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1.
卫矛属冬青卫矛组种皮和假种皮微形态研究   总被引:1,自引:0,他引:1  
利用扫描电子显微镜对冬青卫矛组(Sect.Ilicifolia Nakai)13种以及卫矛属其他组6种植物的种皮和假种皮微形态特征进行了研究.结果表明,冬青卫矛组植物种皮和假种皮的纹饰主要为网纹型,大致可划分为4个类型:(1)种皮纹饰为复网纹型,网眼隆起;(2)种皮纹饰为复网纹型,网眼中部下陷;(3)种皮纹饰为网纹型,假种皮嚼烂状;(4)种皮纹饰为网纹型,假种皮网纹状.种皮和假种皮微形态特征在对近缘种的分类上提供了一定的参考依据.  相似文献   

2.
对金丝桃属5组9种植物的种子进行了宏观及微观形态学研究,以探讨岐山金丝桃的系统位置。结果显示,种子形态特征在本实验观察的5个组之间有明显差异。其中金丝桃组种子外形较为细长,种皮纹饰为狭长而规则的矩形网纹;黄海棠组种子稍粗,种皮纹饰为长宽近等的多边形(稀矩形)网纹;元宝草组的元宝草、贯叶连翘组的贯叶连翘以及挺茎遍地金组的云南小连翘种子均较小,元宝草种皮纹饰为负网纹,贯叶连翘种皮纹饰为相邻网纹间有间隙的近圆形网纹,云南小连翘种皮纹饰为复网纹。研究显示,岐山金丝桃的种子形态与黄海棠组最为接近,支持岐山金丝桃归于黄海棠组。  相似文献   

3.
利用光镜(LM)和扫描电镜(SEM)对十大功劳属24种植物的种子形态进行观察。结果发现十大功劳属植物种子颜色为黑色,长3.4~6.7mm,宽1.7~3.5mm,属大型种子,形状多样;外种皮纹饰为网纹状,网眼形状、大小及网脊粗细、凸凹在不同类群间不完全相同,种内变异稳定,据此可将十大功劳属植物种皮纹饰划分为9种类型。研究结果表明:种子形态在十大功劳属内具有重要的系统学意义,但不支持Ahrendt将十大功劳属下分为2个groups,4个sections,14个subsections的观点。  相似文献   

4.
利用解剖镜和扫描电镜对小檗科5属(小檗属、十大功劳属、鬼臼属、山荷叶属和红毛七属)40种2变种植物种子形态进行观察。研究结果表明:小檗科植物种子颜色多为黄褐色、红棕色至黑色,形状多样;种皮纹饰可分为网纹型、网纹—梯纹型、梯纹型和嚼烂状4种类型,其中网纹型又可划分为7个亚型。种子球形、种脐位于种子侧面近中部可作为红毛七区别于其他属种子的重要形态特征。根据种皮微形态特征,探讨了种子形态在小檗科内的系统学意义,并推测了种皮纹饰的可能演化路线。种子形态支持小檗属和十大功劳属的近缘关系,认为鬼臼属(八角莲属)较山荷叶属分化更早,但不支持Ahrendt对小檗属下组和亚组的划分。  相似文献   

5.
中国车前属种子形态及其分类学意义   总被引:7,自引:0,他引:7  
本文研究了中国车前科Plantaginaceae车前属plantago2亚属8组17种及1变种植物的种子, 在扫描电子显微镜下的形态及亚显微结构(种皮纹饰).结果表明种子形态有四个类型:1,多角形类型;2.舟形类型;3.卵形类型;4.矩圆形类型。各个种的种子形态和种皮纹饰有着相当明显的区别。新种plantago densiflorus的建立应用了种子形态和种皮纹饰这一特征。车前种子形态分类与pilger用植物其他形态特征建立的车前属分类系统是一致的,因此,笔者支持Pilger的车前属分类系统。  相似文献   

6.
利用体视显微镜和扫描电子显微镜观察了荒漠植物多裂骆驼蓬粘液质种皮吸水前后的形态变化,通过种子吸水 脱水、粘土、漂浮和萌发实验研究了种皮纹饰和粘液特征在种子扩散和萌发中的适应意义,以期为研究该物种在荒漠环境中的适应策略提供理论依据。结果表明:(1)多裂骆驼蓬种皮纹饰由表皮细胞外切向壁的附属物向外突起形成,呈多面体网纹状;种皮纹饰上覆盖1层粘液薄膜,将多面体网眼围成封闭的腔,种子吸水后粘液薄膜变成凝胶状,腔内有气泡产生;粘液薄膜经过反复吸水 脱水后逐渐溶解消失。(2)种皮网眼状腔室结构和粘液薄膜可使种皮纹饰内储存空气,以增强种子的漂浮能力,有助于种子扩散;种皮纹饰和粘液还增强了种子的粘土能力,使种子锚定在土壤表面,避免种子裸露和活力丧失;此外,种皮纹饰及粘液的快速吸水和保水能力能防止种子失水,有效维持该物种在荒漠环境中的土壤种子库。(3)种皮纹饰和粘液虽可抑制种子萌发,但能促进幼根的伸长生长,对增强幼苗的建植能力有一定积极作用。  相似文献   

7.
唐宏亮  贺学礼 《植物学报》2007,24(5):614-619
利用扫描电镜观察了国产岩黄耆属(Hedysarum L.)18个种(含3个居群)的种皮纹饰。结果表明: 岩黄耆属种皮纹饰性状在种的划分上具有重要的分类学意义。依据种皮纹饰特性, 大致分为光滑型和粗糙型2大类型以及断棱状、嚼烂状、龟纹状、网纹状与细网状5个亚型。依据其划分的类型及亚型, 种皮纹饰呈现出从断棱状、细网状到光滑状的演化趋势, 从而阐明了种皮纹饰在岩黄耆属系统演化上的重要意义。  相似文献   

8.
中国岩黄耆属(豆科)种皮纹饰及其系统学意义   总被引:1,自引:1,他引:0  
利用扫描电镜观察了国产岩黄耆属(Hedysarum L.)18个种(含3个居群)的种皮纹饰。结果表明:岩黄耆属种皮纹饰性状在种的划分上具有重要的分类学意义。依据种皮纹饰特性,大致分为光滑型和粗糙型2大类型以及断棱状、嚼烂状、龟纹状、网纹状与细网状5个亚型。依据其划分的类型及亚型,种皮纹饰呈现出从断棱状、细网状到光滑状的演化趋势,从而阐明了种皮纹饰在岩黄耆属系统演化上的重要意义。  相似文献   

9.
鸢尾属部分种种子微形态特征与系统演化关系   总被引:3,自引:0,他引:3  
王玲  卓丽环 《植物研究》2006,26(3):286-290
用HITACHI S-520型扫描电子显微镜对鸢尾属植物10个种及1变种、1外类群的种子微形态进行观察、比较分析,探讨了鸢尾属植物部分种种子微形态特征分类学意义及系统演化关系。结果表明:鸢尾属植物种子表面微形态特征具有种的稳定性,与分布区无关;同一种的种子凹、凸面微形态差异很大,同一类群比较时应选择相同部位观察。所研究的鸢尾种都为网状(网纹或负网纹)文饰,种间差异明显,微形态特征可用于鸢尾属间、属下系的等级划分,但不适于种下等级鉴别。研究给出了鸢尾属植物种子表面纹饰的系统进化关系,证明了种子表面微形态对鸢尾属植物分类及系统演化关系具有重要意义。  相似文献   

10.
利用扫描电镜和解剖镜对西藏色季拉山区分布的龙胆科6属20种植物种子微形态进行观察研究。结果显示:这20种植物的种子颜色有黑色、黄色、黑褐色、黄褐色、灰褐色和红棕色6种;种子形状分为长卵球形、卵球形、椭圆球形、矩圆形和近球形;表皮纹饰可分为4种类型,即网纹型、条纹型、疣状型和嚼烂型,其中网纹型又细分为6个亚型。根据种子微形态特征,笔者对龙胆科相关属的进化趋势、分类学意义和分类鉴定等进行了讨论,认为獐牙菜属(Swertia L.)和龙胆属(Gentiana(Tourn.)L.)进化程度较高;从种子微形态特征上看肋柱花属(Lomatogonium A.Br.)、花锚属(Halenia Borkh.)和假龙胆属(Gentianella Moench.)间有较近的亲缘关系;龙胆科各属种子表皮纹饰特征与分类系统基本吻合。本研究表明种子微形态在植物分类研究中具有十分重要的意义,可作为植物系统划分、鉴定和进化研究的参考性状。  相似文献   

11.
双蝴蝶属和蔓龙胆属(龙胆科)种子表面特征的研究   总被引:4,自引:1,他引:3  
在扫描电镜下观察了龙胆科双蝴蝶属8个种和蔓龙胆属6个种的种子表面纹饰,观察结果表明,2属的种子表面特征均为网状纹饰类型。其中Tripterospermun cordatum,T.volubile,T.chinense,T.discoideum,T.japonicum,T.filicaule,Crawfurdia delavayi和C.pri-cei的种子表面为细网状;T.hirticalyx,T.pingbianense,C.puberula,C.tibetica,C.campanu-lacea和C.crawfordioides的种子表面为粗网状,在龙胆属Gentiana的不同组中均存在网状纹饰,因此,从种子表面特征可看出,龙胆属,双蝴蝶属和蔓龙胆属3属间具较近的亲缘关系。同时,在双蝴蝶属中,种之间在种子表面特征上有分化。在表面纹饰的具体特征上存在较大差别,而在蔓龙胆属中种间差别很小,仅在一些种子表面有无附属物上存在差异。  相似文献   

12.
Studied in this work was seed morphology of the genus Plantago (2 subgenera, 8 sections, 17 species and 1 variety )in China. The sculpture was observed under scanning election microscope. Four forms of seed morphology are recognized as follows: (1)Multi-angular type: seeds are variously angulate, yellow-brown or black, 6-30 in a fruit; seed-coat sculpture ranges from reticulate to papillate. It occurs in Subgen. Plantago Sect. Polyneuron: P. scheideri, P. denstflorus, P. major, P. hostifolia, P. asiatica, P. erosa and P. centralis. (2) Navicular type: seeds are navicular, yellow, brown to black, 2 in a fruit; seed-coat sculpture is reticulate. It was found in Subgen. Plantago Sect. Novorbis: P. virginica; Sect. Arnoglossum: P. lanceolata; Sect. Leucopsyllium: P. minuta, P. lessingii and P. aristata and Subgen. Psyllium Sect. Psyllium: P. indica. (3)Ovoid type: seeds are long-ovoid, yellow-brown, black and lustrous. Seed-coat sculpture scali-ratiform. P. maxima in Subgen. Plantago Sect. Lamprosantha belongs to this type. (4)Recti-circular type: seeds are recti-circular, yellow-brown, black, 1-2 or 4-5 in a fruit; seed-coat sculpture is reticulate and papillate. It was found in P. maritima var. salsa of Subgen. Plantago Sect. Coronopus and P. depressa, P. camtschatica and P. arachnoidea of Sect. Mesembrynia. The seed morphology and seed-coat sculture exhibit specific characters, by which some of confused species can be clarified and a new species, P. densiflorus J. Z. Liu. is established. The present author’s seed morphology classification is in accordance with Pilger’s systemof the genus, which was established using other features.  相似文献   

13.
中国滨藜属种子形态及其分类学意义   总被引:7,自引:0,他引:7  
本文对中国滨藜属(Atriplex L.)13种植物的种子形态进行了观察并探讨其在分类学中的意义. 在种子外部形态观察基础上明确了胚根位置类型的划分标准, 认为滨藜属胚根位置仅有胚根上位和胚根侧位两种类型;利用扫描电镜首次观察报道了该属种皮微形态特征。研究结果表明, 种子形态及种皮微形态特征对属内类群划分具有较大的分类学意义。  相似文献   

14.
Seed morphology of 29 taxa including 9 subgenera belonging to the genus Veronica was compared using scanning electron microscopy to assess their diagnostic value for systematic studies. Subgenus Beccabunga is the largest in this study represented by nine taxa. Seed surface often varies from ridged reticulate or verrucose/granulate reticulate to rugose-reticulate. Seed color and size have limited taxonomic significance as their variation is uninformative. Thereagainst, seed shape and seed coat ornamentation present informative characters that can be used efficiently in distinguishing the studied taxa. Our seed features support the DNA sequence data in showing close relationships between V. biloba and V. campylopoda, and between V. fruticans and V. fruticulosa. The present study indicates thatV. anagallis-aquatica, V. anagalloides, V. comosa, and V. catenata have more or less the same seed features; consequently, these four former species are most likely representing a single species as reported by earlier studies. Furthermore, V. polita and V. persica are very similar in terms of seed characteristics. Our results justify placement of V. peregina within subgenus Beccabunga and support the monophyly of the subgenus Veronica.  相似文献   

15.
Tülay Aytaş Akcin 《Biologia》2009,64(6):1089-1094
The seed coat morphology of 10 Campanula species from Turkey, 3 of which are endemic, was studied using scanning electron microscopy. Characteristics of the seeds and their surface morphology were described and compared. Two different types were described based on seed surface features. The Type 1 seed surface was characterized by a reticulate pattern; only C. Olympica belonged to this type. The Type 2 seed surface had a striate testa and was the most common type. It included C. Lyrata subsp. lyrata, C. rapunculoides L. subsp. rapunculoides, C. glomerata L. subsp. hispida, C. involucrata, C. saxonorum, C. persicifolia, C. latiloba subsp. latiloba, C. lactiflora and C. Rapunculus L. var. lambertiana. However, some differences among these species were determined on the basis of their seed surface features at the microstructural level. These features were evaluated as possibly consistent parameters in the delimination of the Campanula taxa studied.  相似文献   

16.
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   

17.
利用扫描电镜对35种1变种柃属(Eurya)植物种子的微形态特征进行了研究,并采用相对大小(长×宽)RS值和种皮表面纹饰作为种子形态比较的特征参数。结果显示,柃属种子根据相对大小RS值可划分为小型(RS<1.0),中型(1.03.0)三个等级,最小的种子相对大小不足0.5,最大的种子相对大小超过10;种皮表面纹饰分为负网纹和网纹两种类型,网纹类型在网眼的方向性、网眼形状、网眼深度、网脊特点等方面呈现出种间多样性,可用于类群的比较和鉴别。文中同时还探讨了种子大小及种皮微形态在属内的系统发育关系,推测了种皮表面纹饰的演化路线,研究结果表明种子的微形态特征对本属植物系统分类及进化研究具有重要意义,可为属内一些关键种系统位置的分析提供重要佐证。  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 (Parnassia faberi Oliv.) colpi,implying that Southwest China is the center of diversification of the genus.  相似文献   

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