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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
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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
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铁线莲属为毛茛科中具有重要园艺学价值的世界性大属。近年来,国内外专家学者发表了许多铁线莲属分类学、分子系统学和系统基因组学研究文献,使人们对该属的认识与界定发生了巨大的改变。以往分类学上承认的互叶铁线莲属、锡兰莲属等铁线莲亚族中的小属,根据分子系统学研究结果,均应并入铁线莲属中。因此,铁线莲属所包含的植物资源比以前的认识要更加丰富。该研究在以往分类学与分子系统学研究基础上,整理了广义铁线莲属各个属下分类群的野生植物资源状况以及它们的园艺学价值,为我国铁线莲属园艺植物资源开发、利用与保护提供参考。 相似文献
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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
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Emmy Dhooghe Sylvie Denis Tom Eeckhaut Dirk Reheul Marie-Christine Van Labeke 《Euphytica》2009,168(1):33-40
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
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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
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Embryo development followed by seed germination was investigated in seeds of Christmas rose (Helleborus niger) held under different temperature conditions. The seeds had a heart-shaped embryo when dispersed from parent plants. That embryo developed rapidly to the torpedo stage at 25 °C, after which no further development occurred. When seeds with a torpedo-stage embryo were held at 15 °C, the embryos developed to the cotyledon stage, but no further germination occurred. Similar phenomena in the course of embryo development were observed in seeds held in a non-heated polyethylene house, in which the embryos developed to the torpedo stage at 20 °C or more, while further development to the cotyledon stage was attained only at temperatures of 15 °C or less. Seeds with a cotyledon-stage embryo rarely germinated until they were treated at 4 °C for more than 8 weeks. These results suggest that seeds of H. niger have a deep, simple morphophysiological dormancy caused by the combination of rudimentary embryos and a physiological dormancy that can be broken by cycles of warming and chilling. 相似文献