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1.
RAPD analysis was applied to the three species of Asphodelus sect. Verinea (Pomel) Boissier (Asphodelaceae): Asphodelus fistulosus L., A. ayardii Jahand. & Maire, and A. tenuifolius Cav. Fifteen populations, five per species, were used and eight primers were sampled. A total of 97 amplification products were generated, and 4–12 polymorphic products per primer were obtained. Several specific RAPD markers were detected for A. ayardii and A. tenuifolius, while only two for A. fistulosus, which shares most amplification products with the two former species. Results that reinforce the specific status of the three taxa are shown. Asphodelus tenuifolius showed the highest interpopulation variability in agreement with the high specialization of other characters in this species. In accordance with these results, an amphidiploid origin for A. fistulosus, with the participation of A. ayardii and A. tenuifolius, is suggested. 相似文献
2.
Hideki Takahashi 《Journal of plant research》1994,107(3):237-243
Trillium apetalon Makino is unique amongTrillium in having apetalous flowers. Using scanning electron microscope, the early floral development was observed in comparison
with that ofT. kamtschaticum Pallas ex Pursh having petalous flowers. Morphologically petal primordia closely resemble stamen primordia in their more
or less narrow and radially symmetric shape and are clearly distinct from sepal primordia with broad bases. Early in floral
development sepal primordia are first initiated and subsequently two whorls of three primordia each are formed in rapid sequence,
the first three at the corners and the second three at the sides of the triangular floral apex. Based on comparison in position
and early developmental processes of their primordia, petals and outer stamens ofTrillium kamtschaticum are equivalent to outer stamens and inner stamens ofT. apetalon. The replacement of petals by outer stamens apparently leads to the loss of petals inTrillium apetalon flowers. Such a replacement can be interpreted in terms of homeosis. The replacement of the petal whorl leads to the serial
replacement of the subsequent whorls: outer stamens by inner stamens, and inner stamens by gynoecium inTrillium apetalon. The term ‘serial homeosis’ is introduced for this serial replacement. 相似文献
3.
J. O. Strandberg 《Plant Cell, Tissue and Organ Culture》1993,32(3):277-282
Meristems of Ophiopogon japonicus (Liliaceae) were grown on a modified MS medium without auxins or cytokinins and plantlets and embryogenic callus were obtained at a low frequency. When meristems growing on modified basal medium were briefly soaked in 0.54 mM naphtaleneacetic acid (NAA) or temporarily grown on medium that contained NAA or NAA and benzyladenine, a larger proportion of meristems developed into plantlets or produced callus and additional plantlets following their return to basal medium. Calluses grown in liquid culture without auxins or cytokinins produced abundant single cells and cell aggregates. Larger cell aggregates formed embryo-like structures that produced roots, cotyledons, and then plantlets following transfer to soilid medium. Prolonged liquid culture produced embryo-like structures directly in liquid medium. These structures met many of the criteria for somatic embryos and developed into normal plantlets when placed on solid medium. 相似文献
4.
LEONARD W. D. VAN RAAMSDONK JOOP P. VAN EIJK WIM EIKELBOOM 《Botanical journal of the Linnean Society. Linnean Society of London》1995,117(2):147-158
A range of almost 1400 cross combinations has been carried out between 31 species of Tulipa subgenus Tulipa. Most of the sections are well separated reproductively from each other. The designated species aggregates in section Clusianae appeared to be intersterile. Also in section Kolpakowskianae the species, as far as used, cannot be combined. Some crosses between species of section Tulipanum succeeded. The species of sections Eichleres and Tulipa (including the cultivated tulip T gesneriana) could be combined in various ways, although the highest level of seed set was achieved within either section. The crossability data support the current taxonomic division. The level of reproductive isolation between sympatric species is discussed, and the importance of crossability studies for plant breeding in Tulipa pointed out briefly. 相似文献
5.
6.
释百合科(广义)分类的沿革及对我国今后研究的展望 总被引:6,自引:0,他引:6
本文试图阐明近60年来一些作者对广义百合科所作的重大变革。广义百合科分类的变革不能不涉及其近缘科的分类,因此我们以Engler&Prantl(1930)的Liliiflorae目中的族作为基本单位,列表以明Hutchinson(1934)、Dahlgren et al.(1985,包括G.Dahlgren,989)、Takhtajan(1987)和Thorne(1992)各系统所作不同的处理。作者对Hutchinson的观点和其采用的分类特征作了较详细的介绍,因为他可能是对广义百合科作重大变革的第一个作者,而对Dahlgen et al.、Takhtajan和Thorne系统的介绍则较为简略。本文还讨论了科级范围大小的利弊,不同意有些作者仅仅将亚科或卫星类群都提升为科的作法。假如这种提升之后仍如原先的科保留于同一类群之中,而不作系统上的改变,则意义不大。
本文对Hutchinson、Takhtajan和Dahlgren et al.(1985)的单子叶植物起源的假说也作了介绍。虽然Dahlgren et al.的见解未被大多数作者所接受,但他们的方法论值得注意。基于单子叶植物和双子叶植物的共性,他们假设出一个臆想的分类群,从这个臆想的分类群演进到一个单子叶植物祖先只需经过最少的步段。这样的一个单子叶植物祖先现在是不存在的,但最接近它的是现存的Trichopus(隶Trichopodaceae,Dioscordales)。Trichopus肯定不是单子叶植物和双子叶植物之间的一个直接联系的纽带,但它有许多特征可以在Annonales(隶lianae超目)中找到。因此,他们认为Dioscoreales是最不特化的单子叶植物,把它作为百合超目的第一个目,置于单子叶植物系统的最前位置。本文作者最后对今后我国开展广义百合科研究提出一些建议,其中以选择一些分布于北半球类群,如Lilium,Monocharis,Paris等等,作广泛研究(可从形态学、细胞学、分子系统学三个层次进行)最为现实,因为对它们取材比较容易。 相似文献
7.
Seven-day-old leek seedlings actively synthesize lipids in vivo from [1-14C]acetate, both in the light and in the dark. In the dark, phospholipid synthesis is more effective than galactolipid synthesis. Whatever the time of acetate incorporation by the etiolated seedlings, very long chain fatty acids having from 20 to 26 carbon atoms are found in all the polar lipids, including the acyl-CoAs. All of the labelled very long chain fatty acids incorporated into the polar lipids are saturated. On the other hand, the labelled C18-fatty acids are unsaturated in phospholipids and galactolipids and almost no label is found in the saturated or unsaturated C18-fatty acids of the acyl-CoAs. 相似文献
8.
The constituents of the steam volatile oils from two kinds of Allium fistulosum, A. fistulosum var. caespitosum and A. chinense, have been investigated by GC and spectral techniques (IR, UV, GC/MS, 1H NMR and 13C NMR). The compounds identified from the neutral fraction of each volatile oil included sulphides, thiolanes, alcohols, aldehydes, ketones, furanones and others. Among the sulphur compounds, dipropyl disulphide comprised ca 28% of A. fistulosum oil, ca 23% of A. fistulosum var. caespitosum oil and ca 30% of A. chinense oil. A. fistulosum oil was characterized by a large quantity of tridecan-2-one (ca 52%) and 2,3-dihydro-2-octyl-5-methylfuran-3-one (ca 16%). Also, a large amount of 2,3-dihydro-2-hexyl-5-methylfuran-3-one (ca 20%) was isolated from A. chinense oil. 相似文献
9.
Junichi Kitajima Tetsuya Komori Toshio Kawasaki Hans-rolf Schulten 《Phytochemistry》1982,21(1):187-192
From the aerial parts of Fritillaria thunbergii, three glycosidal Solanum alkaloids (basic steroid saponins) were isolated together with minor 相似文献
10.
The polysaccharide component of the stigmatic exudate from Lilium longiflorum has the composition, arabinose (26%), rhamnose (6%), galactose (57%) and glucuronic acid (11%). The highly branched polysaccharide bears a striking resemblance to the acidic polysaccharide exudate from Araucaria bidwillii in belonging to the galactan group and in carrying outer chains terminated by arabinofuranose, rhamnopyranose, galactopyranose and glucuronic acid residues. Both polysaccharides contain the sequence O-rhamnopyranosyl-(1→4)-glucopyranosyluronic acid-(1→6)-galactopyranose in some of the outer chains. 相似文献