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1.
南天竹属的花部器官发生及其系统学意义   总被引:2,自引:1,他引:1  
报道了南天竹(NandinadomesticaThunb.)(小檗科)的花部器官发生。发现该属植物萼片、花瓣和雄蕊的发生式样为三数轮生;雄蕊与花瓣是经它们所具有的共同原基进行侧向分裂而形成的;花瓣发育早期存在迟滞发育的阶段;心皮发生属于瓶状发生类型。讨论了花器官的三基数性质,小檗科花瓣的来源,雄蕊对瓣着生及单心皮雌蕊的形成等问题。对本属的花部个体发育性状同小檗科中已有报道的红毛七属(Caulophylum)、足叶草属(Podophylum)进行了比较,萼片多数轮列与心皮发生的多态现象是南天竹属的独特性状。  相似文献   

2.
A hybridization study was made utilizing 37 species of 10 sections in 41 intra- and intersectional combinations. A total of 721 pollinations was made with 138 fruits harvested; 89 produced viable crosses. Five intrasectional and 20 intersectional combinations resulted in successful hybrids. Among the intrasectional crosses, Phalaenanthe × Phalaenanthe exhibited the highest percentage of fruits and successful crosses while Callista × Callista produced no successful crosses. Eugenanthe × Eugenanthe exhibited low crossability. Among the intersectional crosses, Ceratobium × Phalaenanthe gave the highest percentage of successful crosses, indicating a close relationship between the two groups. Also, there appears to be a fairly close relationship between Latourea and Ceratobium based on crossability. Although the sectional classification of the genus by Schlechter on the basis of vegetative and floral morphology appears to be valid, crossability studies suggest that the Ceratobium and Phalaenanthe sections might be integrated and the Eugenanthe section separated into sections or subsections.  相似文献   

3.
葡萄属营养器官的比较解剖学及其系统学意义   总被引:7,自引:0,他引:7  
本文对国产葡萄属24个种、6个变种和4个美洲种进行了比较解剖学研究。比较观察了茎、节、 叶柄、叶片的维管系统、厚角组织、厚壁组织、毛状体、后含物、叶表皮角质等解剖学特征。并讨论了它们在系统学上的意义。  相似文献   

4.
我国西南地区独活属花粉形态及其系统学意义   总被引:8,自引:1,他引:7  
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5.
中国兜被兰属植物的花粉形态及其分类意义   总被引:2,自引:0,他引:2  
兜被兰属Neottianthe全世界共约12种,中国均有分布,其中9种为我国所特有。本属花粉形态 和组成都很特殊,它是由许多单粒花粉粘结在一起形成复合花粉——花粉小块,其形状一般为狭长的三 棱锥体形。外壁表面具5种纹饰类型:(A)近光滑,或具十分微弱的小凹陷;(B)外壁具穿孔状纹饰; (c)外壁具沟渠状纹饰;(D)外壁具拟网状纹饰;(E)具典型的网状纹饰。奉属有些种类,例如:N.cal- cicola,N.monophylla,N.pseudo-diphylax和N.cucullata等4种在分类上还存在许多问题,有些分类 学家把N.calcicola,N.monophylla,N.pseudo-diphylax 3种均归并于N.cucullata。孢粉学资料表 明上述4个种花粉特征完全不同,因此,上述4种仍应各自独立为种。最后,强调指出N.camptoceras的花粉形状和外壁纹饰等特征在本属为特殊类型。  相似文献   

6.
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   

7.
Two closely related North American orchid species, Isotria verticillata and I. medeoloides, were studied with respect to breeding system biology and pollination dynamics. Marked differences in reproductive biology were revealed. The more common I. verticillata is xenogamous, being pollinated by solitary bees in the Andrenidae, Anthophoridae, and Halictidae. The inflorescence is fragrant, multicolored, and has pollination guides, thus possessing an obvious attractant system, even though it lacks nectaries. In contrast, I. medeoloides is self-pollinating, has light green flowers, and lacks pollination guides, nectaries, and odor. These two species also differ radically in population structure and reproductive efficiency.  相似文献   

8.
角叶铁破锣的核型及其系统学意义   总被引:6,自引:4,他引:2  
本文首次报道了角叶铁破锣的核形态。其静止核和有丝分裂前期染色体分别属于复杂中央染色微粒型和中间型;中期染色体数目为2n=16;核型公式为2n=10m+4st十2t(2sat)。根据上述结果并结合有关资料,本文讨论了铁破锣和角叶铁破锣之间的核型差异以及铁破锣属的系统位置,指出铁破锣属可能与升麻属等类群关系较近而与金莲花属等类群关系较远,因此将该属置于升麻族中比置于金莲花族中合理。  相似文献   

9.
The pollen morphology of 117 species and varieties of Mimulus was examined by light and scanning electron microscopy. Five major and 8 more tentative, minor types were found based on the differential correlation of aperture type, exine morphology, pollen grain diameter and other characters: type 1—synaperturate, usually ±spiraperturate, exine perforate to microreticulate with supratectal processes; type II—trocolporate, exine microreticulate (IIa and IIb, supratectal processes absent; IIa, mean polar axis 16–19 μm; IIb, mean polar axis 25–35 μrn; IIc, supratectal processes present); type III—tricolpate, colpus membrane ±psilate. exine with supratectal processes (IIIa, exine microreticulate and 1.4–2.0 μm thick, polar axis ≥ 30 μm; 111b, exine densely perforate and 2.2–2.8 μm thick, polar axis ≤ 23 μm); type IV—tricolpate, colpus covered with spinulose granules (operculate), exine microreticulate with supratectal processes; type V—5–7 stephanocolpate (Va and Vb, colpus margins ±straight and nongranular; Va, exine microreticulate with supratectal spinules; Vb, exine perforate with supratectal spinules or spinulose verrucae; Vc, colpus margins ragged and granular, exine microreticulate with supratectal processes). The pollen data correlate well with geographical and macromorphological data and, where the latter are ambiguous, often provide important clues toward the resolution of conflicting interpretations of infrageneric classification and generic delimitation.  相似文献   

10.
国产大苞姜属和苞叶姜属种子解剖学特征及其系统学意义   总被引:9,自引:0,他引:9  
廖景平  吴七根   《广西植物》1996,16(3):209-215
黄花大苞姜和苞叶姜分别是大苞姜属和苞叶姜属在中国分布的唯一代表。黄花大苞姜种子椭圆形,具表皮毛,无假种皮;苞叶姜种子卵圆形,无毛,假种皮盘状。二者的种子均包含种皮、外胚乳、内胚乳与胚四部分。种皮均可分为外种皮、中种皮与内种皮,且中种皮包括下皮层、半透明细胞层与色素层。合点区内种皮均出现缺口,缺口间充满合点区色素细胞群。苞叶姜种皮有7~9层细胞,其中色素层3~5层细胞,而黄花大苞姜仅有5层,各部分均只有1层细胞,是迄今研究过的姜科植物中种皮细胞层数最少的。在珠孔区,苞叶姜具明显的柄状结构,并有珠孔领和孔盖的分化;而黄花大苞姜柄状结构短,且不明显,无珠孔领。因此,种子解剖学支持将苞叶姜从大苞姜属分出并提升为属。同时,根据姜目较原始类群的种子没有珠孔领分化,推测黄花大苞姜可能保留了姜科某些较原始的特征.  相似文献   

11.
七筋姑属叶表皮形态特征及其系统学意义   总被引:4,自引:2,他引:4  
利用扫描是镜和光地七筋姑属北美全部4种和东亚1种11个居群的叶表皮形态进行了观察。其总体特征如下;上表皮细胞5-7边形、近等径或狭长,下表皮细胞长条形;垂周壁向外隆起,平直,有明显加厚或加厚不明显,平周壁内陷,平滑具浅坑,有时具细条纹状纹饰或细小突起。气孔器散生于下表皮,均为无规则型,长度约为表皮细胞的1/4-1/3,隆起于表皮细胞或有时稍下陷。北美4种中,C.uniflora下表皮生有长的扁平状  相似文献   

12.
似鳡属(Luciocyprinus Vaillant)是鲤科鱼类中属于鲃系(陈湘粦等,1984)的一个属,下咽齿3行,臀鳍无硬刺,具分枝鳍条5根。过去只记载一个种,外形很像鳡鱼,是由于摄食习性相同而导致的趋同现象(林人端,1981),故称似鳡,在广西俗称墨线鳡,云南俗称杆条鱼。分布于西江水系,包括云南中南部的湖泊,与鳡鱼分布于同一水系,但各占一定的水域,互不重叠。 关于似鳡的拉丁名称,惯用Fustis vivus Lin,是林书颜1932年定的新属新种,  相似文献   

13.
Endothecial cell thickenings were examined in anther macerations of representative species from 210 genera of the Orchidaceae. Nearly all species examined possessed the characteristic thickened walls which, in several tested species, gave a positive reaction to phloroglucinol, indicating the presence of lignin. Four basic thickening types were identified; distribution of the types was found to be largely in agreement with previously recognized suprageneric groups. Type I thickenings are tightly packed channels of loops or helices and were found in the “neottioid” genera, the Apostasioideae, and putatively basal genera in the remaining subfamilies. Because of its occurrence in the Apostasioideae, which is believed to be the most basal subfamily, Type I is hypothesized to be the plesiomorphic thickening type for the remainder of the Orchidaceae. Type II thickenings appear as scattered loops and may be a synapomorphy for the Orchidoideae, as they were found in all genera sampled from the subfamily except Disperis. Type III thickenings are circular in appearance and were found in the Cypripedioideae and in some members of the Spiranthoideae and Epidendroideae. Type IV thickenings show little regular arrangement, appearing to be scattered bars, and were observed primarily in the Epidendroideae and also in some Spiranthoideae. Three subtypes were recognized in Type III and Type IV. Some genera, such as Triphora, Goodyera, and Elythranthera, had thickenings that appeared intermediate between the recognized types. In general, terrestrial genera were found to have regularly arranged, well-developed thickenings, while many epiphytic groups showed congested, irregular, thinner thickenings.  相似文献   

14.
15.
本文对中国特有单种属-马蹄香属进行了细胞学研究,首次报道马蹄香花粉母细胞的单倍体染色体数目n=13,体细胞的染色体数目为2n=26,x=13,核型公式为2n=12m+4sm+10st,染色体的范围2.51-6.80μm,为中型染色体,2B核型。这与前人报道的2n=24,2A核型和2n=4x=52,染色体长度不超过1μm、是多倍体等结果均不相同。马蹄香是马兜铃科中最原始的属,核型资料表达它与细辛属部  相似文献   

16.
17.
Tilosomes, also called “fibrous bodies” or “rod bodies” in older literature, are lignified excrescences from the walls of cells of the innermost velamen cell layer adjacent to thin-walled passage cells of the exodermis in roots of many epiphytic orchids. Seven broad morphological types are recognized: spongy, lamellate, discoid, webbed, meshed, baculate, and plaited. Some types characterize specific genera or subtribes of Orchidaceae. Of the 350 species in 175 genera included in a survey of the family, tilosomes occur in 95 species and 39 genera and are concentrated in tribe Polystachyeae and subtribes Sobraliinae, Coelogyninae, Laeliinae, Pleurothallidinae, Bulbophyllinae, Lycastinae, and Maxillariinae. With the exception of the pantropical genera Bulbophyllum and Polystachya and the Paleotropical subtribe Coelogyninae, tilosomes are almost exclusively Neotropical phenomena.  相似文献   

18.
毛冠菊属的花粉形态和结构及其系统学意义   总被引:1,自引:0,他引:1  
对国产菊科特有属的花粉形态和结构进行了光学显微镜、扫描电镜和透射电镜的观察和研究。该属的花粉可以分为圆球形、扁球形和长球形三种类型。种之间的花粉差异主要表现在大小、形状和外壁纺饰的细微变化等方面。与紫菀族、竿里光旋和旋覆共族三个族的代表种的花粉特征进行对比分析,并结合其它生物演化证据,可得取以下结论:(1)支持and-Mazzetti的分类意见,毽炙属应归于紫族中;(2)毛冠菊属的花粉可划分为圆球  相似文献   

19.
鹅掌楸属花粉的超微结构研究及系统学意义   总被引:23,自引:4,他引:19  
  相似文献   

20.
牛永春  魏江春 《菌物学报》1993,12(Z1):25-29
本文从分子系统学角度为石耳科两个疑难种的分类处理提供了佐证。真菌DNA是从淡腹疱脐衣及露西疱脐衣不含藻细胞的亚茶渍型子囊盘中提取后,用聚合酶链式反应(PCR)技术对于核中核糖体脱氧核酸((rDNA)的转录间区2 (ITS2)片段进行了扩增,并进行了核苷酸序列测定。在分子水平与形态特征以及化学与分布学相结合中进行了比较系统学分析。  相似文献   

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