共查询到19条相似文献,搜索用时 125 毫秒
1.
2.
3.
4.
利用叶绿体DNA的trnL内含子和trnL-F基因间隔区序列测定,对中国独行菜族部分属及相关属植物进行了分子系统学研究,结果表明:独行菜族是多系类群,在分子树中,所研究的中国独行菜族部分属植物被分别聚在了3个不同的并列系中,其中,荠属(Capsella)和亚麻荠属(Camelina)与南芥族的3个属聚在系Ⅰ,认为应将二者分别从独行菜族和大蒜芥族中移出,划入南芥族中;菥蓂属(Thlaspi)和菘蓝属(Isatis)与大蒜芥族的3个属聚成系Ⅱ,支持将二者移出独行菜族,划入大蒜芥族的观点;独行菜属(Lepidium)、臭荠属(Coronopus)和群心菜属(Cardaria)三者关系密切,组成系Ⅲ,其中臭荠嵌入独行菜属中,支持将臭荠属合并到独行菜属的处理意见. 相似文献
5.
6.
两种独行菜种子萌发生理特性研究 总被引:2,自引:0,他引:2
以两种在新疆具有代表性的十字花科独行菜属早春短命植物抱茎独行菜(Lepidium perfoliatum Linnaeus)和独行菜(Lepi-dium apetalum Willd)为材料,研究(光照、温度、外源激素ABA处理)对其种子萌发的影响。结果:两种独行菜种子萌发对光照不敏感;抱茎独行菜种子萌发的温度范围广,在0℃~25℃之间都可萌发,而独行菜种子则在低温下(0℃、4℃)不萌发,其萌发温度范围为10℃~25℃。两种独行菜种子对低温胁迫表现出不同的耐受性;0℃、4℃下,在培养基中加入不同浓度的ABA,对抱茎独行菜种子萌发有抑制作用。 相似文献
7.
利用光学显微镜对中国十字花科独行菜族部分广布属及相关属植物进行了叶表皮微形态学观察研究,结果表明:所研究的中国独行菜族植物叶表皮微形态具有多样性,可以划分为两种类型:第一类,叶上下表皮同形或近同形,叶表面被单毛或光滑无毛,包括独行菜属、群心菜属、菘蓝属和菥蓂属;第二类,叶上下表皮不同形,叶表面被分支毛和单毛,包括荠属和亚麻荠属;叶表皮微形态结果支持荠属应从独行菜族中移出,独行菜族是一多系类群,同时认为荠属与亚麻荠属植物具有较近的亲缘关系。 相似文献
8.
短命植物独行菜种子萌发过程对低温的耐受特性 总被引:2,自引:0,他引:2
以独行菜(Lepidium apetalum)为材料,研究了其种子在萌发过程中耐受低温的特性,并对耐受低温的机制作了初步的探讨。结果表明:1.萌发至I、II、III期的独行菜种子经过冷诱导处理后,对零下低温-5℃、-10℃胁迫具有较强的耐受性,这种耐受性随萌发发展相对有所降低。2.独行菜种子萌发过程中胚根生长速度明显受到低温抑制,但也仍然能够生长。3.适当时间的低温层积能使独行菜萌发势显著提高,对终萌发率影响不大;过长时间的低温层积会使独行菜种子萌发势和最终萌发率降低。4.独行菜种子在4℃条件下不能萌发,但4℃层积2d的种子经25℃处理6h以上后,可耐受4℃低温而萌发,且萌发率随25℃处理时间增加而升高。如果25℃处理时间少于5h则不能在4℃低温下萌发。经4℃层积10d、再经25℃萌发处理1h的独行菜种子就能在4℃低温下萌发。综合分析认为独行菜种子不能耐受4℃低温萌发,原因可能是在露白前存在一个关键的生理阶段,在4℃胁迫逆境中不能越过这个阶段,该阶段之前与之后的萌发过程都能耐受4℃低温,因此对低温胁迫有良好的耐受性。这为探索早春短命植物耐受低温萌发的机制提供了新的思路。 相似文献
9.
独行菜属植物叶片脉序的比较观察 总被引:7,自引:0,他引:7
对独行菜属(Lepidium)8种,1变种进行了叶片脉的比较观察,结果表明:它们的一级脉中等粗细,基部1~2对侧生,一级脉与二级脉连志成拟环结两行羽状脉;三级脉贯穿型或结网型,叶缘末级脉为不完全型,网眼大小,形状不规则,发育均为不完善型,可为探讨十字花科的系统演化提供一些形态学依据。 相似文献
10.
新疆短命植物抱茎独行菜种子粘液质特性的研究 总被引:1,自引:0,他引:1
以新疆荒漠植物抱茎独行菜为材料,运用光镜与扫描电镜观察以及紫外吸收光谱法、化学反应及种子萌发实验等方法,对粘液质的形态和结构,物理化学特性,粘液质对种子萌发及萌发后的影响进行了研究.结果显示:(1)完整干种子表面覆盖着一层膜状物质(完全脱水的粘液质),并呈同一走向的山脊状突出的网状结构,遇水后粘液物质呈射线状向外发射出来,化学反应实验结果表明,粘液质的组成可能是某种多糖,如β-葡聚糖.(2)粘液质约占干种子重量的1/4,有很强的吸水能力,完全浸润10 min后,种子重量增加约30~40倍,种子长度、宽度、厚度的增加分别多于1倍、2倍、4倍;完全润湿的种子能够粘附相当于其干种子重量68倍的沙粒.(3)种皮粘液质对于不同土壤基质中的种子萌发有重要作用,但是对萌发后幼苗的生长没有作用. 相似文献
11.
中国蓼族植物系统分类研究综述 总被引:10,自引:0,他引:10
关于蓼族属级及属下分类问题,分类学家持有不同的意见。介绍了自蓼属建立以来,蓼族植物分类的研究现状,认为蓼族在系统分类上尚需进一步的研究。 相似文献
12.
八角属(八角科)植物的种子形态 总被引:4,自引:1,他引:3
在光学显微镜和扫描电镜下对八角属(Illicium Linn.) 15种植物(33个样品)的种子形态进行了观察和描述。八角属植物种子形态多为倒卵球形,少椭球形或卵球形,侧向压扁;外种皮石质,中种皮革质,内种皮膜质;外种皮淡黄色、卵黄色至橙褐色,具蜡被,极光滑,有光泽,无纹饰,腹部有一凸起的纵棱(种脊),由种脐延伸至顶端;种脐位于基端偏向腹部一侧或位于基端,卵形或椭圆形,下凹;胚微小,胚乳丰富,含油。该属植物种子的形态特征非常相似,表明该属是一个自然的单系类群。 相似文献
13.
牛奶菜族7属11种植物的花粉器形态 总被引:1,自引:0,他引:1
在光学显微镜和扫描电子显微镜下观察了萝藦科(Asclepiadaceae R.Br.)牛奶菜族(MarsdenieaeBenth.)7属11种植物花粉器的形态特征。该族植物花粉块直立或平展,通常呈椭圆形、长圆形、肾形或球形;花粉块膜表面平滑、波浪状、脊状或粒状;娃儿藤属(TylophoraR.Br.)的花粉块膜具独特的表面纹饰,与其它属植物差异较大;匙羹藤属和娃儿藤属的花粉块柄不发达,眼树莲属(Dischidia)和纤冠藤属(Gongronema)的花粉块柄发达。 相似文献
14.
Pollen grains of 16 species of Microula Benth. and six species of three
related genera were examined under LM and SEM, and four of them also under TEM. Pollen grains of Microula and three related genera are dumb-bell-shaped, 3-colporate apertures alternate with three pseudocolpi. Pollen grains are very small,ranging from 12.18 x 7.13 μm to 6.36 x 3.66μm. In general, colpi with os are
wider and shorter, rhomboid, but sometimes they are equal to pseudocolpi in length. Colpus margins are regularly or irregularly tooth-like. The surface of colpi is psilate or processed. Ora are circular or lalongated in outline, protruded or not; surface of os membrane is smooth or scabrid. The exine is usually indistinctly layered under LM. The exine surface is psilate, and more or less perforate. TEM examination shows that the pollen wall is differentiated into exine and intine: the exine includes ectexine and endexine, while the ectexine consists of
tectum, columellae and foot-layer. However, there are differences in constriction of equatorial area, apertural characters, ornamentation and exinous ultrastructure between these genera. Pollen morphology indicates that the genus Microula Benth. is primitive, directly related to the genus Actinocarya Benth .; the genus Asperugo L. Is more advanced. The genus Eritrichium Schrad. which has two ora or one os and is anisopolar, represents the most advanced group among them. Noteworthily, the diorate phenomenon is found for the first time not onlyin the genus but in the family Boraginaceae. 相似文献
15.
对螺序草属(Spiradiclis B1、)16种2变型共18个样品的种子形态特征的初步研究表明,本属植物种子为小型(0.2—0、3mm)或中型(0.3—2mm),整体形状不太规则,表面纹饰为蜂窝状,种脐稍突出。种子的外壁由内外2层种皮组成。依据表面突起分布方式,螺序草属的种子大致分为2种类型:(1)平周壁微下陷,疣突均匀分布于其上,如大叶螺序草、螺序草、尖叶螺序草、柳叶螺序草、峨嵋螺序草和龙州螺序草;(2)平周壁下陷成穴状,突起分布在穴边缘,如红花螺序草、心叶螺序草、两广螺序草、广东螺序草、海南螺序草、宽昭螺序草、疏花螺序草、多枝螺序草、罗氏螺序草、小叶螺序草、石生螺序草和紫花螺序草。螺序草属的种子形态特征对属下类群的划分具有重要的参考价值。 相似文献
16.
J. G. Rohwer 《Plant biology (Stuttgart, Germany)》1995,108(2):163-168
The fruit development in Menodora agrees largely with that in Jasminum, except for the final stages. The seed coat resembles that of Jasminum in the presence of ribbon-shaped wall thickenings in the mesotestal layers, a character not known from any other Oleaceae. In several characters there is more similarity between Menodora and Jasminum sect. Alternifolia, or between Menodora and J. nudiflorum, than there is among the species of Jasminum. This supports the idea that Jasminum might be paraphyletic, if Menodora is retained as a separate genus. 相似文献
17.
Zhang Zhi-Yun 《植物分类学报:英文版》1990,28(4):294-298
In the present paper pollen grains of 5 species and seed coat of 4 species of the
genus Cistanche (Orobanchaceae) from China were examined by scanning electron microscope
As a result, two types of the pollen exine sculpture are distinguished: (1) tuberculate, C. salsa
and C. lanzhouensis; (2) rugulate or fine reticulation formed by the fusion of rugae, C.
sinensis, C. deserticola and C. tubulosa. Chinese Cistanche was classified into two sections
based on the gross morphology by the present author (Zhang, 1984). C. lanzhouensis and
C. sinensis were included in one section. This classification is in conflict with the pollen type,
which indicates that the characters of pollen grains and external morphology in this genus have
evolved at different rates. The differences in pollen morphology of Chinese Cistanche can serve
as characters for delimitating species.
According to our abservation, C. lanzhouenis Z. Y. Zhang differs from the other members
of Cistanche not only in external morphology but also in pollen morphology. Pollen grains
are subprolate in this species, while prolate in the other four species, and exine sculpture is
tuberculate. The present study provides the establishment of this new species (Zhang, 1984)
with palynological evidence.
The seed coat sculpture in Chinese Cistanche are constantly alveolate, but there are some
slight differences, by which the sculpture can be divided into two types: (1) testa cells have
or have not thickenings on the inner anticlinal walls; cavernulous sculpture is present on
outer periclinal wall of some cells: C. sinensis; (2) testa cells have striate thickenings on the
inner anticlinal walls: C. salsa, C. deserticola and C. tubulosa. The characters of seed coatof some significance for the delimitation of species. 相似文献
18.
Na-Na LIN Hong WANG De-Zhu LI Stephen BLACKMORE 《植物学报(英文版)》2005,47(9):1036-1046
The pollen morphology of 28 species and one variety representing eight genera of the subtribe Mutisiinae Less. sensu Bremer (Compositae) was investigated by scanning electron microscopy (SEM) and light microscopy. The pollen grains are usually radically symmetrical, isopolar, and tricolporate. The shape varies from spheroidal to subprolate in equatorial view and is three-lobed circular in polar view. Based on exine sculpturing observed under SEM, the pollen grains can be divided into three types: (i) type Ⅰ, with macrogranulate sculpture; (ii) type Ⅱ, with a finely granulate sculpture; and (iii) type Ⅲ with spiny sculpture. The palynological data showed that the Macroclinidium Maxim. was remarkably distinguished from those of the other seven genera. The variation of pollen characteristics within the Mutisiinae in Asia is little at species level, but it proves some useful information for studying the relationships among genera and it has an important significance in further understanding the evolutionary history of Mutisiinae. 相似文献