Morphological and anatomical studies inTribulus terrestris I. Phyllotaxis and branching

Phyllotaxis and branching system inTribulus terrestris were studied. Besides three nodal types already known in the species, a new type was found. The four nodal types were designated as A (with one leaf and no flower), B (with one leaf and one flower), C (newly found type, with two leaves of different sizes and no flower) and D (with two leaves of different sizes and one flower). A-type nodes are found only in basal parts of shoots, while distal parts have exclusively D-type nodes. Between the nodes of the two types there is always one node of B-type. Occurrence of C-type is rare and restricted to the first node of the lateral branch. The first leaf of the lateral branch superposes to the leaves of the mother axis at maturity, but it is situated at first more or less laterally. On the basis of anatomy, as well as gross morphology, the branching system at B- and D-type nodes was interpreted as sympodial, the main axis ending in a flower. With regard to the manner of overlapping of sepal margins, right- and left-handed calyces were recognized. The handedness always corresponds to the direction to which the peduncle is inclined.     

弥勒魔芋珠芽发育过程的形态学和解剖学研究

珠芽是弥勒魔芋的一种重要营养繁殖器官。以弥勒魔芋为材料,通过形态学观察以及解剖学研究,揭示了弥勒魔芋珠芽形成过程中的一系列特征。结果显示:弥勒魔芋珠芽生长于植株叶柄分叉以及裂叶分叉处,由主干茎或主干叶柄表皮下的薄壁细胞重新获得分裂能力后分化而来。珠芽的发育过程可分为珠芽原基启动形成期,珠芽膨大期和珠芽成熟期。珠芽的生长终止于植株衰老倒伏。研究表明,弥勒魔芋的珠芽生长位点明显区别于其他常见植物,珠芽繁殖是魔芋适应生态环境的一种重要机制。     

Morphological and anatomical studies on fruits of Veronica from south-west Spain

Following examination by scanning electron and light microscope of the fruit features of 12 species of Veronica from south-west Spain, morphological and anatomical studies revealed that these taxa can be differentiated on the basis of these features. Phenetic analysis with 28 characters additionally revealed several groups of species in Veronica to be closely related on the basis of their seed morphology. A key distinguishing the different taxa is provided. Finally, dehiscence mechanisms are briefly discussed.     

Morphological, anatomical and palynological studies on Asyneuma michauxioides (Campanulaceae)

The morphological, anatomical and palynological features of Asyneuma michauxioides (Boiss.) Damboldt (Campanulaceae) were investigated. This species is an East Mediterranean Floristic Element and an endemic in Turkey. In anatomical studies, cross-sections of the root and stem were examined and demonstrated by photographs. It has conspicuous endodermis in which the Casparian bands are indistinct in the stem. According to the result of this study, it was found that pollen grain of this taxon was 3-porate sometimes 4-porate and oblate-spheroidal. Its structure was tectate and sculpture was small granules and pits with densely spaced spinules. The seeds of the taxon were eliptic to ovate in shape, laterally compressed, brown to light brown in colour, glabrous and shiny.     

4种药用芦荟叶的形态解剖学研究

通过植物形态解剖学方法研究４种药用芦蔡的叶的结构,结果表明：它们都具有早生多浆植物中的结构特征。表皮及角质层厚,气孔下陷,气孔下陷,孔下室大。叶肉分为二部分,由同化薄壁组织和储水组织组成。同化薄组织由多层细胞组成,细胞形态相似,不分化为栅栏组织和海绵组织。储水组织占据叶的体积一半以上,细胞大、不规则、壁薄、富含粘液。维管束具鞘,呈环状分布。紧靠同化组织的维管束赶忙皮薄壁组织发达,具有合成和储存芦荟     

绵枣儿花芽分化的形态解剖学研究

为探明绵枣儿(Barnardia japonica)在哈尔滨地区的年生长节律以及花芽分化进程,该文以从长白山引种至东北林业大学花卉研究所苗圃内的绵枣儿为材料,采用田间观察法研究绵枣儿的年生长节律,并采用石蜡切片法观察其花芽分化各阶段的形态解剖学特征。结果表明:(1)绵枣儿在哈尔滨地区的生长节律大致可以分为四个时期,即花芽分化与发育期、开花期、结实期、休眠期。(2)绵枣儿花芽分化进程可以分为七个阶段,即4月中上旬,由于土壤温度较低,鳞茎仍处于未分化期; 4月下旬进入花序原基分化期; 5月上旬苞片原基分化; 5月下旬为小花原基分化期; 5月末至6月初花被片原基分化; 6月上旬进入雄蕊原基分化期; 6月下旬为雌蕊原基分化期。该研究明确了绵枣儿在哈尔滨地区的年生长节律和花芽分化各阶段的解剖学特性,为园林应用和新品种的选育提供了一定的科学依据。     

Morphological,anatomical, physiological,and cytological studies in diploid and tetraploid plants of Plantago psyllium

Plant Cell, Tissue and Organ Culture (PCTOC) - Plantago psylliumis is under development as the source of mucilage, but has not been entirely domesticated. Since mucilage content is low and variable...     

Morphological features,development and reproduction of Melittobia acasta on Bombus terrestris

Morphological features, development and reproduction behavior of the parasite Melittobia acasta (Walker) were studied when reared on the pupae of the bumblebee Bombus terrestris L. in the laboratory under 23°C, 50% relative humidity and 12 h light : 12 h dark conditions. The parasites laid transparent white and elongated eggs. Newly hatched larval size and shape were very similar to eggs but they were identified by their body segments. Larvae increased their body size through moulting and transformed into a vermiform shape. Male pupae were shiny brown with dots. The female pupae were distinguished by their black shiny color, shorter size and the presence of compound eyes. Adult male pupae were dark brown and dwarf‐winged, whereas female pupae were macropterous and brachypterous. Reproduction took place by fertilization and also parthenogenetically. Mean fecundity within 5 days by mated (47.9 ± 30.5 female^?1) and virgin (7.4 ± 6.8 female^?1) females were statistically different. Mated females laid fertilized eggs that produced adult males or females, whereas virgin females laid unfertilized eggs that produced males. Development durations of the virgin female originated eggs, larvae, pupae and adults were statistically identical with those of mated females. The parasites were female‐biased and foundress number did not affect offspring sex ratio. This study shows that both mated and virgin females of M. acasta can produce many offspring on B. terrestris pupae within a short period, indicating that they are dangerous parasites of the bumblebee in a mass rearing system.     

Morphological and anatomical changes of Melaleuca cajuputi under submergence

Melaleuca cajuputi is a woody plant of the Myrtaceae which is a dominant species in tropical peat swamps in southern Thailand, where the groundwater level fluctuates greatly. Although the current year seedlings are likely submerged, their adaptive responses have never been studied. The objective of the present study was to examine their responses to submergence, and especially their morphological and anatomical changes. Not only did the seedlings of M. cajuputi survive submergence for 56 days, but they could also increase their dry weight, shoot length, and leaf number during submergence. These growth responses to submergence indicate that the seedlings of M. cajuputi could make photosynthetic production under water. The leaves that developed under water were heterophyllous “aquatic leaves” that appear to represent adaptations to improve the uptake of gases from the water. Intercellular spaces in the stems and leaves were more strongly developed in the submerged seedlings than in non-submerged seedlings with the shoot and leaves in the air. The intercellular spaces appear to be schizogenous aerenchyma that facilitates gas exchange. The growth responses and anatomical responses in stems and leaves to submergence, which were found in M. cajuputi, are commonly known in herbaceous plants with amphibious characteristics, but had not been reported in woody plants. And our results suggest that M. cajuputi adapts to submergence similarly to other amphibious plants, thereby ensuring continuing biomass production.     

Morphological and anatomical relationships of loblolly pine fine roots

 Suberized or brown roots have been traditionally considered secondary or woody tissues. The validity of using morphological features such as color to infer root anatomy for southern pines is questionable and unproven. The objectives of this study were (i) to establish relationships between root color, diameter, and developmental stage (i.e., primary or secondary tissues) for loblolly pine, (ii) to determine the percentages of primary and secondary brown roots by diameter class, and (iii) to use these percentages to make first order estimates of the amount of brown root length and surface area that is in the primary and secondary developmental stages for sampled roots of a semi-mature loblolly pine stand. ”Unsectioned” roots were collected by coring to a 25-cm depth 3 times a year and measuring roots for length and surface area by diameter class. ”Sectioned” roots were sampled from a one-time core and from periodic grab samples. These roots were sectioned and characterized by their color, diameter and developmental stage. Diameters of sectioned roots (n=353) ranged from 0.21 to 8.24 mm. White and orange roots ranged from 0.23 to 2.50 mm, while brown roots spanned the range. White roots were developmentally primary, whereas orange/brown roots were either primary (from 0.21 to 2.50 mm), secondary (from 0.33 to 8.24 mm), or in transition (from 0.27 to 0.76). Total live root length of the sampled stands was estimated to be composed of 38% primary tissue, 58% secondary tissue, and 4% transition tissue. Lastly, neither root color nor diameter was a reliable predictor of developmental stage unless roots were white (primary), or orange/brown and >2.5 mm in diameter (secondary). Received: 30 June 1997 / Accepted: 28 January 1998     

Morphological and anatomical differentiation ofVellozia hirsuta populations (Velloziaceae)

The morphological and leaf anatomical differentiation ofVellozia hirsuta is analysed and classified into several types (A1, A2, A4, B3, B5, C3). The species has a relatively wide distribution in the campos rupestres of Minas Gerais in Brazil. The variation of the isolated populations on different mountain ranges is complex, does not follow a clear geographical pattern, and defies taxonomic classification.     

Morphological and anatomical features of Cuscuta pedicellata and C. campestris

Observations on morphological and anatomical features of Cuscuta pedicellata and, to a lesser extent, C. campestris have been made at different stages of their life-cycles. The seedling is filiform with a bulbous radicular end which collapses early. The simple shoot apex is green and photosentitive. Initial "nutation" is followed by "creeping" over the substrate. Host plants less than about three weeks old seem not to be attacked by Cuscuta seedlings. When haustorial contact is established the shoot apex differentiates into buds and scale leaves. The chlorophyll disappears and stomata, which are lacking in the seedling, develop. The apical growth rate increases strongly by frequent cell division and - elongation. This is reflected anatomically by the formation of "cell families" in rows. Weakening and flowering of the host plants are followed by flowering of the parasite. Greening of stem segments of Cuscuta occurs during formation of haustoria and after death of the host. Stem anatomy is characterized by a tripartite cortex in which the middle layer consists of thin-walled angular cells. Characteristic are also the voluminuous intercellular spaces, the cortical and perivascular laticifers, and the central position of the small vascular bundles. Observations on self-parasitism were made. The epidermis of the haustorial cushion elongates and the cytoplasm is mainly positioned towards the host. Pseudo-intercellular spaces are formed between the epidermal cells. The haustorium connects the phloem of the two plants, but vascular elements of any kind have not been observed.     

伞形科东当归的果实形态和解剖结构

对伞形科(Apiaceae)当归属(Angelica L.)东当归〔A.acutiloba(Sieb.et Zucc.)Kitag.〕的分生果形态特征和解剖结构进行了全面观察。该种分生果的外观呈倒椭圆状长卵形,有三角状萼齿,果棱、棱槽和腹面表面均有黄白色斑点。果实横切面解剖结构具有以下特征:外果皮终止于果棱顶端的腹面处,合生面宽阔,外果皮和中果皮细胞中有大量淡黄色晶体,油管在棱槽和合生面处连续分布等。东当归的这些果实形态及解剖结构明显不同于当归属的其他种类,其分类地位有待重新探讨。     

Morphological studies on neuroglia

Immunohistochemical studies with the use of the peroxidase-antiperoxidase (PAP) method revealed that "amoeboid microglial cells", in the brains of neonatal rats and "brain macrophages" in lesioned brains of adult rats react positively to an antiserum raised against macrophages. In brains of neonatal rats, "amoeboid microglial cells" stained by means of the PAP-method were observed in the corpus callosum, internal capsule, dorso-lateral region of the thalamus, subventricular zone of the lateral ventricle, and the subependymal layer of the ventricular system. These cellular elements were not detected in brains of rats aged 21 days or older. Resting microglial cells displaying a typical ramified structure were not specifically stained. Cells reacting positively to the macrophage antiserum appeared (i) in the cerebral cortex of adult rats following placement of a stab wound, or (ii) in the hippocampal formation after kainic acid-induced lesions; in the damaged areas immunoreactive cells exhibited the typical features of "brain macrophages". "Brain macrophages" and "amoeboid microglial cells" are considered to belong to the class of exudate macrophages derived from blood monocytes. Thus, elements of hematogenous origin do exist in the intact brain parenchyma of neonatal rats and in lesioned brains of adult rats. The relationship between brain macrophages and resting microglial cells is discussed.     

Morphological studies on neuroglia

Summary Autoradiographic studies showed that in the rat hippocampus microglia-like reactive cells (MRC) and astrocytes are capable of proliferation in response to kainic acid (KA)-induced lesions. A marked increase in the number of labeled MRC was observed during the first four days after the induction of the KA-lesion. A proliferative response of astrocytes occurred at two days after the KA-lesion. After the induction of a KA-lesion brain macrophages and oligodendrocytes were only slightly labeled with ³H-thymidine. It appears likely that MRC is the main cellular element responding to this type of lesion.This work was supported by a grant (No. 437002) from the Ministry of Education, Science and Culture, Japan