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杉科植物的分类学研究 总被引:10,自引:0,他引:10
本文对杉科植物的研究历史作了回顾,根据分支分类结果和表征分类结果,提出了一个新的分类系统.以形态学为依据,结合其他学科的研究成果,对杉科的分类作了订正。作者承认杉科植物共9属、12种及3变种,将杉木、厚皮杉木、德昌杉木和米德杉木归并,支持柳杉作为日本柳杉的变种、台湾杉木作为杉木的变种、秃杉和台湾杉归并的观点。 相似文献
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采用缩微实验法 ,初步系统研究了杉木叶凋落物分别与火力楠、红栲和木荷 3个阔叶树种之一的叶凋落物两两混合分解的动态变化 ,以探明凋落物混合分解过程中可能存在的相互作用 .结果表明 ,杉木叶凋落物与 3种阔叶树种叶凋落物两两混合分解时所表现出不同的相互作用形式 :杉木与木荷表现出抑制作用 ,杉木与红栲或火力楠表现为较弱的促进作用 . 相似文献
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Cunnighamia unicanaliculata D. Y. Wang et H. L. Liu and var. pyramidalis D. Y. Wang et H. L. Lin, two new taxa recently found in south-western Sichuan Province of China, have both a very restricted yet sympatric geographical distribution, including Dechang and Miyi districts.[7] There is a debate as regards the specific status of C. unicanaliculata. A comparative karyological investigation, including chromosome numbers, karyotype analyses and measurements of nuclear volume and DNA contents, was under- taken in order to shed some light on the phylogenetic relationships between these taxa and C. lanceolata (Lamb.) Hook. The kaxyotype formulas of the above two taxa and C. lanceolata are as follows: C.unicanaliculata; K(2n) = 22 =L8m+ S12m+S2sm; C. unicanaliculata var. pyramidalis: K(2n)= 22= L8m +S10m+S4sm; C. lanceolata (Type A): K(2n) =22 = Lsm+ S14m S2sm; C. lanceolata(TypeB): K(2n) = 22 = L8m + S14m . Frown the above karyotypes, we have found that C. unicanaliculata and var. pyrami- dalis, which are very similar to each other, are closely related to C. lanceolata (Type B), but seem more strongly differentiated in the following respects: (1) the former posses- sing 1--2 pairs of chromosomes with submedian primary constrictions each, while the latter with all chromosomes possessing median primary constrictions; (2) the satellites of the former being always located on the 4th pair of chromosomes, whereas the position of satellites of the latter varying with geographical distribution, being usually on the 1st and 4th pairs of chromosomes; (3) B-chromosomes being present in the latter (predominantly in the geographical races of southwestern China) but not seen in the former; (4) the average chromosome volume of C. unicanaliculata var. pyramidalis being 623.44, while those of the four geographical races of C. lanceolata being 667.2–796.0; (5) the comparative DNA amount of C. unicanaliculata var. pyramidalis being 5.54, while those of the various geographical races of C. lanceolata being 6.20–7.67. Upon an overall comparison of the data with regard to karyology, geographical distribution, ecology, morphology and isoenzymic patterns of the taxa in question, we come to the following conclusions. Cunninghamia unicanaliculata and var. pyramidalis are most likely taxa originated from natural populations of C. lanceolata. The extreme environmental conditions of the habitats axe thought to have played an important role in the production of these two new taxa. An elevation of over 2000 meters and the periodical aridity of climate of the habitat, which differed remarkably from those of C. lanceolata, made possible the isolation of alternative populations, accompanied by selection for adaptation to extreme environments. But the differences between these two newly found taxa and C. lanceolata are karyologically minor and morphologically quantitative and tend to display a more or less continuous variation pattern. It is, therefore, suggested that they are probably geographical races or ecotypes of C. lanceolata, and are not distinct enough from the latter to warrant specific status. It seems best to treat both C. unicanaliculata and var. pyramidalis as infraspecific catorories of C. lanceolata. 相似文献
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The physico-chemical properties of Spondias mombin seed oil and the viscosity-temperature profiles of six seed oils from other plants which grow in the wild: Balanites aegytiaca, Lophira lanceolata, Sterculia setigera, Khaya senegalensis, Ximenia americana and Sclereocarya birrea, were investigated. The oil content of S. mombin seed was significant at 31.5% (w/w). The oil appeared stable as deduced from its low peroxide and acid values of 6.0 mEq kg(-1) and 1.68 mg KOH, respectively. The X. americana oil was denser than the other ones, with a value of 0.9625 g cm(-3) at 30 degrees C. The kinematic viscosities of the oils and their temperature dependence in the range 30-70 degrees C suggested a potential industrial application of the oils as lubricating base stock. Specifically, the kinematic viscosities of the oils were in the range 59.8-938.2 cst at 30 degrees C with X. americana having the highest value. At 70 degrees C, the reduction in viscosities of the oils was marked: reduction by over 70% of their values at 30 degrees C for S. setigera, K. senegalensis, X. americana and S. birrea oils. 相似文献
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ETELKA A. LEADLAY VERNON H. HEYWOOD † 《Botanical journal of the Linnean Society. Linnean Society of London》1990,102(4):313-398
In this treatment, the genera Coincya (synonym: Hutera ) and Rhynchosinapis are regarded as one genus under the name Coincya which has nomenclatural priority. This study is based on data from morphology, population studies, cytology, ecology and reproductive biology reinforced by breeding experiments. Coincya is a west European genus comprising 14 taxa (including six species, five subspecies and three varieties).Eight new combinations are proposed and two species are excluded; R.nivalis is referable to the genus Brassica and R. Leplocarpa is probably referable to Erucastrum.
The chromosome number is either 2 n = 24 or 2 n = 48, which confirmed previous counts; C. Transtagana has not been counted. Breeding experiments were carried out with C. Longirostra, C.rupestris, C.monensis subsp. monensis , diploid and tetraploid races of subsp. recurvata var. recurvata , var. johnslonii , var. setigera , var. granatensis , subsp. hispida and subsp. puberula.
All taxa tested are outbreeding with a genetic self-incompatibility mechanism and are cross-compatible, suggesting that there has been no cytological differentiation between the diploid species in this study. The tetraploids formed semi-sterile triploids when crossed with diploids and although the chromosomes only formed bivalents and trivalents at meiosis it was postulated that the tetraploid was an autotetraploid of polytopic origin.
The evolution and differentiation of the genus and species are discussed. 相似文献
The chromosome number is either 2 n = 24 or 2 n = 48, which confirmed previous counts; C. Transtagana has not been counted. Breeding experiments were carried out with C. Longirostra, C.rupestris, C.monensis subsp. monensis , diploid and tetraploid races of subsp. recurvata var. recurvata , var. johnslonii , var. setigera , var. granatensis , subsp. hispida and subsp. puberula.
All taxa tested are outbreeding with a genetic self-incompatibility mechanism and are cross-compatible, suggesting that there has been no cytological differentiation between the diploid species in this study. The tetraploids formed semi-sterile triploids when crossed with diploids and although the chromosomes only formed bivalents and trivalents at meiosis it was postulated that the tetraploid was an autotetraploid of polytopic origin.
The evolution and differentiation of the genus and species are discussed. 相似文献
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重楼属的四个新异名 总被引:1,自引:0,他引:1
将小重楼Paris polyphylla Smith var.minora S.F.Wang、长药隔重楼P.polyhylla Smith var.pseudothibetica H.Li处理为金线重楼P.delavayi Franch.的异名;将广东重楼P.polyphylla Smith var.kwantungensis(R.H.Miau)S.C.Chen&S.Y.Liang处理为多叶重楼P.polyphylla Smith的异名;将文县重楼P.wenxianensis Z.X.Peng&R.N.Zhao处理为黑籽重楼P.thibetica Franch.的异名。 相似文献
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After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc., S. elliptifolium C. F. Wei and S. integrifolium var. glaucescens Rehder were reduced to synonyms of S. hypoglaucum Rehder and S. integrifolium f. cordatum S. Y. Wang was reduced to synonym of S. corylifolium Chun. Schizophragma crassum var. ellipticum J. Anthony was treated as the correct name of S. crassum var. hsitaoanum (Chun) C. F. Wei. The name S. integrifolium var. minus Rehder is reinstated. The taxonomic treat-ment is supported by leaf epidermal characters. 相似文献
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将伏牛海棠Malus komarovii Rehd. var.funiushanensis S. Y. Wang作为异名归并入陇东海棠Maluz kansuensis(Batal.)Schneid.。 相似文献
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披针叶黄华应用已久 ,尽管该种的学名为一异名 ,但该名称的保留有利于保持该类群在分类学上的稳定性 ,建议保留该种名 相似文献
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木犀科丁香属的一个新等级和六个名称的模式指定 总被引:1,自引:0,他引:1
在居群取样、标本查阅、性状分析和多变量分析的基础上, 提出了丁香属Syringa一个新等级和一个新异名: 辽东丁香S. wolfii C. K. Schneid.被处理为红丁香的亚种S. villosa ssp. wolfii而不是垂丝丁香的亚种S. reflexa ssp. wolfii, 并且其后选模式被指定。同时还指定了五个异名的后选模式, 它们是S. bretschneiderii、S. emodi var. rosea、S. villosa var. hirsuta、S. formosissima和S. robusta。 相似文献
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Ku Tsue-Chih 《植物分类学报:英文版》1991,29(1):80-83
In the present paper, we new species and two new varieties of Saxifragaceae and Rosaceae are described from the Hengduan Mountains. They are Philadelphus lushui-ensis Ku et S. M. Hwang, Parnassia lanceolata Ku var. oblongipetala Ku, P. nubicola Wall.ex Royle var. nana Ku and Malus muliensis Ku. 相似文献
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对国产黄杨科5 种植物作了分类学修订或补充: 将雀舌黄杨归入匙叶黄杨, 中间黄杨归入黄杨, 多毛板凳果归入板凳果, 双蕊野扇花归入羽脉野扇花; 恢复黄杨和尖叶黄杨的原学名;报道宜昌黄杨在湖南的新记录。 相似文献
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值得注意的中国植物(续) 总被引:1,自引:1,他引:0
续报道了大戟科等 8个分类单位。大果留萼木 ( Blachia andamanica)为广东和海南的新记录 ;崖州留萼木 ( B.jatrophifolia)的新异名为 B.yaihsienensis;黄毛果巴豆 ( Croton lachynocarpusvar.kwangsiensis)是降级新组合 ;黄蓉花 ( Dalechampia bidentata)分布至云南西南部 ,D. bidentata var. yunnanensis为其新异名 ;海人树 ( Suriana maritima) ,广东省的东沙群岛才有 ,台湾不产 ;锥序丁公藤 ( Erycibe subspicata)其分布东缘在贵州西南部 ;头花小牵牛 ( Jacquemontia tamnifolia) ,广东的归化杂草 ;松下草 ( Petrosavissinii) ,广东新记录 相似文献