids or mixoploids. For these three species, colchicine (100 μM) was ineffective. The polyploidisation events in H. niger and H. × nigercors were confirmed by chromosome counts of mounted nuclei derived from root tips (2n = 4x = 64).  相似文献   
3.
姜治国  廖明尧 《安徽农业科学》2010,38(24):13167-13167
介绍了湖北亚热带地区1个新记录属——毛茛科美花草属和1个新记录种——太白美花草。  相似文献   
4.
毛茛科杀虫植物——乌头   总被引:7,自引:0,他引:7  
论述了毛茛科杀虫植物乌头Aconitum Carmichaeli的分布、生物学特性、毒性、药用性和生物活性,并讨论了其作为杀虫植物的应用前景。  相似文献   
5.
孟有儒 《草业科学》2003,20(12):78-79
甘肃寄生毛茛科牧草的霜霉菌3种,轴霜霉菌2种,均发生在高寒阴湿草地,零星发生。  相似文献   
6.
Phytochemical investigation of Helleborus niger L. (Ranunculaceae) leaf methanol extract allowed to isolate a phenolic glucoside derivative and two flavonoid glycosides characterized as phenyllactic acid 2-O-β-d-glucopyranoside (1), quercetin 3-O-2-(E-caffeoyl)-α-l-arabinopyranosyl-(1 → 2)-β-d-glucopyranoside-7-O-β-d-glucopyranoside (2), and kaempferol 3-O-α-l-arabinopyranosyl-(1 → 2)-β-d-galactopyranoside-7-O-β-d-glucopyranoside (3), respectively. Compounds 1 and 2 were isolated for the first time and their structural characterization was obtained on the basis of extensive NMR spectral studies.  相似文献   
7.
This study investigates the capacity of the antimitotic agents colchicine, oryzalin and trifluralin for inducing polyploidisation of Ranunculus asiaticus ‘Alfa’ in vitro shoots. Flow cytometry was used to evaluate the optimal concentration of each antimitotic agent for polyploidisation. Trifluralin at a concentration of 2 μM resulted in the highest percentage of polyploidisation (27.5%), followed by a colchicine treatment of 200 μM, which induced 23.3% of polyploids. For oryzalin the highest percentage was achieved using a concentration of 1 μM. Different exposure periods were tested and turned out to be an important factor. The maximal exposure period tested (10 weeks) resulted in a significant increase in polyploidisation by oryzalin and trifluralin. In contrast, for colchicine (100 μM) exposure times of either 16 or 24 h did not significantly influence polyploidisation. Additionally the effect of the antimitotic agents on the viability was analysed. For colchicine no significant effect on the survival rate was observed, for trifluralin only a concentration of 10 μM affected viability whereas for oryzalin, concentration as well as exposure period were significant parameters. Flow cytometric data were confirmed by counting chromosomes in root tip cells.  相似文献   
8.
Six flavonol glycosides, compounds 1-3 from A. burnatii Gáyer and 4-6 from A. variegatum L., were obtained from their methanol extracts of aerial parts. The identified structures were quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-p-coumaroyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (1), quercetin 3-O-β-d-glucopyranoside-7-O-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (2), quercetin 3-O-β-d-glucopyranoside-7-O-(6-E-caffeoyl)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside (3), kaempferol 3-O-β-d-galactopyranoside-7-O-α-l-arabinopyranoside (4), quercetin 3-O-β-d-glucopyranoside (5), and kaempferol 3-O-β-d-glucopyranoside (6). Compounds 1, 2 and 4 were isolated for the first time. The antioxidant potential of the methanol extracts and pure compounds was tested with different assays.  相似文献   
9.
马红梅  张静  王红丽  张帆 《安徽农业科学》2014,(7):1931-1932,1945
[目的]对野生乌头药材生存土壤环境进行理化分析和元素检测。[方法]利用实地考察采样和物理化学方法、光谱技术检测乌头生存土壤的容重、孔隙度、水分、pH值,以及有机质、碱解氮、速效磷和营养元素的含量。[结果]不同地区乌头生长土壤环境的理化性质差异较小,但是有机质与营养元素含量的差别较大。[结论]乌头类药材对生存环境要求较低,适应能力较强,呈现一定的规律性,试验指标和参数可为该类药材道地适应性、区域区划提供核心数据,并为将来建立乌头药材GAP基地提供科学依据。  相似文献   
10.
白芍中两个单萜苷的结构鉴定   总被引:1,自引:0,他引:1  
采用硅胶柱色谱法从白芍中得到蒎烷型单萜苷类成分芍药苷、白芍苷和芍药新苷外,进一步分离得到2个同类化合物Ⅰ和Ⅱ以及苯甲酸,Ⅰ、Ⅱ分别为白芍新苷和4-O-乙基芍药苷(4-O-ethy lpaeon iflorin),通过波谱分析鉴定了它们的结构,并明确归属了Ⅰ和Ⅱ的1H和13C NMR信号。  相似文献   
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