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1.
东北杜鹃花科4属植物花粉形态的研究   总被引:4,自引:0,他引:4  
利用光学显微镜和扫描电子显微镜对东北杜鹃花科甸杜属(Chamaedaphne Moench.)、杜香属(Ledum Linn.)、松毛翠属(Phyllodoce Salisb.)、越橘属(Vaccinium Linn.)4属6种, 1变种的花粉形态进行了观察和比较研究。以上4属花粉粒均为四合花粉。四合花粉呈正四面体排列。花粉粒近球形。每粒花粉均具3沟,在四合花粉粒上,相邻花粉粒上的沟相接,有些种可见沟内的萌发孔。光镜下可见花粉外壁为内外两层,厚度约相等。不同属种的花粉粒在大小上有区别,花粉粒平均直径为34.0~43.7μm。在扫描电镜下观察可见不同的种花粉表面具有不同的纹饰。为分类学提供了孢粉学方面的证据。  相似文献   

2.
Pollen grains of six species of Gnetum , G. parvifolium , G. hainanense , G. luofuense , G. pendulum , G. cleistostachyum and G. montanum , collected from China were examined using light, scanning and transmission electron microscopy. Pollen grains of Gnetum are subspheroidal or irregular-apolar, inaperturate, 11.21–22.44 µm in long axis and 9.34–20.47 µm in short axis. The exine surface is covered with spinules, 0.50(0.30–0.71) µm long spaced on average 1.12(0.81–1.46) µm apart. The exine is about 0.55 µm thick and comprises ectexine and endexine. The ectexine includes a thin tectum and an infratectal granular layer. The tectum protrudes outwards, forming the spinules. The endexine is composed of discontinuous lamellae, with lacunae between lamellae. The pollen grains of Gnetum are compared with those of Ephedra and Welwitschia , and also those of the ANITA Group of angiosperms, including Amborellaceae, Nymphaeales, Illiciales, Trimeniaceae and Austrobaileyaceae. The exine ultrastructures of Gnetum , Ephedra and Welwitschia are quite similar, consisting of tectum, granular layer and lamellated endexine. The exine ultrastructure of Gnetum is also similar to that of Nymphaea colorata (Nymphaeaceae) in the transitional region between the proximal and distal poles, but differs from that of Amborellaceae, Illicium religiosum (Illiciaceae), Schisandra (Schisandraceae), Trimeniaceae and Austrobaileyaceae. This comparison of exine ultrastructure provides new evidence for consideration of the relationship between Gnetum and the ANITA Group.  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 415–425.  相似文献   

3.
东北杜鹃花属植物花粉形态的研究   总被引:9,自引:0,他引:9  
利用光学显微镜和扫描电子显微镜对东北杜鹃花属(Rhododendron Linn.)6种, 1变种, 1变型的花粉形态进行了观察和比较研究。该属花粉粒均为四合花粉。四合花粉呈正四面体排列。花粉粒近球形。每粒花粉均具3沟,在四合花粉粒上,相邻花粉粒上的沟相接,有些种可见沟内的萌发孔。光镜下可见花粉外壁为内外两层,厚度约相等。不同的种在花粉粒大小上有区别。在扫描电镜下观察可见不同的种花粉表面具有不同的纹饰。即该属在花粉形态上具有种的特性。  相似文献   

4.
V. N Kosenko 《Grana》2013,52(1):20-30
Pollen of 34 species from 7 genera of the Liliaceae were examined by LM and SEM with respect to the taxonomy of the family. Detailed pollen­morphological characteristics are given for all genera in the family on the basis of the results presented here together with data from the literature. The genera Tulipa and Lilium are heterogeneous in both aperture type and exine ornamentation. Pollen of Tulipa is monosulcate, 3-aperturate or inaperturate, with a microreticulate-striate, reticulate-implecto-striate, scabrate, perforate-rugulate, perforate-striate exine surface. Pollen of Lilium is monosulcate and 3-porate with a macroreticulate exine. The other genera are homogeneous in possessing of single longitudinal aperture (type monosulcate). The pattern of exine ornamentation and the structure of the aperture and its membrane are peculiar features for species and genera. Pollen of Erythronium and Tulipa are occasionally operculate, while in other representatives of the Liliaceae an operculum is lacking. Pollen morphological data support the division of the family into 3 tribes, namely Lloydieae, Lilieae, and Tulipeae.  相似文献   

5.
Agonistic sounds of two pomacentrid species, Plectroglyphidodon lacrymatus and Dascyllus aruanus , were recorded in captivity. Plectroglyphidodon lacrymatus produced trains of 2–5 pops, each composed of 18–25 cycles, with an average duration of 56 ms; most energy ranged from c. 100 to 1000 Hz. Dascyllus aruanus produced pops and chirps. Pops were generally composed of a single pulse, with 2–14 peaks and an average duration of 6·7 ms. Pops contained energy >4 kHz, and peak frequency ranged from 680 to 1300 Hz. Chirps consisted of trains of 12–42 short pulses of three to six cycles, with durations varying from 0·6 to 1·27 ms; peak frequency varied from 3400 to 4100 Hz. Sound production in P. lacrymatus suggested that pomacentrids are derived from an ancestral taxon capable of sound production and that this capacity is a synapomorphy for the family. Although in the Pomacentridae, pops are typically composed of a single pulse, which is longer and higher pitched than chirps composed of a series of shorter pulses, D. aruanus chirps were higher pitched than its pops. Thus, acoustic variation in the genus Dascyllus is probably not more restricted than in the Pomacentridae.  相似文献   

6.
7.
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   

8.
Pollen morphology can be useful in the determination of phylogeny and mating systems of plants. Pollen ovule ratios can give an indication of the mating system of plant species, and there are a number of theories as to reductions in response to pollination strategies. Pollen tetrad segregation occurs when a number of pollen grains within a tetrad abort; this process has evolved a number of times in the family Ericaceae. Pollen ovule ratios along with the total number of tetrads, number of viable grains and proportions of each of the tetrad types were investigated in six species of Acrotriche (Styphelioideae: Ericaceae). Pollen ovule ratios were used in comparison with related species to give indications of mating systems and to examine theories regarding reductions in pollen production. The study species can be arranged into distinct groupings based on the proportions of tetrad types that correlate with floral morphology and may be indicative of phylogentic associations.  相似文献   

9.
报道了国产爵床科Acanthaceae山牵牛属Thunbergia(山牵牛亚科Thunbergioideae)6种、叉柱花属Staurogyne(瘤子草亚科Nelsonioideae)和老鼠簕属Acanthus(老鼠簕亚科Acanthoideae)各1种植物在扫描电镜下的花粉形态。山牵牛属植物的花粉粒为圆球形,均具螺旋状萌发孔,外壁纹饰以光滑或颗粒状为主,偶具棒状突起。具螺旋状萌发孔被认为是该科独特而较原始的花粉特征。叉柱花属的花粉粒为圆球形,具3孔沟,外壁平滑。老鼠簕属的花粉粒为长球形,具3沟,外壁具细网状纹饰或具小穿孔。花粉形态特征支持传统上将上述3属置于3个不同亚科的处理。  相似文献   

10.
A survey of pollen morphology in 20 species representing the 11 genera of the North American subtribe Stephanomeriinae by light, scanning electron, and transmission electron microscopy revealed 10 of the 11 genera to have echinate, tricolporate pollen grains, Lygodesmia being the only genus with echinolophate pollen. Sectioned exines of most of the species examined are similar, being composed of ektexine and endexine. The ektexine surface is composed of spines which typically have globose perforate bases. A cavus occurs as a separation between the basis (foot layer) and the columellae in all of the genera examined except Chaetadelpha. Pollen of the two species of Glyptopleura were found to be strikingly different in exomorphology. Pollen of the putatively self-fertile G. marginata has much shorter spines than the closely related G. setulosa. Atrichoseris, Anisocoma, Calycoseris, Glyptopleura, Pinaropappus, Prenanthella, and most species of Malacothrix have pollen which lack paraporal ridges. The remaining genera, Chaetadelpha, Lygodesmia, Rafinesquia, and Stephanomeria have well-developed ridges of fused spine bases around the apertures. Pollen characters, particularly those of the aperture region, have been found to be systematically useful in the subtribe, therefore acetolyzed material gives more useful information than untreated pollen.  相似文献   

11.
Schaueria calycobractea, a new species of Acanthaceae from Mexico and a genus new to the Mexican flora is described. Pollen morphology of the new species is discussed with reference to generic and tribal concepts in the family.  相似文献   

12.
Pollen morphology has been extensively studied in the Arecaceae, and pollen aperture organization is usually distal monosulcate, as in many monocot families. Much is known about the influence of microsporogenesis on aperture configuration, but the key processes during microsporogenesis responsible for aperture type, number and arrangement are still poorly understood. In order to clarify the developmental sequence underlying aperture type and organization in palm monosulcate pollen, a study of the characteristics of male postmeiotic development was carried out in representative species of four genera of subfamily Coryphoideae, and four genera of subfamily Arecoideae. We found evidence for the occurrence of successive cytokinesis in addition to simultaneous cytokinesis in three Coryphoideae species. Tetrad shape was highly diverse within all species. Our results reveal an unexpected diversity in microsporogenesis from which it may be possible to gain further insight into pollen evolution within the family.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 93–102.  相似文献   

13.
This paper adds new data on the pollen and orbicule morphology of 61 Dioscorea L. (Dioscoreaceae) species to the survey of Schols et al . (2001). The results indicate that pollen characters may be significant in infrageneric systematics in Dioscorea . Pollen and orbicule characters are described based on observations with light microscopy, and scanning and transmission electron microscopy, and are critically evaluated and discussed in the context of existing hypotheses of systematic relationships within the genus. Pollen is mostly disulculate (sometimes monosulcate) with a perforate, microreticulate, striate, gemmate, rugulate, or cerebroid perforate sexine. The basal section Stenophora is one of the few sections with monosulcate pollen. Brachyandra , Cardiocapsa , and Seriflorae , three Malagasy sections, are characterized by striate pollen. Pollen morphology strongly supports section Enantiophyllum as a monophyletic group. The correlation between pollen size and tuber type, as suggested previously by P. Su (1987), is confirmed by our data. As found in our earlier survey, orbicules in Dioscorea are mostly spherical with a smooth or spinulose surface.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 143 , 375–390.  相似文献   

14.
Pollen morphology of 89 species and 3 varieties belonging to 18 genera (out of 150 spcies in 20 genera) of Zingiberaceae in China was studied under both light microscope and scanning electron microscope. Pollen grains of Zingiberaceae are spherical, subspherical, ovoid and prolate, 36-225 μm in size, nonaperturate or aperturate (spiraperturate, porate). Pollen grains are almost not resistant to acetolysis. The wall is composed of a very thin exine and a thick intine. The exine is psilate, spinate, cerebelloid-areolate, striate, verrucate and foveolate. According to the presence or the absence of aperture and differential ornamentations, two types and six subtypes are recognized: I. The type Nonaperturate: (85 species and 3 varieties in 18 genera). Four subtypes can be recognized within the type based on the characteristics of the exine sculpture. These are: (1) The subtype Psilate, in which, the exine is nearly smooth (including: Hedychium, Curcuma, Kaempferia, Caulokaempferia coenobilis, Boesenbergia rotunda, Stahlianthus, Amomum compactum, Etingera, Hornstedtis, Rhynchanthus). (2) The subtype Spinate, which comprises two groups: (A) The group Short-spinate, pollen grains with smaller spines (Globba), (B) The group Long-spinate, pollen grains with longer spines (Alpinia, Amomum, Plagiostachys, Roscoea, Cautleya, Boesenbergia fallax, Caulokaempferia yunnanensis). (3) The subtype Cereblloid-areolate, pollen grains of which are spherical or subspherical, with cerebelloid sculpture (Zingiber Sect. Zingiber). (4) The subtype Striate, pollen grains of which are prolate or oliveshaped, and striate (Zingiber Setc. Cryptanthium). II. The type Aperturate, in which pollen grains are acetilysis-resistant and possess distinct apertures (mixed colpate-porate or forate), including two subtypes: (1)The subtype Mixed colpate and Porate. Pollen grains are both 3-colpate and 1-3-porate, and usually with one long spiral, two short (straight or slightly curved) colpi and 1-3-poris. The exine is verrucate or not, nearly sinuolate (Costus speciosus, C. tonkinensis, C. lacerus). (2) The subtype porate, whose grains are 6-8-porate and exine is foveolate (Costus megalobractea). The taxonomic significance of the pollen types in the family Zingiberaceae is also discussed.  相似文献   

15.
The pollen morphology of 11 species (including two subspecies and two varieties) belonging to two genera (Helianthemum and Fumana) of the family Cistaceae in Egypt was studied using light and scanning electron microscopy.Pollen grains of the studied taxa were found to be radially symmetrical and tricolporate.Pollen size,shape,apertures,and exine ornamentation characteristics were valuable parameters among the studied taxa.The largest pollen size was recorded in H.salicifolium and the smallest one observed in H.kahiricum subsp,schweinfurthii.Pollen shape in the Egyptian taxa varied from (sub-)prolate to prolate spheroidal,but F.arabica is different in having sub-oblate grains.The pollen data confirm that H.lippii and H.sessiliflorum are very closely related species.Pollen sculpture was useful in distinguishing between H.vesicarium var.vesicarium and H.vesicarium var.ciliatum.Three main pollen types of exine ornamentation were recognized:retipilate; reticulate to verrucate; and striate.Based on palynological data,a key for the studied taxa is suggested.  相似文献   

16.
Misodendraceae is a small family of mistletoes in the order Santalales. Its distribution is restricted to the southern South American temperate forests. The family comprises the sole genus Misodendrum with eight species of hemiparasitic shrubs, mainly parasitising the southern beech Nothofagus. This contribution presents palynological evidence from seven species, using light microscopy and scanning electron microscopy. Pollen grains are consistently small, periporate and echinate, although differences in the length of echini and number and size of pores were noted. Pollen features can be used to distinguish groups of species and, in some cases, individual species. Cluster analysis of pollen characters differentiates two main groups: one includes M. brachystachyum, M. oblongifolium and M. quadriflorum; and the other includes M. gayanum, M. linearifolium, M. punctulatum and M. angulatum. Palynological results are compared with previous systematic studies of the family. The South American fossil pollen record is summarised and characters of the fossil pollen are analysed using UPGMA to test the relationships between extant and fossil species. Miocene pollen resulted similar to species of subgenus Angelopogon while Eocene pollen is disimilar to extant species of Misodendraceae.  相似文献   

17.
The pollen grains of 33 species representing 11 genera of the family Berberidaceae, mostly from China, were examined with the light microscope and scanning electron microscope. Their characteritic details can be used for generic diagnosis. A pollen key to the genera based on these observations is presented. Based on the morphology, the pollen grains can be grouped into the following three types: 1. The tetrad pollen type found only in the genus Sinopodophyllum. 2. The spiraperturate pollen type found in the genera Berberis and Mahonia. 3. The tricolpate pollen type found in the genera Diphylleia, Jeffersonia, Nandina, Dysosma, Caulophyllum, Leontice and Epimedium. A diagnostic key to the pollen grains of genera in the Berberidaceae. 1. Pollen grains single 2. Pollen grains spiraperturate .................... Berberis L., Mahonia L. 2. Pollen grains tricolpate 3. Exine with spinose sculpture ........................ Diphylleia Michx. 3. Exine with non-spinose sculpture 4. Exine with striate or striate-reticulate sculpture ...... Jeffersonia Barton 4. Exine with reticulate sculpture 5. Exine around colpus with distinct thickening ........ Nandina Thunb. 5. Exine around colpus without thickening 6. Pollen grains larger (45—50)×(32.5—37.5)μ 7. Colpus with membrane ................ Dysosma R. E. Woodson 7. Colpus without membrane ................ Caulophyllum Michx. 6. Pollen grains smaller (25—550)×(20—527.5) μ 7. Pollen grains prolate-perprolate .................... Leontice L. 7. Pollen grains spheroidal-prolate...Epimedium L., Podophyllum L. 1. Pollen grains tetrad ............................ Sinopodophyllum Ying  相似文献   

18.
The Callitrichaceae are an aquatic family of dicots that include the single, geographically cosmopolitan genus Callitriche. Callitriche contains 40-50 terrestrial, amphibious, and obligately submersed species, and it is the only known genus in the plant kingdom with co-occurring aerial and hydrophilous pollination syndromes. Pollen morphology and ultrastructure were described for 13 Callitriche species using scanning electron and transmission electron microscopy. Representative taxa of each growth form were examined; these included three terrestrial species (C. deflexa, C. peploides, and C. nuttallii), nine amphibious species (C. brutia, C. cophocarpa, C. cophocarpa-stagnalis hybrid, C. cribrosa, C. hamulata, C. heterophylla var. heterophylla, C. lusitanica, C. marginata, and C. trochlearis), and one obligately submersed species (C. truncata). Of the amphibious taxa, C. heterophylla var. heterophylla and C. trochlearis had internal geitonogamy, a type of internal self-fertilization. Pollen from all taxa was spheroidal, small, intectate, and lacked well-defined apertures. Taxa primarily differed with respect to exine thickness, surface ornamentation, and the presence or absence of aperture-like regions. The pollen of terrestrial species, as well as that of C. marginata, had well-developed exines with thick sculptured and basal layers. In general, amphibious taxa produced pollen with distinct, but thinner, exines than that of terrestrial taxa. Pollen of the amphibious taxa with internal geitonogamy had a thicker basal layer than species without internal geitonogamy, whereas the overall exine was reduced in C. hamulata and absent in C. brutia and C. lusitanica. Pollen of the obligately submersed C. truncata also lacked an exine. These palynological data were correlated with growth habits and related pollination biologies, as well as with phylogenetic interpretations of Callitrichaceae. Exine reduction or loss has evolved at least twice in the family, and it is associated with aneuploid reduction in chromosome number.  相似文献   

19.
囊萼紫草属与滇紫草属花粉形态比较研究   总被引:3,自引:1,他引:2  
本文借助光学显微镜和扫描电镜研究了囊萼紫草属3种和滇紫草属12种植物的花粉形态。囊萼紫草属的花粉为哑铃形或茧形,中等大小,P/E比为1.6一1.67,三孔沟,内孔横长;具小刺状纹饰。滇紫草属的花粉为近长球形或近卵球形,P/E为l—1.23;三孔沟或三合沟孔,内孔一般纵长,具皱波状纹饰,在皱波上具密集的小瘤或微颗粒。从花粉形态的角度,本文支持把囊萼紫草属从滇紫草属(广义)中分离出来的观点。值得注意的是,在滇紫草属的花粉中首次观察到了一种比较少见且特化的花粉即单极三合沟孔的花粉。  相似文献   

20.
The plants of Kadsura longipedunculata (Schisandraceae) are monoecious and possess either red or yellow male flowers (the androecium), with yellow tepals, and yellow female flowers. All flower types simultaneously produce heat and floral odours (dominated by methyl butyrate) throughout a 4–5-h nocturnal period. The flowers are pollinated only by female, pollen-eating Megommata sp. (Cecidomyiidae). Pollen is the only reward, and female flowers use the same attractants as male flowers but offer no food (pollination by deceit). Open pollinated flowers in nature varied in fruit set from 8 to 92%. Megommata (subfamily Cecidomyiinae, supertribe Cecidomyiidi), consists of six described species, which feed on Coccoidea (scale insects) and are distributed worldwide.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 523–536.  相似文献   

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