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1.
中国鸢尾属花粉形态研究   总被引:12,自引:1,他引:11  
本文借助光学显微镜和扫描电镜,对我国产鸢尾属Iris L.32种植物的花粉形态进行 了观察。该属植物的花粉为舟形或近球形。萌发孔可分为远极单沟、远极单沟-拟沟、二合 沟及无萌发孔等类型。外壁主要为网状纹饰,少数具瘤状或鼓槌状纹饰。本文依据花粉形态 和其它器官特征,对本属花粉外壁及萌发孔的演化趋势及某些种的分类地位进行了探讨。  相似文献   

2.
中国紫草科破布木属花粉形态和外壁超微结构   总被引:11,自引:0,他引:11  
为了深入探讨紫草科(Boraginaceae)的分类问题,用光学显微镜和扫描电子显微镜观察了该科破布木属(CordiaL.) 10种植物的花粉形态和外壁超微结构。发现该属花粉具三孔、三孔沟、三拟孔沟和三合沟4种萌发孔类型。外壁表面具微刺状纹饰、刺状纹饰、网状纹饰和不规则的条纹网状纹状。破布木属的花粉特征表明,该属花粉在紫草科中既是独特的分类群,又是比较原始的属种。  相似文献   

3.
用扫描电子显微镜对中国鸡矢藤属(Paederia L.)6种1变种植物的花粉进行观察。结果表明:鸡矢藤属植物的花粉均为单粒,辐射对称,小型或中型,极面观3-裂圆形至钝三角形,赤道面观呈长圆球形或近长球形,具3个萌发沟,无内萌发孔。外壁纹饰网状、细网状或穿孔状,孔边缘具小刺状突起或无。臭鸡矢藤(P.foetida)和白毛鸡矢藤(P.pertomentosa)具有花粉二型现象,其中白毛鸡矢藤(P.pertomentosa)是首次报道。花粉二型现象与花柱二型现象可能没有直接的关联性,与前人的观点一致。推测鸡矢藤属外壁纹饰的可能演化趋势为:穿孔、网状、细网状→粗网状;网眼内无棒状突起→网眼内有棒状突起。鸡矢藤属花粉的外壁纹饰变化较大,且无内萌发孔,是茜草科花粉过渡类型的特征。  相似文献   

4.
中国菟丝子属植物花粉的扫描电镜观察   总被引:2,自引:0,他引:2  
张芝玉  郭澄  苏中武  李承祜   《广西植物》1991,11(4):308-311+393
本文作者用扫描电镜(SEM)对国产菟丝子属(Cuscuta L.)10种植物的花粉形态进行了观察。具3沟萌发孔的花粉为本属基本类型。根据萌发孔的数目,外壁纹饰等特征,该属花粉可划分为三个类型:(1)具3沟,外壁具穿孔,表面散生小刺状突起;(2)具3—5沟,外壁具网状纹饰,网脊上散生小刺状突起;(3)具3—6沟,外壁具小刺状突起,穿孔偶见。本文观察结果与刘炳仑等曾报道过光学显微镜(LM)下的结果不完全一致。最后,对菟丝子属的花粉形态的演化趋势以及属内亚属间关系进行了讨论。  相似文献   

5.
重楼属花粉形态的研究   总被引:4,自引:1,他引:3  
本文对重楼属(paris L.)18个种和变种或变型的花粉形态进行了光学显微镜和电镜的观察和初步比较研究。就所观察过的种类看,花粉粒为扁球形,极面观椭圆形。左右对称。具一远极沟。外壁两层,外层厚于或等于内层。外壁纹饰有穴状、网状和皱-网状之分。不同的种类,其花粉大小和外壁纹饰均或多或少有所不同,其中有些种类的外壁纹饰比较特殊,可以作为区分种类甚至作为分组的依据或参考。  相似文献   

6.
水雍科植物的花粉形态研究   总被引:1,自引:0,他引:1  
孙坤  陈家宽  张志耘 《植物研究》2002,22(1):T001-T002
应用光学显微镜、扫描电镜和透射电镜对世界水雍科6种植物的花粉形态进行了观察。水雍科植物花粉为舟形或船形,具远极单沟萌发孔类型,外壁纹饰通常为浅网状至网状,稀为小刺状纹饰,外壁外层由覆盖层、柱状层和基层组成,覆盖层厚。水雍科植物花粉外壁纹饰表现了从小刺状向网状的过渡。该科花粉为远极单沟,覆盖层厚,具小刺等特征反映了其与水鳖科和泽泻目花蔺科的密切联系,而该科花粉外壁纹饰多为网状则与茨藻目植物接近。这一结果支持将水雍科从茨藻目中分出作为一个独立的目处理的观点。此外,水雍科植物的花粉大小、纹饰类型、网眼大小与深浅等方面的差异对种级分类有一定意义。  相似文献   

7.
利用光学显微镜和扫描电镜研究了茜草科粗叶木属Lasianthus 16种2亚种、1变种及相关的5属5种的花粉形态。粗叶木属的花粉属于广孢型, 单粒。一般中等大小, 绝大多数为圆球形, 少数为近长球形或长球形。花粉形态特征, 特别是在萌发孔和外壁纹饰上表现出多样化。根据孔沟的数目或是否具有内孔, 可以将萌发孔分为(3-)4-(-5)孔沟和3孔。在所观察的这些种中, 萌发孔以3-4孔沟为主要类型, 比例为62.4%。外壁纹饰可分为细网状、粗网状和穴状。有部分种的花粉极面有穴状纹饰, 其余均为网状纹饰。网眼一般椭圆形、近圆形、三角形或者不规则形。少数外壁纹饰网脊上有颗粒状雕纹或模糊的颗粒, 网脊轮廓线呈波浪形, 一般凸出且平滑。大部分种的花粉具有沟膜, 沟膜上具有瘤状突起或小颗粒状, 沟边缘一般较平滑, 或粗糙, 有的种具有沟桥。  相似文献   

8.
中国钩藤属9种植物的花粉形态   总被引:1,自引:0,他引:1  
利用光学显微镜和扫描电镜对中国钩藤属(Uncaria Schreb)9种植物的花粉形态进行了观察.结果表明,钩藤属植物的花粉为单粒,小型,辐射对称,赤道面观圆球形至近长球形,极面观3-裂圆形,具3孔沟,萌发沟裂缝状,长达两极.萌发沟中央有"内壁加厚突出"结构.外壁具条纹至细网纹饰,表面光滑无附属物.钩藤属花粉大小、形状、萌发沟和纹饰类型都较接近,属于单一型花粉.钩藤属植物的花粉形态特征是茜草科(Rubiaceae)中较为原始的类型.  相似文献   

9.
对国产荚蒾属Viburnum Linn.植物花粉的光学显微镜及扫描电镜观察表明:1.花粉特征在组间的分类学意义不大,而在组内的每一种都具各自的花粉特征。2.表面纹饰类型包括(1)外壁具半覆盖层,网状纹饰,网脊光滑;(2)外壁具半覆盖层,网状纹饰,网脊上具瘤状突起;(3)外壁无覆盖层或部分成半覆盖层,具鼓锤状基柱或基柱网,基柱顶端具瘤状突起。3.沟类型包括:(1)沟沿处外壁无覆盖层;(2)沟沿处外壁具半覆盖层,网状纹饰;(3)沟沿处外壁具覆盖层;(4)在一极形成合沟。内孔类型包括(1)看不见明显的孔膜;(2)孔膜半球状,与外壁不连续;(3)孔膜半球状,与外壁相连续;(4)孔膜半椭圆球状,纵长;(5)孔膜半椭圆球状,横架于沟间而类似于桥。文中同时对若干组内分类学问题进行了探讨。  相似文献   

10.
豹子花属的花粉形态研究,兼论与百合属的界限问题   总被引:12,自引:3,他引:9  
本文借助光学显微镜和扫描电镜,对豹子花属Nomocharis 6种植物和百合属Lilium 4 种植物的花粉形态与外部特征作了较系统的比较研究,其结果如下: 1.豹子花属植物花粉的 萌发孔均为单沟(远极)型,根据其外壁结构及表面纹饰的特点,可分为基柱网纹型和网纹 型,结合外部形态特征推断,可能存在由基柱网纹→网纹的进化趋势。 2.百合属植物花粉 的萌发孔多为单沟(远极)型,稀为2一3孔型,然而,其中外部形态极为相近的小百合集合群与 尖被百合在花粉形态上表现出较大的差异,这一事实为研究百合科花粉的演化提供了线索。豹 子花属与百合属花粉虽在表面纹饰上存在区别,但从外部形态上,该属的一些种类与百合属极 为相近,反映出二属之间存在着较为紧密的亲缘关系。  相似文献   

11.
In this work examined were pollen grains of 6 species of Nomocharis and 4 species of Lilium, all under LM and SEM, but Nomocharis saluenensis Balf. f. under TEM. The pollen grains are monocolpate (distal) in Nomocharis, monocolpate or 2-3-porate in the species of Lilium examined. Two types of pollen grains in Nomocharis are recognized based upon the exine stratification and sculpture. The pollen characters and gross morphology, and their evolutionary trends in both Nomocharis and Lilium are discussed. Our conclusions are as follows: 1. Lilium henrici Franch. 、L. souliei (Franch.) Sealy 、L. lophophorum (Bur. et Franch.) Franch. and L. nanum Klotz. et Garcke differ from Nomocharis in the aperture and sculpturing elements. Their pollen morphology supports their being placed in Lilium. 2. The pollen grains of both Lilium lophophorum (Bur. et Franch.) Franch. and L. nanum aggregate are monocolpate or 2-3-porate, which shows an evolutionary trend of aperture from monocolpate to porate, as suggested by Walker and others [Walker et al., (1975), and Chanda (1979)]. 3. In Balfour’s (1918) classification system of Nomocharis, N. pardanthina Franch. and N. meleagrina Franch. belong to Sect. Nomocharis, while N. forrestii and N. biluoensis are placed in Sect. Ecristata, but their pollen grains are all reticulate. They refer to type I (see Table 2). Thus, it does not seem reasonable placing in a single section, Sect. Ecristata, N. forrestii and N. biluoensis with the reticulate exine and N. saluenensis and N. aperta with the two-row-ritipilate exine. 4. Nomocharis saluenensis Balf. f. differs from Lilium in the exine sculpture, which seems to support placing it in Nomocharis. 5. Muri of N. forrestii Balf f. and N. biluoensis s.y. Liang show a tendency of connecting each other by heads of pili, and these two species are intergraded with the other species of the type I with respect to gross morphorlogical characters. It is thus considered that the reticulate pollen grains in Nomocharis is derived from ritipilate ones. This opinion is also held by Nair (1965). 6. Nomocharis differs from Lilium in the exine ornamentation, but some species of Nomocharis are very similar to Lilium in the gross morphology. It shows the close affinity between Nomocharis and Lilium.  相似文献   

12.
蜘蛛抱蛋亚族的花粉形态   总被引:6,自引:0,他引:6  
本文研究并报道了百合科蜘蛛抱蛋亚族的花粉形态,主要结论如下:1.开口箭属含两种花粉类型即:(1)单槽、椭圆形;(2)无萌发孔、球形。具单槽、椭圆形花粉的种类含单型性核型,花形较小,柱头小而花柱短,雄蕊高于柱头;无萌发孔、球形花粉的种类则为单型性核型,花形较大,柱头常高度膨大,雄蕊常着生在花被筒基部。2.万年青属花粉为椭圆形,具单槽;蜘蛛抱蛋属花粉则为球形,无萌发孔;开口箭属花粉一部分与万年青属相似,另一部分则与蜘蛛抱蛋属雷同。3.蜘蛛抱蛋亚族中最原始的花粉类型为单槽椭圆形,具孔状或网状外壁纹饰。球形,无萌发孔,外壁具皱波状、瘤状或芽孢状纹饰的花粉为派生类型。4.蜘蛛抱蛋亚族种下花粉形状、萌发孔类型和外壁纹饰基本稳定,可作为分种特征。  相似文献   

13.
Pollen morphology in the subtribe Aspidistrinae is reported and the main viewpoints are summarized as follows: (1) Two major types of pollen grains, i.e., monosulcate,ellipsoidal pollen and inaperturate, spheroidal pollen, are identified in the genus Tupistra. The species with monosulcate, ellipsoidal pollen usually have monomodal karyotypes, brightcolored flower, smaller stigma, and stamens inserted at upper or middle part of perianth tube, while the inaperturate and spheroidal pollen is always found in the species with bimodal karyotypes, dingy-colored flower, swollen stigma and stamens inserted at the base of perianth tube. (2) Pollen grains in the genus Rhodea are monosulcate and ellipsoidal, while those in the genus Aspidistra are inaperturate and spheroidal, correspondingly similar to the second type of pollen grains in the genus Tupistra. (3) The most primitive pollen in the subtribe Aspidistinae is regarded as monosulcate and ellipsoidal, having perforate or reticulate exine sculpture. The inaperturate, spheroidal pollen with verrucate, gemmate or rugulate exine sculpture is considered derived; (4) Unlike those reported in other groups of the family Liliaceae, the infraspecific pollen shape, aperture type and exine sculpture in Aspidistrinae are basically stable and may serve as a taxonomic character.  相似文献   

14.
Pollen morphology was examined in 40 samples from 19 species in the genus Erythronium (Liliaceae) using scanning (SEM) and transmission electron microscopy (TEM). Pollen grains are monosulcate monads, except for a plant of E. oregonum which has dyad grains. North American and European species are characterized by reticulate exine sculpture composed of various degrees of wavy muri and variably-sized lumina. The most distinctive feature of exine sculpture in the genus is exhibited by the Asian species E. japonicum, which has a unique reticulate pattern composed of striate muri and a distinctive exine structure without columellae. The distinctness of E. japonicum pollen suggests that it has specialized in isolation from species in North America and Europe.  相似文献   

15.
国产山龙眼科花粉形态及外壁超微结构的研究   总被引:1,自引:1,他引:0  
  相似文献   

16.
The pollen morphology of 9 species of Paeonia L. has been investigated with both light microscope and scanning electron microscope. In addition, the exine structure of pollen grains of Paeonia suffruticosa and P. lactiflora was examined by transmission electron microscope. Tricolporoidate aperture is an important character of the pollen grains of the Paeonia. The surface of the exine is characterized by reticulate, foveolate and irregularly tuberculate-foveolate sculpture under the SEM. Thin sections of the pollen of this genus shows that the layers of exine are complete i.e. a perforate rectum to semitectum, columellae and foot layers. The endexine is continuous, considerably thickened in the aperture areas and relatively thin or indistinct in the mesocolpia. Paeonia has been placed in Ranunculaceae. But since the beginning of this century many authors have suggested to separating Paeonia from Ranunculaceae. Pollen marphology supports such separation. In Ranunculaceae most pollen grains are tricolpate or have other types of aperture, and exine with spinules and perforations between them. In electron microscopy, the ektexine contains a foot layer, columellae, and perforate rectum, the columellar layer with two types of columellae; the endexine is generally thin. However, the columellar layer of Paeonia has only monomorphic columellae. Some authors considered that there is a close relationship between Paeonia and the Dilleniaceae, but these also differ in the characters of the pollen grains. In Paeonia the constriction of the colpus in equator is in some degree similar to that of Theaceae (Camellia sasanqua Thunb.), Guttiferae (Hypericum L.), Actinidiaceae and Rosaceae. But in the other respects they are quite different. In sum, the pollen morphology of Paeonia is unique. So the palynological information supports Takhtajan's view that Paeonia should be elevated to a family (Paeoniaceae) or order (Paeoniales).  相似文献   

17.
Pollen morphology of 25 Chinese species, representing 6 five genera in the tribe Rhamneae of Rhamnaceae, was examined under LM and SEM. Pollen grains are subspheroidal or suboblate, obtuse-triangular in polar view, 3-colporate, with the polar axis (P)10.4-28.7μm long and equatorial axis (E) 11.3-30.5μm long, P/E = 0.81-1.11. Colpi generally narrow and long, ora lalongate, with two ends connected with the thinned part of exine, forming a H-shape. Four thickenings were observed where colpi and ora cross, but sometimes the thickenings were indistinct or formed a ring. The stratification indistinct. The ornamentation of exine obscure or indistinctly reticulate under LM, but rugulose, short-striate, rugulose-foveolate or reticulate under SEM. The exine ultrastructure of Rhamnus ussuriensis was examined under TEM. It consists of imperforate tectum, granular layer, foot layer and endexine. The tectum is rather thick with uneven surface, while the granular layer is rather thin. A key to the genera based on pollen characteristics is provided and the general pollenmorphology of five genera, i.e. Sageretia, Rhamnus, Hovenia, Colubrina and Alphitonia, is described respectively. Based on pollen size, the four thickenings and the ornamentation, the five genera under study may be distinguished from each other. For example, pollen grains are smaller in Sageretia; the four thickenings are larger and distinct in Hovenia and Alphitonia. However, the ornamentation is short-striate under SEM in Hovenia and Alphitonia, while reticulate in the Colubrina and Rhamnus ( Subgen. Rhamnus) .Two different concepts of Rhamnus exist among taxonomists. Heppeler and Suessenguth divided Rhamnus into two subgenera (Subgen. Frangula and Subgen. Rhamnus), whereas Grubov separated Subgen. Frangula from Rhamnus as an independent genus. According to the pollen morphology, the separationis reasonable.  相似文献   

18.
The pollen morphology of 28 species of Parnassia L. was investigated with light microscopy and scanning electron microscopy (SEM). The shape of pollen grains in this genus varies from subspheroidal to prolate in equatorial view and is three-lobed circular in the polar view. Pollen grains are usually radially symmetrical, isopolar, tricolporate or syntricolporate, with reticulate sculpture. The pollen characteristics among species are fairly similar to each other. Morphological information regarding the pollen grains shows that Parnassia is a natural genus. Based on exine ornamentation observed under SEM, three types of pollen grains were recognized: (i) type I, with foveolate-reticulate sculpture; (ii) type II, with a finely reticulate sculpture; and (iii) type III, with a coarsely reticulate sculpture. Most sections of this genus have one type of sculpture of pollen morphology, but Sect. Nectarotrilobos has three types of sculpture and Sect.Saxifragastrum has two types of sculpture. All three types of sculpture can be found in Southwest China,with species with the longest (Parnassia delavayi Franch.) and shortest (Parnassiafaberi Oliv.) colpi,implying that Southwest China is the center of diversification of the genus.  相似文献   

19.
中国紫葳科花粉形态的研究   总被引:2,自引:1,他引:1  
对紫葳科18属27种花粉进行了光镜和扫描电镜的观察,其中有些种是第一次观察或报道。紫葳科花粉明显地属多型花粉,萌发孔类型和纹饰特征多种多样。萌发孔基本上可分为3(-4)沟,3(-4)孔沟,3孔,多沟及散沟等类型;纹饰则可分为皱波状饰,穴状纹饰,穴-网状纹饰,网状纹饰,刺状纹饰以及表面光滑等。值得注意的是在菜豆树属Rademoachera Zoll.et Moritzi中,菜豆树R.sinica和滇菜豆树R.yunnanensis虽为同一个属,但其萌发孔类型和纹饰特征截然不同,菜豆树花粉为3孔,具网状纹饰;而滇菜豆树花粉为3孔沟,具穴状纹饰。就花粉形态学而言,紫葳科也许是多元发生的。  相似文献   

20.
The present paper reports the pollen morphology of 36 species and varieties of Brassica L. in China mostly for the first time. They were examined both under LM and SEM. Pollen grains of Brassica L. in China are long-spheroidal, subspheroidal, spheriodal, oblate, rarely reniformis or subsquare. According to the aperture characters pollen grains may be divided into four types: 2,3,4-colpate, 3-colpate, 3,4-colpate, 3,4-colporate. The exine sculpture may also be divided into three types: 1, reticulate, 2, cerebroid-reticulate, 3, foveolatereticulate. Detailed characters of pollen grains for each taxon are presented in Table 1. The 2,3,4-colpate type of pollen grains may be considered as primitive one and the 3,4-colpate or 3,4-colporate type of pollen grains is the most advanced in Brassica. The tricolpate aperture and reticulate exine have been reported by the previous authors, whereas, 3,4-colporate and cerebroid-reticulate or foveolate-reticulate pollen grains are newly reported.  相似文献   

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