The Basic Types of Flowers of Chinese Gramineae and Their Systematic Relevance

The flowers of the representative species of 33 tribes and 174 genera were investigated for the purpose of Gramineae systematics. Discussed in this paper are ten important flower characters, 6 of which are of the pistil, two of the androecium and two of the lodicule. The morphology of lodicules is of particularly great value in systematics, it consisting of nine forms: membranous-flattend, tongue-shaped, chaffy-peltate, hooded or helmet-shaped, spade-like, longitudinally folded, cucullate, top-shaped and funnel-thaped. Its numbers per flower may be: numerous, triple, dual, single and absent. On the basis of these ten characters, three major types and seven subtypes of the flowers of Gramineae may be recognized: Bambusoid (including True Bambusoid, Oryzoid, Arundinoid, Stipoid), pooid (with Subtype Pooid only) and Panicoid (including Eragrostoid, True Panicoid). As a result, The major groups corresponding to the flower basic types agree wih those divided according to the basic types of seedlings and caryopses. They are seven subfamilies: Banbusoideae, Oryzoideae, Arandinoi deae, Stipoideae, Pooideae, Eragrostoideae and Panicoideae.     

The Basic Types of the Seedling of the Chinese Gramineae in Relation to Systematics

Investigations have been made on the mode of development and various characteristics of seedling of 203 grass species representing over 76 genera and 22 tribes. The correlation between important characteristics and their main formative conditions in distribution area and habitat were discussed. According to the various developmental forms of the embryo axis and root system, the seedlings of grasses may be divided into three main types: Bambusoid, Festucoid and Panicoid. And according to characteristics of seedling leaves and adventitious roots, these types may be further divided into seven subtypes: True Bambusoid, Oryzoid, Arundinoid, Stipoid, Festucoid, Eragrostoid and True Panicoid. in this study, the different types of seedlings have been found to be associated with other characteristics of embryo and adult plant; and on these grounds, the genera of the Gramineae are grouped into seven corresponding subfamilies: Bambusoideae, Oryzoideae, Arundinoideae, Stipoideae, Festucoideae, Eragrostoideae and Panicoideae.     

The structure of the cells of the mesophyll and parenchymatous bundle sheath of the Gramineae

By a comparison of the ultrastructural features of the parenchymatous bundle sheath and the mesophyll it can be shown that the grasses can be divided into a number of groups roughly corresponding to those proposed by Brown, viz. Pooid, Eragrostoid, Panicoid, Arundinoid, Bambusoid and Aristidoid. In particular the ultrastructural features strengthen the grounds for separating the eragrostoid type of leaf anatomy from the panicoid type. These ultrastructural differences seem to be correlated with differences in photosynthetic pathways, and, where they do not correlate with the taxonomic divisions, neither do the photosynthetic pathways. The correlation with a taxonomy based on microcharacters as well as macroscopic characters is generally good except in the case of "Phragmitiform" grasses, and in particular the tribe Danthonieae, which seems to require a serious detailed extensive investigation.     

禾本科叶片表皮结构细胞的组合式样及其分类学意义

利用光学显微镜,对禾本科204属373种植物的叶片表皮进行了观察。发现禾本科叶片表皮细胸细胞在下表面上的分布式样可以划分为5个基本类型,即竹型、稻型、黍型、虎尾草型和早熟禾型,而5个基本类型所附属的植物类群分别是禾本科中的竹亚科、稻亚科、虎尾草亚科早熟禾亚科。同时分析了这5个类型的演化水平,并同类群的外部形态、地理分布相印证,表明竹亚科最原始、稻亚科次之、黍亚科演化居中、虎尾草亚科较高级、早熟禾亚科最高级;禾本科可能起源于世界的热带区域。     

Caryopsis morphology of the Chloridoideae (Gramineae) and its systematic implications

Macro- and micromorphological analysis of the caryopses of 58 taxa belonging to 45 genera of Chloridoideae allows the recognition of three caryopsis types according to differences in ventral face and hilum morphology. First is the convex ventral face, corresponding with a leaf-shaped hilum, observed in the tribe Pappophoreae. Second is the flat ventral face, corresponding with a rudimentary, needle-shaped or oblong hilum, observed in the tribes Eragrostideae and Leptureae. The third type, observed in the tribe Cynodonteae, is the concave ventral face, corresponding with a grooved or triangular hilum. The ventral face and hilum, together with other useful caryopsis characters, including six different shapes, seven types of spermoderm sculpture and three types of stylopodium, may be used as diagnostic characteristics of genera, and even species, in Chloridoideae. A key to identify the different species of 45 genera is provided.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 57–72.     

Nonstructural carbohydrates in dormant and afterripened wild oat caryopses

Nonstructural carbohydrates were determined in both embryo and endosperm of dormant (nongerminating) and afterripened (germinating) intact caryopses of wild oat ( Avena fatua L.). No changes in endosperm starch or soluble sugar were observed at the onset of germination (18 h). No changes in glucose, fructose, sucrose or starch within dormant or afterripened embryos correlated with onset of visual germination. In afterripened embryos, depletion of raffinose (18 h), stachyose (18 h) and galactose (24 h) was correlated with germination. In contrast, raffinose-family oligosaccharide levels in dormant embryos remained constant for 7 days following imbibition. Germination of isolated dormant embryos on 88 m M galactose-containing media was accompanied by decreased endogenous levels of raffinose and stachyose. Isolated embryos from dormant caryopses incorporated ¹⁴C from ¹⁴C-fructose into both raffinose and stachyose during 24 h of imbibition. In contrast, no ¹⁴C incorporation into stachyose was observed in embryos from afterripened caryopses. No ¹⁴C incorporation into raffinose was observed at 18 and 24 h. When in vitro activities of α galactosidase were measured, no temporal differences between dormant or afterripened caryopses were detected in either embryo or endosperm tissue. Although the mechanism associated with differences in utilization of raffinose and stachyose is yet unidentified, alterations in raffinose-family oligosaccharide metabolism in the embryo appear to be a unique prerequisite for afterripening-induced germination.     

中国壳斗科栎亚科花粉形态研究

本文应用光学显微镜与扫描电子显微镜观察了壳斗科所属栎亚科2属26种2变种的花粉形态,并以本科其它属一些代表种作对比,试图从孢粉学方面为栎亚科的系统分类提供依据。 花粉外壁纹饰在扫描电镜下可分三种类型,即水青冈型(含水青冈属),栎型(含栎属和三棱栎属),栗型(含栗属、锥属和柯属),花粉的类型与植物形态分类的三个亚科一致。 栎亚科的花粉外壁纹饰在扫描电镜下为颗粒聚集成的种种形状。栎属可区分为四种类型,即颗粒状、颗粒——蠕虫状、聚颗粒及芽孢状,其中类型一、二、三为常绿种类,类型四为落叶种类。花粉纹饰在常绿与落叶种类之间有较明显的差异,而青冈亚属和栎亚属之间却没有界线。因此,栎属仍以包含两个亚属为宜。三棱栎属花粉纹饰则介于栎属的类型二与三之间。     

Morphology and Germination of Yellow and Brown Caryopses of Aegilops Geniculata Roth (Gramineae) Population from Italy

Abstract

The germination percentage of Aegilops geniculata Roth caryopses was studied on four Italian populations (Pisa, Manfredonia, Catania and Simbirizzi). Observation of the germination trend was carried out at constant temperatures of 10°, 20° and 30°C, from maturation up to 60 days after harvesting. Spike, spikelet and caryopsis phenotypic characteristics were also studied. The populations of Pisa, Manfredonia and Simbirizzi presented two different types of caryopses: yellow caryopses - larger, heavier and composing roughly 60% of total—and brown caryopses—smaller and lighter in weight. The Catania population formed an exception in that brown caryopses were virtually absent (5%). This Sicilian accession also showed the largest spikelet size.

Yellow caryopses germinated more rapidly than the dark ones, which were shown to be endowed with longer relative dormancy, above all at 10° and 30° C. Such a phenomenon allows the two types of caryopses to have a different germination ecology, thus providing A. geniculata with a broader choice of germination opportunities and consequently favouring spread and survival of the species.     

The Morphological and Anatomical Characters of Bamboo Fruits with Relation to Systematics and Evolution

The morphological and anatomical characteristics of bamboo fruits of 39 species in 21 genera have been surveyed. The results showed that characters as the shape, the middle cross section, the morphology of pericarp, rostrum and embryo, the presence or absence of ventral groove and embryotega, and the thickness of aleurone layer of fruits were the important features in identifying different genera, and also in studying systematics and evolution of the bamboos. All the bamboo fruits examined herewith could be considered as caryopses, and they could be subdivided into four types viz. typical, bacoid, nucoid and seminucoid type. Type A,typical,as most grass fruits, with thin pericarp throughout or thickened only at apex, ventral groove (hilum) and embryotega, was found in the majority of bamboos, such as Fargesia and Arundinaria. Type B, bacoid, with thick and fleshy pericarp, was found in nine genera: Melocanna, Dicochloa, Ochlandra,Olrneca, Melocalarnus, Chirnonobarnbusa ,Qiongzhuea, Ferrocalamus and Alvirnia. Type C, nucoid, with hard pericarp, was found so far only in Dendrocalamus and Cephalostachyurn. Type D,semi-nucoid, the intermediate type between type A and C, with pericarp, as in type A, in the dorsum and pericarp, as in type C in the ventrum was found in Sinocalarnus, PhyUostachys and Thyrsostachys. Bacoid may be the primitive type, from which nueoid may have evolved. Semi-nucoid may have evolved from nucoid. Typical type may be advanced and have evolved from bocoid or semi-nucoid. The primitive fruits of bamboos may have characteristics such as follows: globose or spheroidal in shape, round middle cross section; thick and fleshy pericarp throughout, less differentiated, presence of vascular bundle; absence of ventral groove (hilum) and embryotega; aleurone layer composed of a number of cell layers; large and curved'or folded embryo. Bamboos with such a fruit have iterauctant inflorescences except Ferrocalamus.     

Pollen Morphology of Eight Genera of the Subtribe Mutisiinae Less. sensu Bremer (Compositae) from Asia

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.     

Pollen Morphology of Eight Genera of the Subtribe Mutisiinae Less. sensu Bremer （Compositae） from Asia

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.     

Participation of the tightly-bound (putative cytoskeleton-bound) polysomes in translation during germination of dormant and non-dormant cereal caryopses

Research was done on dormant and non-dormant barley cv. Ars caryopses and triticale cv. Grado caryopses treated and non-treated with abscisic acid (ABA). During germination higher participation of populations of so-called tightly-bound polysomes (TBP) in embryos of dormant barley caryopses was observed, as well as their high metabolic activity. In embryos of triticale caryopses of which dormancy was imposed in an artificial way by ABA (100 microM), the strongest incorporation of 14C-amino acids into nascent polypeptide chains in vivo was found in population of TBP, as well as the highest participation among three of the studied fractions (free polysomes, membrane-bound polysomes and tightly-bound polysomes). These results may indicate the significant role of TBP (putative cytoskeleton-bound polysomes--CBP) in maintaining dormancy during imbibition of cereal caryopses.     

Possible involvement of the cytoskeleton in the regulation of barley caryopsis dormancy and germination

This study was conducted on barley cv. Ars. caryopses collected at full ripeness and divided into two batches. From one batch (dormant caryopses) polysomes were isolated from embryos immediately after harvesting and after two days of germination. From the other batch (non-dormant caryopses) the same was done after eight months storage in a dry state. A low ionic strength cytoskeleton-stabilizing buffer was used for the isolation of polysomes. Four different fractions of polysomes were examined: free polysomes (FP), membrane-bound polysomes (MBP), cytoskeleton-bound polysomes (CBP) and cytoskeleton-membrane-bound polysomes (CMBP). In germs grown from non-dormant caryopses, the first two fractions (FP + MBP) made up about 78 % of the total ribosomal material, whereas in embryos of dormant, imbibed caryopses, two last fractions (CBP + CMBP) made up about 71 %. The percentage of polysomes after 48 hours of imbibition of dormant caryopses in the FP, MBP and CBP was only about 13 % (i.e., 87 % monosomes), whereas a greater proportion (19.4 %) was found in the CMBP. The highest incorporation of ³H-uridine and ¹⁴C-amino acids (after 48 hours of germination and 0.5, 3 and 6 hrs incubation with precursors) took place in trhc CMBP both in dormant and non-dormant caryopses The major amount of the two polysome fractions associated with the cytoskeleton (CBP and CMBP) and the higher activity of CMBP in protein synthesis in embryos of dormant, imbibed triticale caryopses may indicate a significant role for polysomes associated with the cytoskeleton in the control of protein synthesis in dormant and germinating caryopses.     

A Study on Pollen Morphology and Ultrastructure of Subfamily Castaneoideae (Fagaceae) in China

The present paper describes the pollen morphology of 45 species of the subfamily Castaneoifeae (including genera Castanea, Castanopsis and Lithocarpus) from China. The pollen grains were all examined with light microscope, scanning electron microscope and transmission electron microscope. Pollen grains of the subfamily are prolate, subprolate or perprolate, (14.7-23.1)× (8.4 -18.9) μm in size, 3-colporate, the exine in 2-layered, 0.9-1.9μm thick, indistinctly ornate, striate-rugulose or crass-striate, sexine and nexine almost equal in thickness, the sexine consists of tectum, bacules and endonexine under TEM. On the basis of very similar pollen shape, pollen size, type of aperture and exine structure and also other characteristics of plant morphology of the genera Castanea, Castanopsis and Lithocarpus, the present authors tend to support the opinion that they all fall into the samesubfamily, Castaneoideae.     

Pollen morphology of the tribe Rhinantheae (Orobanchaceae) and its systematic significances

Pollen morphology of 36 species representing 14 genera within the tribe Rhinantheae in the family Orobanchaceae was studied and illustrated with light microscopy (LM) and scanning electron microscopy (SEM). Five major pollen types were recognized on the basis of exine ornamentation. Within these major types, minor types (subtypes) were distinguished based on exine surface pattern, size, shape, amb form, colpi and colpus membrane. These types and subtypes are as follows: type I. retipilate: subtype Ia. regular retipilate: (1) pollen size < 27 μm, (2) pollen size > 27 μm, subtype Ib. irregular retipilate; type II. verrucate: subtype IIa. macro-verrucate, subtype IIb. verrucate, subtype IIc. sparse verrucate; type III. retirugulate; type IV. granulate; type V. micro-reticulate. A key to pollen morphology of genera studied within the Rhinantheae was made based on pollen morphology from our study and earlier work. Combining with other sources of information on the Rhinantheae, the systematic relationships of this tribe are discussed. Rhinantheae pollen displays considerable variation between genera and species, with taxonomically significant characters at genus and species level. Palynological characteristics provide evidence for interpreting the conflicting views concerning the “Pterygiella Complex”. The evolutionary trend in exine sculpture of Rhinantheae could be proposed, namely that retipilate sculpturing which is the most widespread type is more primitive than the other types (such as foveolate, granulate, regulate, reticulate, retirugulate and verrucate). The pollen data in present study and the view of Hong (1986), as well as the molecular data from Bennett and Mathews (2006) indicated that Asia and related regions were likely to the origin centre of the tribe Rhinantheae.     

穇属颖果微形态及其系统学意义

在电子扫描显微镜下观察了穆属(Eleusine Gaertn.)9种植物颖果的微形态特征.结果表明,穆属颖果有卵形、披针形和矩圆形3种腹面形状,压扁方式有背腹压扁及两侧压扁,腹面形态有平腹面和凹腹面两种,胚比为0.29～0.58,种脐比为0.10～0.24,颖果纹饰有2种,包括疣突状一级纹饰和疣突规则排列构成的复合网状...     

中国独行菜族部分属种的叶表皮观察

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。     

Pollen Morphology of Plumbaginaceae in China

The present paper describes the pollen morphology of 30 species belonging to 7 genera of Plumbaginaceae from China. The pollen grains were all examined under light microscope, and those of some species under scanning and transmission electron microscope. The pollen grains of the family are subspheroidal, prolate or oblate, (37.5-74.5)× (40.4-81.9)μ in size, 3-colpate, rarely 4-6-colpate, only pancolpate in Ceratostigma willmottianum. The exine 2-layered, 2.0-7.4μ thick, sexine thicker than nexine, verrucate, reticulate or coarsely reticulate. On the basis of the morphology, two types of pollen grains are distinguished in the family: (1) The pollen grains are 3-(rarely 4-6 ) or pancolpate, the exine verrucate. They are found in the tribe Plumbagineae (inculuding the genera Ceratostigma, Plumbago and Plumbagella). (2) The pollen grains are all 3-colpate, the exine reticulate or coarsely reticulate. They are found in the tribe Staticeae (including the genera Acantholimon, Ikonnikovia, Goniolimon and Limonium ).     

Seedling morphology in Genisteae (Fabaceae) &om south-west Spain

The morphology of the seedlings of 30 taxa belonging to the tribe Genisteae (Fabaceae) from the Iberian Peninsula has been studied to determine morphological features of taxonomic value in this developmental phase. These characters do not segregate taxa but can be used to separate them into groups. Subtribes Genistinae and Lupininae can be distinguished by median seedling size and the shape and size of the cotyledons. In the same way, the number of leaflets, the presence or absence of foliar stipules, and the existence of foliaceous or fleshy cotyledons, provide characters to describe six seedling types for the tribe Genisteae— Gaistu, Atgyrolobium, Cytisus, Retama, Adenocarpus and Lupinus —each including several taxa. It is also concluded that, at the generic level, only Retama, Lupinus and to some extent Adenocarpus can be distinguished from their seedling characteristics; the other genera have a set of morphological features that do not allow such a segregation.     

Redundancy modulation of nuclear DNA sequences in Dasypyrum villosum

In order to assess fluid domains in the genome of Dasypyrum villosum, Feulgen/DNA cytophotometric determinations and molecular and cytological DNA-DNA hybridization experiments were carried out in resting embryos and developing seedlings from yellow and brown caryopses belonging to different populations. The cytophotometric data showed that the basic amount of nuclear DNA is, on average, 12% higher in 2-day-old seedlings from yellow caryopses as compared to those from brown caryopses. It increases in each individual during seed germination, to a higher extent in seedlings from yellow caryopses than in those from brown caryopses. DNA content also differs up to 13% between plants within a caryopsis-colour group and up to 40% between populations. Dot-blot hybridization of a 396-bp D. villosum-specific DNA repeat to genomic DNA extracted from embryos in dry seeds, or from seedlings belonging to single progenies of plants from different populations, confirmed the cytophotometric results. The redundancy in the genome of sequences hybridizing to the 396-bp element differs significantly both between populations and between plant progenies within a population. During seed germination these sequences are the more amplified the less they are redundant in the genome of resting embryos, and amplification occurs to a significantly-greater extent in seedlings from yellow caryopses than in those from brown caryopses. ³H-labelled 396-bp sequences hybridize at or near the telomeres of most chromsome pairs though only to the shorter of the two subtelocentric pairs. The hybridization level is higher in seedlings from yellow caryopses that in those from brown caryopses, and a linear correlation exists between the number of silver grains counted over the labelled regions of each chromosome pair in the two groups of seedlings. Possible control mechanisms of the observed changes in the nuclear genome, and the role of these changes in developmental pregulation and environmental adaptation, are discussed.