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71.
Foliar sclereids in the Magnoliaceae 总被引:4,自引:0,他引:4
SHIRLEY C. TUCKER 《Botanical journal of the Linnean Society. Linnean Society of London》1977,75(4):325-356
The foliar sclereids in 136 species representing 11 of the 12 genera of Magnoliaceae were studied and compared. Sclereids occur in four different cell assemblages within the leaf: diffuse idioblasts, mesophyll, dermal system, and the vein sheath including terminal elements. Tropical members tend to have the most highly sclerified leaves. In species of Manglietia the leaves have sclerified spongy mesophyll and either sclerified epidermis or hypodermis. In Talauma , sclerification affects the vein sheath and terminal cells of veinlets, with a specialized thick marginal vein in the Asian taxa but not in the American ones. Liriodendron and the magnolias native to the north temperate zone have only minimal sclerification, which usually is confined to the vein sheath of the midrib and the main lateral veins, and as idioblastic sclereids in the petiole and the midrib near the base of the blade. The two largest genera Magnolia and Michelia are heterogeneous and include species which vary as to their combinations of sclerified elements among the four possible types. 相似文献
72.
Investigation of the cytotoxic active components of Michelia compressa afforded two new cytotoxic sesquiterpene lactones, michelenolide and micheliolide. Parthenolide, costunolide, santamarine, reynosin and liriodenine were also isolated and exhibited cytotoxic activity. The known sesquiterpene lactones, lanuginolide and dihydroparthenolide, were isolated but were not active. Two other new inactive sesquiterpene lactones, compressanolide and dihydroreynosin, were also obtained. The structures of michelenolide and micheliolide were confirmed by partial synthesis from parthenolide and the structure of compressanolide by partial synthesis from dihydroparthenolide. 相似文献
73.
Four lignans were isolated from the flower buds of Magnolia fargesii Cheng, two of which were known lignans, pinoresinol dimethyl ether and lirioresinol-B dimethyl ether; the other two were new lignans, magnolin and fargesin, and their structures have been determined by spectroscopic studies. 相似文献
74.
Ahmed F. Halim El-Sayed S. Mansour Farid A. Badria Jürgen Ziesche Ferdinand Bohlmann 《Phytochemistry》1984,23(4):914-915
The leaves of Magnolia grandiflora afforded in addition to costunolide diepoxide and parthenolide a guaianolide named magnograndiolide. 相似文献
75.
76.
湖南植物志资料(一)木兰科、八角科、五味子科、樟科、水马齿科补遗 总被引:3,自引:0,他引:3
本文报道了湖南植物新记录共计11种,隶属于5科10属.归并樟科植物3种2变种:将石木姜子LitseafaberiHemsl.和近轮叶木姜子L.subverticillataYang归入黄丹木姜子L.elongata(Wall.exNees)Benth.etHook.f.,将长梗绒楠MachilusvelutinaChamp.exBenth.var.lingipedunculataC.J.Qi归入绒毛润楠M.velutinaChamp.exBenth.,将短梗新木姜子NeolitseabrevipesH.W.Li归入美丽新木姜子N.pulchella(Meissn)Merr.,将紫云山新木姜子N.wushanica(Chun)Merr.var.pubensYangetP.H.Huang归入巫山新木姜子N.wushanica(Chun)Merr.. 相似文献
77.
78.
濒危植物长蕊木兰的核型 总被引:1,自引:0,他引:1
报道了长蕊木兰(Alcimandra cathcartii)的染色体核型,核型公式为2n=2x=38=22m+15sm(3sat)+1st。核型类型属于Stebbins的2A型。第18条染色体为st染色体,第5、6、7条sm染色体的短臂上各具有1个随体。间期核为简单染色中心型(simple chromocenter type),有丝分裂前期染色体为中间型(interstitial type)。对前人关于木兰属和含笑属植物的核型研究结果进行了比较分析,长蕊木兰与含笑属亲缘关系较近,但稍有区别,而与木兰属的亲缘关系较远。 相似文献
79.
乐昌含笑(木兰科)的核型研究 总被引:3,自引:0,他引:3
首次报道了乐昌含笑(Michelia chapensis)的染色体数目和核型。核型公式为2n=38=28m 6sm 4st(2SAT)。与前人认为整个含笑属都为单一的2A型不同,乐昌含笑的核型属于Stebbins的2B型,具有2对近端着丝粒染色体。而且发现在第9对染色体上有小随体的存在。这些表明在含笑属内含有不同的核型。乐昌含笑在细胞学意义上可能是属内比较进化的类群。对染色体结构的细微改变在木兰科植物的种属进化上的作用进行了简要讨论。 相似文献
80.