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1.
栝楼属植物种子油中特殊脂肪酸成分的研究   总被引:1,自引:0,他引:1  
黄民权 《植物研究》1986,6(1):79-83
栝楼属(Trichosanthes)属葫芦科,系多年生草质藤本植物。全世界有60余种,我国分布55种。中药栝楼为葫芦科植物栝楼(Trichosanthes ki-rilowii Maxim.)的果实,本植物的根(天花粉),果皮(栝楼皮),种子(栝楼子)均供药用,具抗菌抗癌作用[1],为一种重要的中药。该属植物的种子富含油脂,我们所研究的样品,多数含油率都在20%以上。本文研究了该属七种植物的种子油,经气相色谱分析,紫外和红外光谱鉴定,同时采用安石榴(Punica granatum L.)种子油中的石榴酸作标准样品进行相应的平行测定作参照,证实这七种种子油均含有石榴酸,而且含量丰富。石榴酸(顺-9,反-11,顺-13-十八碳三烯酸)是一种特殊结构的脂肪酸,在植物界中相当少见。它于1935年首次被发现于安石榴(Punica granatum L.)的种子油中[5],因而得名。至今半个世纪过去,该酸仅仅在葫芦科等的二、三个属中少数的几个种的种子油中被发现有它的分布。近几年来,先后已有瓜蒌子(Trichosanthes quinquangulata A.Gray),双边栝楼(Trchosanthes uniflora Hao),大苞栝楼(Trichosanthes bracteata(Lam.) Voigt)和毛果栝楼(Trichosanthes mushaensis Hayata)四种栝楼属植物的种子油脂肪酸化学组成的研究见于国内文献的报导[2,3],在这些报导当中均没有石榴酸组成成分,其中双边栝楼,大苞栝楼和毛果栝楼被包括在我们的研究里面,我们得出不同的结果。本文报导中其余的几种,多数未见于国内外文献的报导。  相似文献   

2.
周俭民 《植物学报》2020,55(2):123-125
赤霉病是我国乃至世界小麦(Triticum aestivum)产区的重要病害, 给农业生产和人畜健康造成重大威胁。分离鉴定优质抗病基因、培育抗病品种, 是控制我国麦区赤霉病的重要手段。最近, 山东农业大学孔令让团队完成了二倍体长穗偃麦草(Thinopyrum elongatum)基因组的组装, 并在此基础上通过精细定位和图位克隆分离得到来自长穗偃麦草的抗赤霉病基因Fhb7。他们发现Fhb7编码1个谷胱甘肽转移酶, 对禾谷镰孢菌(Fusarium graminearum)分泌的包括呕吐毒素等在内的多种毒素具有解毒作用, 是1个广谱持久抗病基因。他们还发现Fhb7很可能最初源于内生真菌, 经过基因水平转移进入到偃麦草基因组中。此外, Fhb7不影响其它农艺性状, 且其抗性不受小麦遗传背景影响。这一系列工作揭示了作物抗病演化中的全新机制, 对小麦抗赤霉病育种以及更好地利用长穗偃麦草的丰富基因资源都具有重要意义。  相似文献   

3.
太原西山煤田太原组煤核中的科达植物雌性生殖器官   总被引:1,自引:0,他引:1  
报道了首次发现于我国的3种石化科达植物雌性生殖器官Cordaianthus sp.nov.,C.xishanensis sp.nov.和C.sp.,描述了它们的内部解剖构造特征,并与欧美植物区的雌性石化科达穗进行了比较,这些化石产于山西太原西山煤田太原组组上部7号煤层煤核中。  相似文献   

4.
在新疆气候生态条件下, 采用膜下滴灌植棉技术, 设置不同滴灌水分处理, 研究了不同滴灌量条件下棉花(Gossypium hirsutum)苞叶和叶片碳同化、光呼吸作用、光系统II (PSII)热耗散作用及其光破坏防御机制的差异, 以揭示滴灌节水条件下棉花苞叶缓解光抑制的机理及与棉花抗旱特性的关系。结果表明: 棉花开花后苞叶及叶片在高温强光下实际光化学效率(ΦPSII)显著降低, 发生明显的光抑制现象, 但苞叶的光抑制程度较叶片轻; 与正常滴灌量处理相比, 节水滴灌条件下棉花水分亏缺, 叶片净光合速率(Pn)、ΦPSII、光呼吸(Pr)、光化学猝灭系数(qP)降低, 非光化学猝灭系数(NPQ)升高, 叶片光抑制程度加重, 而苞叶Pn、ΦPSII、Pr、qP、NPQ变化不大, 与正常滴灌量处理相比, 光抑制程度无显著差异。苞叶光呼吸速率与光合速率的比值(Pr/Pn)显著高于叶片; 滴灌节水条件下棉花适度水分亏缺对苞叶光呼吸及Pr/Pn无显著影响。高温强光下, 棉花节水滴灌对叶片PSII量子产量的转化与分配影响显著, 但对苞叶的影响不显著; 苞叶非调节性能量耗散的量子产量(Y(NPQ))高于叶片, 因此能有效地将PSII的过剩光能以热的形式耗散。综上所述, 与叶片相比, 苞叶对轻度水分亏缺不敏感, 是棉花适应干旱逆境较强的器官, 苞叶光呼吸和热耗散作用对光破坏防御具有重要意义。  相似文献   

5.
不同小麦进化材料生育后期光合特性和产量   总被引:12,自引:0,他引:12       下载免费PDF全文
以二倍体野生一粒小麦(Triticum boeoticum)、栽培一粒小麦(T. monococcum)、节节麦(Aegilops tauschii)和黑麦(Secale cereale)、四倍体野生二粒小麦(T. dicoccoides)、栽培二粒小麦(T. dicoccum)、硬粒小麦(T. durum)、六倍体普通小麦(T. aestivum)‘扬麦9号’和‘扬麦158’及八倍体小黑麦(Triticale)为材料,采用盆栽试验研究了不同小麦进化材料生育后期旗叶光合特性的演变及产量的差异。结果表明,与六倍体普通小麦和八倍体小黑麦相比,二倍体和四倍体材料在开花前具有较高的光合速率(Pn)、气孔导度(Gs)、最大光能转换效率(Fv/Fm)和实际光化学效率(ΦPSⅡ)。开花以后,二倍体和四倍体材料受非气孔因素的影响,光合能力下降较快;除黑麦外,旗叶光合速率在开花10 d后都低于普通小麦和小黑麦,胞间CO2浓度(Ci)迅速增加,Fv/FmΦPSⅡ和叶绿素含量快速下降。二倍体和四倍体材料开花前单株总叶面积和旗叶叶面积较大,花后下降迅速,功能期短;单株穗数也较多,但穗粒数、千粒重、产量和收获指数却显著低于普通小麦。因此,小麦长期进化过程中,普通小麦花后较高的光合能力及较长的光合持续期是提高千粒重,进而提高产量的重要生理基础。  相似文献   

6.
水稻(Oryza sativa)是我国最主要的粮食作物之一, 其穗部形态直接影响着水稻产量和稻米品质。在秋光和七山占构建的重组自交系群体中发现了1个散穗突变体材料sp (spreading panicle), 田间表现为穗部一次枝梗向外延伸, 与穗轴夹角增大, 且向四周散开, 故暂命名为散穗突变体sp。与野生型相比, 突变体sp穗重、每穗粒重、千粒重、粒宽以及粒厚均极显著减少, 推测SP可能是1个参与调控穗部形态建成和颖花发育的基因。遗传分析表明, 该性状受1个显性核基因控制。利用sp与02428构建的F2群体进行基因定位, 将该基因定位在4号染色体长臂端, 位于E3和RM17578之间的62.9 kb区域内。该结果将为SP基因的图位克隆和揭示其作用机理奠定基础。  相似文献   

7.
角质层微细构造是鉴定植物属种的重要特征之一,近年来又在古气候恢复中得到广泛应用。从甘肃永昌下二叠统采获了角质层保存较好的两种科达叶化石,详细分析了表皮微细构造特征,并结合其外形特征进行了属种鉴定:其中一种鉴定为淮南科达(Cordaites huainanensis Chen),另建立了一新种,命名为永昌科达(Cordaites yongchangensis sp.nov.)。本文选取与化石标本的宏观形态和角质层微观形态较为相似的长叶竹柏(Podocarpus fleuryi Hickel)作为其现存最近对应种,初次尝试利用化石气孔特征重建了甘肃永昌早二叠世的古大气CO2浓度。  相似文献   

8.
氮作为人工草地最为重要的限制性因子, 在时间、空间上分布不均匀, 且在形态上存在差异, 与种植方式及地上净初级生产力(ANPP)存在相关关系。该研究以青海省同德牧场的无芒雀麦(Bromus inermis)、老芒麦(Elymus sibiricus)、垂穗披碱草(E. nutans)、西北羊茅(Festuca ryloviana)、中华羊茅(F. sinensis)、青海扁茎早熟禾(Poa pratensis var. anceps ‘Qinghai’)、冷地早熟禾(P. crymophila)、星星草(Puccinellia tenuiflora) 8种牧草单播人工草地为研究对象, 分析人工草地土壤可溶性氮库季节和年际动态变化过程及与ANPP之间的相互关系。该人工草地种植于2013年, 在2014-2016年(二龄、三龄和四龄)生长季6-9月测定土壤铵态氮(NH4+-N)、硝态氮(NO3--N)、可溶性有机氮(SON)和可溶性总氮(STN)含量, 每年9月初测定ANPP, 所有样地没有施肥, 每年9月中旬刈割, 留茬5 cm。研究发现: (1) 8种禾本科牧草的ANPP在329.67-794.67 g·m-2之间, 其中垂穗披碱草为794.67 g·m-2, 显著高于其他牧草。(2)在二至四龄人工草地中, 土壤NO3--N、SON和STN含量均显著下降, 但NH4+-N含量却显著增加。(3)土壤可溶性氮以SON为主, 占STN的45.11%-88.76% (0-10 cm)和47.75%-88.18% (10-20 cm); 其次为NO3--N, 占STN的5.81%-34.85% (0-10 cm)和6.08%-40.42% (10-20 cm); NH4+-N最少仅3.41%-22.18% (0-10 cm)和3.09%-19.56% (10-20 cm)。(4)非度量多维尺度分析(NMDS)结果显示, 随种植年限的增加, 不同禾本科牧草对0-10 cm土壤可溶性氮影响趋于离散, 而对10-20 cm土壤的影响则相反, 且牧草对土壤可溶性氮含量的影响程度与土壤深度有关。(5)相关性分析表明, 土壤SON、STN含量与人工草地ANPP呈正相关关系, 与无机氮(IN)含量呈负相关关系。综上所述, 三至四龄人工草地增施氮肥是维持草地生产力的关键因素。以上结果为更深入了解青藏高原人工草地土壤可溶性氮动态变化及维持人工草地生产力和稳定性提供了科学依据。  相似文献   

9.
黑龙江省林区林木鼠害危及多种树种(图1-a、b),冬季啃食幼树树皮损失严重。(舒凤梅1975、1979)。为害鼠种主要为棕背(鼠平)(Clethrionomys rufocanus),其他各种鼠为红背(鼠平)(C.rutilus)、东方田鼠(Microtus fortis)、大林姬鼠(Apodemus Peninsulae)、黑线姬鼠(A.agrarius)和花鼠(Eutamias sibiricus)。以往多采用化学药物防治。本工作发现该鼠的数量与林地郁闭度有密切关系,故而探讨了利用调整鼠类栖息环境,预防林木鼠害发生的途径。  相似文献   

10.
戴静  陈威兆  金露露  黄亮 《生物多样性》2022,30(11):22553-48
栎属(Quercus)植物叶片化石在新生代地层中分布普遍, 对亚热带常绿阔叶林具有重要的指示意义。本文对采自云南省宜良县上新统茨营组中的栎属植物叶片化石进行角质层结构分析, 结合叶形态特征, 系统描述了4种栎属植物: 阔叶栎(Quercus latifolia)线叶栎(Q. scottii)、楔基栎(Q. simulata)和黄毛青冈相似种(Q. cf. delavayi)。通过对比化石和现生植物的叶形态和角质层特征, 本文认为叶片形状、叶基和叶尖特征、二级脉数量、表皮细胞和垂周壁特征、气孔大小和形状、气孔密度、毛基类型、形态和分布情况可以作为区分不同种类的特征, 但是不能只考虑其中的一个因素, 应该综合这些特征作为判断依据。结合宜良植物群中其他化石资料认为, 包括壳斗科柯属(Lithocarpus)、栲属(Castanopsis)以及樟科、榆科、木兰科等在内的植物, 代表了以栎属青冈组为优势树种的半湿润常绿阔叶林。宜良植物群与同时期相近纬度的植物群相比, 植被类型相似, 但是落叶成分较少。宜良植物群中的线叶栎、楔基栎和阔叶栎同晚始新世的线叶栎以及早中新世的楔基栎和阔叶栎相比, 形态并未发生大的变化, 与现生植物也非常相似, 进一步说明云南现代常绿阔叶林的主要成分来自于古老植物的承袭, 没有发生较大的改变。  相似文献   

11.
Based on characters of the fertile fronds, two species of fossil ferns from the Lower Cretaceous Potomac Group of the U.S.A., originally described as species of Osmunda by Fontaine in 1889, are transferred to the genus Anemia. The two species display primitive characters for that genus. Analysis of these and other characters of Anemia and related species, using parsimony and compatibility programs, suggests possible phylogenetic arrangements and facilitates delimination of three taxonomic units within Anemia that were already distinct during Cretaceous time. The subgenera Coptophyllum and Anemia are shown to be paraphyletic in the suggested phylogenies and the schemes agree with the known stratigraphy of the fossil ferns.  相似文献   

12.
From the Oligocene Los Ahuehuetes locality, near Tepexi de Rodríguez, Puebla, Mexico, five new plant species are described based on their leaf architecture. The presence of brochidodromous or acrodromous venation, and secondary veins forming angular (versus rounded) arcs, are well defined characters in the fossil material that relate it to Berberidaceae. Comparison with the leaves and leaflets of extant and fossil plants allow the recognition of one Mahonia and four Berberis new species. The lack of detailed information on leaf architecture in Berberidaceae limits the evaluation of the taxonomic relationships that can be suggested between fossil and extant plants. However, from a biogeographic point of view the presence of these new fossil plants supports the hypothesis of a North American origin of the Orientalis Groups of Mahonia, to which a lineage of Berberis may be added. Furthermore, two of the new species suggest the dispersal, some time during the Tertiary, of a lineage that today forms the Australis Group of Berberis from low latitude North America to South America. The movement of the Chortis Block is proposed as an alternative to explain the dispersal of a growing list of plants from north to south in the Americas. Only through future geological and palaeobotanical work can this hypothesis be corroborated.  相似文献   

13.
描述了产自新疆克拉玛依吐孜沟下侏罗统八道湾组的古蝉科化石3新种,即plachutellaexculptasp.nov,Fletcherianajurassicasp.nov.和Pseudocossusstrenussp.nov。这是古蝉科在我国西北地区的首次发现。八十年代以来,古蝉科在我国华北和东北地区被陆续发现,但其中一些种类在分类上存在一些问题,笔者对此作了修正,并对有蝉科在我国的地质、地理分布作了回顾。  相似文献   

14.
Abstract Three new species of fossil insects described here were collected from the Lower Jurassic Badaowan Formation of Tuzigou, Karamai, Xinjiang of northwestern China and are respectively referred to three genera of Palaeontinidae. They are Fletcheriana jurassica sp. nov., Plachutella exculpta sp. nov., and Pseudocossus strenus sp. nov. Some insects of Palaeontinidae have been in discovered succession in northern China. But it should be pointed out that in classification of some of these insects, there exist many questions, which are discussed here. The geological and geographical distributions of Palaeontinidae in China are reviewed in this paper.  相似文献   

15.
广西百色盆地更新世樟科两种植物角质层研究   总被引:3,自引:0,他引:3  
本文描述的具角质层的两块叶化石,产自广西百色盆地更新统长蛇岭组。经与现代植物的角质层对比研究后,确定这两块叶化石分属于樟科的两属两种,即油丹(近似种)(Alseoda-phne cf.hainanensis Merr.)和紫楠(近似种)[Phoebe cf.sheareri(Hemsl.)Gamble]。研究结果表明,角质层在鉴定被子植物化石中具有可靠的价值。  相似文献   

16.
A section in the Late Pleistocene Port Morant Formation of Jamaica shows a progradational deltaic succession passing from offshore muddy sands, through shoreface to foreshore deposits. The transition zone/lower shoreface has abundant Ophiomorpha burrows and contains common examples of the echinoid Leodia cf. sexiesperforata (Leske). Modern Leodia occur in shallow marine carbonate sands, and the Port Morant occurrence is the first record of abundant Leodia in the geological record. Despite their strong test construction that should give Leodia a high preservation potential, these echinoids have a poor fossil record because the environments in which they lived are rarely preserved. Consequently, the fossil record is biased towards species that occur in environments with high preservation potential.  相似文献   

17.
Ch. E. Weiss established the genus Palaeostachya in 1876, This genus represents the strobilus of Calamites. As a kind of reproductive organ, the Palaeostachya was first proposed to name Volkmannia by Sternberg but later had been renamed to Palaeostachya by Weiss (1876). In this paper two new species of Palaeostachya, Palaeostachya plagiobracteata sp. nov. and Palaeostachya densibrateata sp. nov., were collected from Lower Shihhotse formarion of Taiyuan in Shanxi Province, and they are described here. Palaeostachya plagiobracteata sp. nov. is a very interesting strobilus, of which both basal and upper parts are not preserved. The specimen of the strobilus is about 2.5 cm long and 1.2 cm in the greatest dismeter. Bracts which extend horizontally from the axis and then turn upward are well preserved. Two rows of them are rather conspicuously. Bract is about 4 mm. long, upper part is about 1 mm. Axis is about 2 mm in width. Four rows of sporangia are distinctly around the axis. The sporangia are sessile, rather large, oblong-ovate in shape, and attach directly to the basal part of bract in an axillary position. Horizon and Locality: Lower Shihhotse formation. Tungshan, Taiyuan, Shanxi. Palaeostachya densibracteata sp. nov. is an important strobilus, of which basal and tip parts are very well preserved. The basal part of sterigma of strobilus is preserved. There are many lepidosomes on the sterigma. Lepidosome is about 3 mm in width and its tip is well preserved. Strobilus is similar to ear of corn in shape about 3 cm long, 1.5 cm. in width. Bracts are well preserved. Six rows of them are more conspicuously in the specimen. The bracts extend horizontally from the axis and then turn upward nearly parallel with the axis. The tip part of each bract appears short triangle, but basal part is contiguous. Sporangia are not preserved in the specimen. Horizon and Locality: Lower Shihhotse formation; Tungshan, Taiyuan, Shanxi.  相似文献   

18.
苏北盆地阜宁组钙质超微化石由来初探   总被引:4,自引:0,他引:4  
对苏北盆地4个钻孔300余块心样品进行了分析,在阜宁组的8块样品中发现了钙质超微化石,计3属1种及3个比较种,化石属种单调,保存较 ,受到严重的溶蚀或增生,结合这些种类的分布时代和产出层位,很难排除苏北盆地阜宁组钙质超微化石再沉积的属性。  相似文献   

19.
The first fossil desmodontine record and the only well documented chiropteran fossil record from Argentina is described. A complete left upper canine was collected at Centinela del Mar (38°21′S58°W, General Alvarado County, Buenos Aires Province) from fossil-bearing sediments referred to the Late Holocene. The tooth size is 25% larger than that of the modern vampire bat, Desmodus rotundus. We assign this tooth to Desmodus cf. D. draculae, an extinct species recorded in the Pleistocene–Holocene of South America (Brazil and Venezuela). The southernmost distribution of present-day Desmodus extends to northeast Buenos Aires province (35°S). The presence of Desmodus some 600 km south of this present-day limit (July minimal isotherm of 10°C) indicates that around 300 years BP the southeastern Buenos Aires province was at least 2°C higher than modern July isotherm. The Desmodus tooth is associated with sigmodontine rodents characteristic of subtropical and temperate-warm areas (e. g., Pseudoryzomys simplex, Bibimys cf. B. torresi), and provides additional evidence to support this hypothesis. A correlation with a global warming phase is discussed.  相似文献   

20.
This paper deals with the Fossil Plants from Upper Permian in Northern Xinjiang. These plants include 25 species of 15 Genus. Five new species is all described in this paper. These are: ?Supaia serrata sp. nov. Tychtopteris densinervis sp. nov., Ty. obesa sp. nov., Comia Cangfanggouensis sp. nov. and Lepeophyllum ovatum sp. nov. These are all new to science, found in the Lower Cangfanggou Group in Northern Xinjian, of Late Permian in age. Some fossils Lobatannularia multifolia Ken'no, Sphenopteris rotunda Sze and Alethopteris huiana Lee found in this group are known in the Cathaysian Flora. Others are common in the Angara Flora, such as Stellotheca sehtchurowskii (Schmal.) Surange et Prakash, Sphenopteris, adzvensis Zal., Tychtopteris cuneata (Schmal.) Zal. Noeggerathiopsis sp., ect. That indicates in the Lower Cangfanggou Group is a transitional zone between the Angara and the Cathaysian floras.  相似文献   

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