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1.
Kengyilia melanthera (Keng)J. L. Yang, Yen et Baum and K. kokonorica (Keng)J. L. Yang, Yen et Baum are two hexaploid perennial grasses of the tribe Triticeae native in west China. K. melanthera and K. kokonorica were hybridized with Roegneria kamoji Ohwi(2n=42,StStHHYY) and K. hirsuta (Keng)J. L. Yang, Yen et Baum (2n = 42, PPStStYY) respectively. Chromosome pairing behaviour at metaphase I in the parents and hybrids was studied. Meiotic configurations were 18.20 Ⅰ + 11.74 Ⅱ + 0.09 Ⅲ + 0.01V for R. kamoji×K. melanthera, 1.06Ⅰ + 20.47 Ⅱ for K. hirsuta×K. melanthera, 19.36Ⅰ + 11.26 Ⅱ + 0.04Ⅲ for R. kamoji×K. kokonorica, and2.46Ⅰ + 19.44Ⅱ + 0.14 Ⅲ + 0.06 Ⅳ for K. hirsuta×K. kokonorica. Considering chromosome pairing in the hybrids, as well as morphological characters, K. melanthera and K. kokonorica should be grouped in Kengyilia Yen et J. L. Yang instead of being keeped inRoegneria sect. Paragropyron Keng , or in Elymus L. or Elytrigia Desv.  相似文献   

2.
Spores of 61 species and 6 varieties in 9 genera of the Sinopteridaceae were examined under scanning electron microscope (SEM). Based on surface ornamentation and other features, the spores of the Sinopteridaceae are divided into three types. In type Ⅰ , the exospore is smooth and the surface ornamentation, which is reticulate, cristate, echinate or rugate, is formed by the perispore. All the other genera of this family, except for Onychium and Cryptogramma, have this pattern of spores. In type Ⅱ, the surface ornamentation is formed by both perispore and exospore. This pattern is found only in Cryptogramma. In type Ⅲ, the perispore is thin and the surface ornamentation is formed by the exospore. Onychium is characterized by this type of spores. Those genera with spores of type Ⅰ of the Sinopteridaceae seem to be closely related to each other and should be natural members of this family. The systematic position of Cryptogramma and Onychium, with spores of type Ⅱ and type Ⅲ respectively, however, should be reconsidered. Aleuritopteris might be the mostprimitive member of the Sinopteridaceae from the evidence of spore morph  相似文献   

3.
Macro- and micro-morphological characteristics of fruits in eight species and one variety of the genus Fagopyrum Mill. (Polygonaceae) from China were observed under stereoscope and scanning electron microscope(SEM). Based on the results, the fruits of the species studied are divided into type Ⅰ , Ⅱ and Ⅲ. The fruits of type Ⅰ are triangular-pyramidal; their surface are rugosely reticulate, neither smooth nor shiny. Two species, F. tataricum and F. dibotrys have this fruit type. Those of type Ⅱ are ovoid-triangular-pyramidal; their surface are smooth and shiny, and striately reticulate. Three species, F. esculentum, F. statice and F. lineare, have this fruit type. In type Ⅲ, the fruits are ovoid-triangular-pyramidal; their surface are smooth and shiny, and covered with many warty grains and sparsely finely striate. F. urophyllum, F. gracilipes, F. leptopodum var. leptopodum, and F. leptopodum var. grossii have this fruit type. Judging from the morphological characteristics of fruits, F. dibotrys might be more closely related to F. tataricumthan to F. esculentum.  相似文献   

4.
The structure, type, morphology and location of secretory structures in leaves of 43 species, 1 subspecies and 1 variety of 9 sections in Hypericum L. were comparatively studied using tissue clearing, paraffin sectioning and thin sectioning. The results have shown that the presence of secretory structures is a common feature of leaves in this genus. According to their anatomical characteristics, the secretory structures can be divided into nodules, secretory cavities (canals) and tiny secretory tubes. In their distribution in leaves the nodules fall into two types: the leaf edge type and the scattered type. According to the location of cavities in the cross sections of leaves, the cavities can be divided into 4 types: the median type which is situated between the palisade tissue and spongy tissue, the palisade tissue type, the spongy tissue type and the across-mesophyll type. Based on the location of cavities and nodules in leaves, the species in Hypericum can be divided into 3 groups: group Ⅰ , in which only cavities are present; group Ⅱ, in which only nodules are present; group Ⅲ, in which both cavities and nodules are present. The type, location, distribution density and morphology of secretory structures are of some taxonomic value at the level of species and of section in Hypericum L. From these observations, the evolutionary trends concerning the morphology and anatomy of secretory structures and the affinity among sections in the genus Hypericum ate dis-cussed.  相似文献   

5.
The ultrastructure of developing and mature mucilage idioblastsin the shoot apex and leaves of Cinnamomum burmanni and Cinnamomumverum (Lauraceae) is described. In all mucilage cells a suberizedlayer is present in the outer cellulosic cell wall from a veryearly stage in development onwards. This represents the firstultrastructurally documented record of a suberized wall layerin mucilage cells. Oil cells, the other type of secretory idioblastsin Lauraceae, commonly have subenzed wall layers, and the presentresults support suggestions of a possible homology of oil andmucilage cells in the so-called primitive angiosperms Suberized layer, mucilage idioblasts, Cinnamomum burmanni  相似文献   

6.
In order to investigate morphological variations of Elymus sibiricus L., E. nutans Griseb., and E. burchan-buddae (Nevski) Tzvelev [=Roegneria nutans (Keng) Keng], and to explore their systematic relationships, six morphological characters were measured and compared between the Elymus species. Interspecific hybridizations between E. nutans and E. sibiricus, and E. burchan-buddae were carried out with the aid of embryo rescue. Chromosome pairing behaviour was also analysed at metaphase- I of meiosis in pollen mother cells of F1 hybrids. Morphologic characters, such as length of spikes and length of glumes varied considerably between different individuals of each species, whereas length and width of paleas were quite stable and different between species. The interspecific hybrids were completely sterile and their meioses were irregular. Meiotic configuration of E. nutans × E. burchan-buddae was 7.70I +13.40Ⅱ+0.06Ⅲ+0.08 IV, whereas that of E. sibircus×E. nutans was 11.98I+9.61Ⅱ+0.64Ⅲ+0.39Ⅳ+0.01V. It is concluded from the morphological and cytological study that (1) it is possible to identify the three Elymus species using the palea character, in addition to other traditionally applied characters; (2) Elymus nutans and E. burchan-buddae have a comparatively high genomie relationship, while E. nutans and E. sibircus have a relatively low genomic affinity to one another; and (3) a certain chromosome pairing regulator was presented in the hybrid between E. burchan-buddae andE. nutans.  相似文献   

7.
Spore morphology of 51 species of Cyclosorus in the Thelypteridaceae from China was investigated using scanning electron microscopy (SEM). The spores are monolete, bilaterosymmetric, ellipsoidal in polar view, and kidney-shaped in equatorial view. On the basis of the variation in their surface ornamentation, the spores fall into three main types. Type I: The surface of spores is echinate or perforate with fimbriate wings. 19 species belong to this type. Type Ⅱ: The surface of spores is cristate. 11 species belong to this type. Type Ⅲ: The surface of spores is echinulate. 10 species belong to this type. The remaining 11 species have spores with mixed surface ornamentation of the above three types, which are considered as intermediate types. The results are valuable for a better understanding of the taxonomy and palynology of the genus Cyclosorus.  相似文献   

8.
黄红慧  李景照 《广西植物》2018,38(2):210-219
该研究对地质时期樟科植物花化石的主要类群,即Androglandula、Lauranthus、Mauldinia、Neusenia、Perseanthus和Potomacanthus属分别从属和种的形态特征、分布、地层以及系统意义进行了论述,并结合现代樟科植物从地层和分布、花序类型、花部形态特征和显微构造特征进行了分析。结果表明:(1)樟科植物在中晚白垩纪期,已经起源于劳亚古陆的中纬度区域。(2)樟科植物的花序类型为Mauldinia属的侧生花序类型和假伞形花序类型。(3)花为3基数的两性花,花被片6枚排列为2轮,雄蕊12或6,排列为4、3或2轮,最内轮雄蕊不育,第三轮雄蕊基部常见一对附属腺体,雄蕊药室瓣裂,4或2药室,雌蕊为单心皮。(4)花被片上常有大量的油细胞、并列型气孔器和单细胞毛。该研究结果中樟科花化石的发现,为樟科植物的系统演化提供了古生物学的证据和资料。  相似文献   

9.
The intergeneric hybrids between Roegneria kamoji Ohwi and Dasypyrum villosum (L.)Candargy were successfully obtained by means of embryo culture in vitro. Studies on morphology, fertility and chromosome pairing behavior in meiosis of the parents and their hybrid Fl were carried out in the present work. The results showed that: (1) there were ob vious morphological differences between R. kamoji and D. villosum, and spikes of Fl plants were morphologically intermediate between the two parental species; (2) the seed set of the cross was 11.63%; the hybrid plant was infertile, which indicated that strong repro ductive isolation existed between the parents and R. kamoji and D. villosum were inde pendent biological species; (3) The somatic chromosome number in root-tips of Fl hybrids was 28. Chromosome pairing at MI of PMCs in Fl hybrids was quite low. The meiotic con figuration was 26.72 Ⅰ + 0.62 Ⅱ + 0.02 Ⅲ, which indicated that very low homoeology was detected between the St, H, Y genomes of R. kamoji and the V genome of D. villo- sum, and the relationship between the parental species was remote.  相似文献   

10.
Anatomical characters of leaves of Chinese species of the tribe Thermopsideae, including 3 genera and 13 species, were compared. The results show that the differentiation of mesophyll cells, stomatal types, stomatal distribution and density, shape of epidermal cell, trichome shape and density, cuticular membrane and waxy ornamentation have important systematic and ecological significance among the genera of the tribe. With regard to leaf architecture, pollen morphology and external morphology studies, we suggest that Ammopiptanthus represents an isolated and primitive genus in the tribe and Piptanthus is closely related to Thermopsis. Although different vein-endings, stomatal types and trichomes indicate systematic differences, other characters, such as mesophyll type, stomatal distribution, trichome density etc. are the result of ecological adaptation among the genera. Results of the present study confirm our previous conclusion that two evolutionary trends exist in the tribe, the first towards xerophilization and the second towards cold-adaptation They are caused by the desertification of the central Asian area and the heave of intermountainous plateau. Ecological isolation may be a main evolutary motivation among the taxa in the tribe. We have obs'erved that stomatal density and size in the xeromorphic genus, Ammopipianthus, are not simply a result of the general trend in xerophytes to have high stomatal density correlating with the relatively small size. On the contrary, stomata in this genus are larger than those in the mesophytic genus, Piptanthus, and the density on the lower surface is much less than in the latter. However, stomatal density on the upper surface follows the trend in concordance with increasing aridity and altitute.  相似文献   

11.
Spore morphology of thirteen species of the genus Bryum Hedw. were observed by LM and SEM. The results show that the ornamentation of spore exine could be divided into three types: Type I , blunt at the top of baculate processes, to which four species belong: Bryum argenteum, B. lonchocaulon , B. uliginosum and B. arcticum. Type Ⅱ, sharp or with small processes at the top of baculate processes, represented by seven species: B. pallescens, B. caespiticium, B. pallens, B. pseudotriquetrum, B. paradoxum, B. alpinum and B. thomsoii. Type Ⅲ, expanded into hemispherical-shaped at the top of baculate processes, represented by two species: B.coronatum and B.sauteri. The Bryum species may also be divided into three groups according to the variation of spore diameter. Group I , with spore diameter under 10 μm, including one species, B. uliginosum. Group Ⅱ, with spore diameter 11~20 μm, including seven species: B. argenteum, B. alpinum, B. coronatum, B. pallens, B.paradoxum, B.sauteri, B.thomsonii. Group Ⅲ, spore diameter 21~30 μm, with five species: B. pallescens, B. caespiticium, B. pseudotriquetrum, B. lonchocaulon, B. arcticum. There are resemblances of spore morphology and exine ornamentation among the thirteen species. In the view of palynology, the genus Bryum is a natural taxon which is more advanced than the genus Pohlia Hedw. But spores of thirteen species are different at some characters such as diameter, shape ofproximal leptoma, etc., which indicates the genetic differentiation in the genus Bryum.  相似文献   

12.
油樟油细胞和粘液细胞的发育解剖学研究   总被引:2,自引:0,他引:2  
利用薄切片法对油樟茎叶油细胞和粘液细胞发育的研究结果表明,油细胞最早发生于第二叶原基以及茎端皮层和髓的基本分生组织中。未出现油细胞以前,在上述器官的基本分生组织和原分生组织中,难以区分油细胞的原始细胞与周围细胞,当油细胞原始细胞呈现出体积较大,液泡化程度较低,细胞核大而明显的特征才明显可辨,以后经过液泡融合,油细胞成熟和油细胞的细胞质解体阶段而成为一贮油的囊,而且油囊连接在杯形构造上,粘液细胞的早期发育过程与油细胞的相同,而在细胞液泡化的后期,靠近大液泡的细胞质中产生粘液物质。并扩散到大液泡中,粘液物质不断产生,变浓,占据整个细胞腔,细胞质解体后而成为完全成熟的粘液细胞,因此可见,油细胞和粘液细胞是同源的,也可能粘液细胞是由油细胞转化而来的。  相似文献   

13.
This study aims to determine whether morphoanatomical characters of the leaves of the species of Chamaecrista sect. Absus subsection Baseophyllum could be used to support an up-ranking of C. cytisoides varieties to the species level as previously defined by molecular studies. The significance of anatomical adaptive strategies to arid environments is also discussed. Standard light microscopy techniques and histochemical tests were used for both morphoanatomical and histochemical characterization of the leaves. All the species studied share a single-layered epidermis, actinodromous–camptodromous–brochidodromous type of venation, vascular bundles surrounded by layers of fibers bounded externally by a sheath of cells containing solitary crystals, enlarged tracheids at the vein endings, vascular petiole/rachis tissue with a parenchymatous pith, accessory vascular bundles, mucilage idioblasts and hypodermis in the mesophyll, colleters, and non-secretory trichomes. The position and type of stomata, type of mesophyll, number of palisade and spongy parenchyma layers, position of mucilage idioblasts in the mesophyll, and the number of accessory vascular bundles of petiole/rachis provided useful characters for discriminating the eight species of the subsect. Baseophyllum. Histochemical tests reveal the presence of total polysaccharides, pectins, mucilage and phenolic compounds in the idioblasts. Other xeromorphic characters such as thickened outer periclinal cell walls, compact mesophyll, mucilage idioblasts and hypodermis in the mesophyll may help enable the studied species to survive in exposed sunny areas.  相似文献   

14.
Cytological and biosystematic studies on the genus Pteris have made a great contribution to the theory of speciation and evolution in ferns. Sino-Japanese area is one of the speciation centers of this genus. But only a few Chinese species have been known cytologically. As a preliminary study, ten species of the genus Pteris and two species of the related genera Pteridium and Histiopteris were observed. All the materials were collected from southwest and south China. Their young sori were fixed in ethanol and glacial acetic acid (3:1), in the field. The preparations were made with acetocarmine squash method. The vouchers are deposited in PE. The results of observation are summarized in Table 1. Of Pteris, four species are agamosporous, eight are polyploid, six are actually the members of species complexes. Only two species are purely sexual diploids. Pteris cretica L. var. nervosa (Thunb.) Ching et S. H. Wu has 58 autobivalents at meiosis of spore mother cell, and usually produces 32 diplospores per sporangium. It is obviously an agamosporous diploid. Apart from 32-spored sporangium, some 4-, 8-, 16-, 64-, 13-, 34-, 36-spored, completely abortive or partly abortive sporangia were also found in the fixed material of a single individual. For explaining these unusual types of sporangia at least nine sporogenesis routes can be inferred. It may not be impossible that besides mainly producing functional diplospores, P. cretica var. nervosa also gives a few functional giant spores with a doubled or multiplied somatic chromosome number, which means that polyploids may be simply derived from the spores produced by their diploid parent. The spores in a sporangium are usually tetrahedral, but a few bilateral ones are also found in some sporangia. Sometimes, the bilateral spores are even more than the tetrahedral ones in a sporangium. Pteris vittata L. from the type locality shows 58 bivalents at diakinesis of meiosis. Without doubt, it is a sexual tetraploid, which was also found in south Guangdong and south Yunnan. However, Its natural ancestral diploid has been widely found in the subtropical regions of China, such as Sichuan, Guizhou, Yunnan and Hubei provinces. A sterile triploid with the chromosome number of n=201Ⅰ+26Ⅱ+5Ⅲ and a sterile tetraploid hybrid with the chromosome number of n=9Ⅰ+45Ⅱ+3Ⅲ+21Ⅴ were found in south Yunnan and south Guangdong respec tively. It is evident that P. vittata L. sensu lato is a species complex which includes several cy totypes. Its hexaploid form was reported from south India by Abraham et al. The distribu tion pattern of different cytotypes in P. vittata complex may indicate that the tropics is more favourable to formation and surviving of polyploid than the subtropics. However, it is most possible that Chinese subtropics is the origin place of the ancestral member in the P. vittata complex. In gross morphology, the tetraploid and triploid forms are only bigger and stronger than the diploid form. But the diploid can also grow rather big in cultivation. They can har dly be distinguished from each other. Therefore, they are not given formal names here. The author fully agree with Prof. T. Reichstein when he said in 1983 that it was hoped that a new nomenclature could be adopted for the cytotypes of species complex in future. The special chromosome number of Pteris deltodon Bak .was counted in this work for the first time. It has 55 bivalents at meiosis of SMC. This number is the only exception in the genus Pteris, and shows that aneuploidy may have taken place in this genus. However, the pos sibility can not be ruled out that P. deltodon is an allotetraploid came from two diploid species respectively with the chromosome number 26 and 29. Pteris gallinopes described by Prof. Ching in i983 is an agamosporous tetraploid with 116 autobivalents at meiosis, different from the related triploid species P. dactylina Hook. and P. henryi Christ. P. ensiformis Burm P. muftifida Poir. and P. semipinnata L. are sexual tetraploids with n=58. P. excelsa Gaud. and P. oshimensis Hieron. var. paraemeiensis Ching are agamosporous triploids with n = 87 autobivalents. P. wallichiana Agardh is a sexual diploid with n=29. The high frequency of polyploids and agamospory among these random sampled Chinese species futher confirms the conclusion that both polyploidy and apomixis have played an important role in speciation and evolution of the genus Pteris. Pteridium aquilimum (L.) Kunh var. latiusculum (Desv.) Underw. ex Heller and Histiopteris incisa (Thunb.) J. Sm. have n=52 and n=96 respectively. They are both sexual tetraploids. Their chromosome numbers show again that the genera Pteridium and Histiopteris are distinquished from the genus Pteris by different basic numbers. This project is supported by the National Natural Science Foundation of China.  相似文献   

15.
The leaf structure and morphology, the structure and location of oil cells in leaves of 82 species and 1 subspecies in 10 genera of the Magnoliaceae were comparatively studied using tissue clearing, paraffin sectioning and thin sectioning. In leaves of Liriodendroideae, some of abaxial epidermal cells are papillose and the vascular tissue of the main vein appeared to be separated. However, papillose cells were not found and there were uniseriate, multicellular or unicellular hairs distributed on the epiderm, and the vascular tissue of the main vein appeared to be continuous in leaves of the Magnolioideae. Furthermore, in the Magnolioideae, the structure of leaves of Manglietia were different from that of Magnolia. These results support the separation of Magnolioideae and Liriodendroideae, and suggest that Manglietia and Magnolia be independent genera, which is consistent with Law’ s taxonomic scheme. Oil cells are one of marked features of the leaf anatomy of the Magnoliaceae, and they are mainly distributed in the palisade tissue in leaves of 47 species and in the spongy tissue in leaves of 5 species, and dispersed in the whole mesophyll in leaves of 31 species. The size and location of oil cells in leaves, combined with the thickness of leaves, the number of layers of the palisade tissue, the ratio of palisade tissue to spongy tissue in thickness, the hypo-derm, and the type of hairs may be used as the characteristics of genera and even species.  相似文献   

16.
中国木兰科植物的叶结构及其油细胞的比较解剖学研究   总被引:13,自引:0,他引:13  
利用组织透明法、石蜡切片法及薄切片法对木兰科10属82种1亚种植物叶片的结构和油细胞的 分布密度、结构及其在叶肉中的分布进行了比较研究。鹅掌楸亚科和木兰亚科在叶结构上的主要区别是:鹅掌楸亚科两种植物叶的部分下表皮细胞乳突状,且整个细胞外壁只形成一个乳突,而在木兰亚科植物中有单列多细胞或单细胞的表皮毛,却未发现乳突;鹅掌楸亚科植物叶主脉维管组织环分隔呈束状,且其外包被的纤维也排列成束状,而木兰亚科的80种1亚种植物中,叶主脉维管组织连成轮状,其外面也由一圈连续的纤维环所包围。从而支持木兰科中木兰亚科和鹅掌楸亚科两个亚科的划分。并且,从叶主脉的演化趋势来看,鹅掌楸亚科较木兰亚科进化。另外,木莲属植物叶片的结构与木兰属具有明显差异,因而进一步证明木莲属是不同于木兰属的一个独立的属。油细胞是木兰科植物叶片解剖的显著特征,在叶肉中的分布可划分为3种类型:(A)主要分布于栅栏组织;(B)主要分布于海绵组织;(c)均匀散布于整个叶肉中。油细胞的大小及其在叶中的分布与叶厚、栅栏组织层数、栅栏组织与海绵组织厚度间的比值以及下皮层的有无、表皮毛的类型、叶脉的结构等特征相结合,可作为属、甚至种的鉴别特征。  相似文献   

17.
Mastroberti AA  Mariath JE 《Protoplasma》2008,232(3-4):233-245
The roles of mucilage cells were investigated through morphological and cytological analysis during leaf development in young Araucaria angustifolia plants. Differentiation began in leaf primordia in the shoot apex, when the young cells underwent a greater increase in volume in comparison with other mesophyll cells. The mucilage polysaccharides were synthesized by dictyosomes, from where they were taken by large vesicles and released into a cavity formed by detachment of the tonoplast, which was separated from the cytoplasm. At the end of differentiation, the cell was completely filled with mucilage, a gel consisting of a denser reticular structure surrounding less dense regions. The nucleus and cytoplasm were degenerated in mature cells. The A. angustifolia mucilage cells presented some cytological resemblances to the mucilage cells of members of some dicotyledonous families; however, differences in the dictyosomes and the secretion route were observed. Translocation and water storage of solutes was suggested by the use of the hydroxy pyrenetrisulfonic acid tri-sodium salt apoplastic tracer. The tonoplast detachment, dechromatinization, nuclear condensation, and general degeneration of the membrane systems observed during maturity indicated a programmed cell death process, one not yet described for angiosperm mucilage cells.  相似文献   

18.
The arbitrarily primed polymerase chain reaction(AP-PCR) technique was applied to the analysis of the phylogenetic relationships among species of Chinese Sagittaria except S. natans which is not included in this study. One hundred and twenty-seven polymorphism DNA fragments were generated by ten arbitrarily primers and used to calculate the genetic distance. A phylogenetic dendrogram was constructed based on genetic distance by UP-GMA method. The results show that Chinese Sagittaria can be divided into three groups, which are composed of seven species and three varieties or forms except S. natans. Thethree groups are: group I ,with only one species S. guayanensis; group Ⅱ ,composed of S. tengtsungensis, S. wuyiensis, S. lichuanensis and Segittaria sp.; group Ⅲ, S. potamogetifolia, S. pygmaea, S. trifolia var. trifolia, S. trifolia var. sinensis, S. trifolia f. longiloba. Results of the present study are congruent with those based on morphologi-cal and karyotypical ones.  相似文献   

19.
利用扫描电镜、叶表皮离析法和石蜡切片法研究了番荔枝科93种2变种植物叶片的形态结构.结果表明番荔枝科植物叶片形态结构具有较大相似性,如叶表面均具有表皮毛,表皮细胞具有晶体,气孔器为平列型,具2~6个副卫细胞,仅分布在远轴面,普遍具有败育气孔器,叶肉组织中普遍含有油细胞等,但表皮毛的类型,表皮细胞的形状,表皮细胞内晶体的类型和形态,叶肉组织的结构具有明显的属间和种间差异.  相似文献   

20.
WILKINSON, H. P., 1988. Leaf anatomy of the Menispermaceae tribe Tiliacoreae Miers . An anatomical study of the leaves of 25 species belonging to 12 of the 19 genera has been made. The anatomical characters found to be of the most use in distinguishing taxa or groups of taxa are: in surface view–stomatal outline, stomatal density and distribution, subsidiary cell or surrounding cell patterns, presence /absence of hairs; in transverse sections–dimensions of adaxial epidermal cells, morphology of spongy mesophyll, midrib outline, number and distribution of vascular bundles, presence/absence of an upper pulvinus, presence/absence of sclereids in the upper pulvinus, presence/absence of secretory sacs, crystal type and distribution.  相似文献   

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