旌节花科及其相关类群花粉形态的研究

对旌节花科及其相关类群五桠果科、猕猴桃科、水东哥科、金莲木科、省沽油科和山茶科等7科19属37种花粉进行了光镜（LM）和扫描电镜（SEM）的观察和比较。其中有些种类是第一次观察和报道。研究表明,上述各科花粉多为近球形至球形,少数近扁球形或近长球形。极面观三裂圆形或近三裂圆形。直径20－30（－35μm）,但厚皮香亚科和省沽油科银鹊树属Tapiscia的花科特别小,仅12.5-20μm。3孔沟,罕有3沟或4孔沟。外萌发孔（沟）相对地较长而宽,内孔多数较发达。花粉外壁纹饰变化大,从模糊而粗糙的细突起到皱波状纹饰,细孔状纹饰,蜂巢状－穴状纹饰,穴－网状纹饰,网状纹饰和颗粒状纹饰等。从形状、大小、萌发孔类型和外壁纹饰的比较看,虽然上述各科花粉均在不同程度上具有一定的相似性,但其中以旌节花科、省沽油科和山茶科中厚皮香科的花粉具有更多的相似性,尤其表现在外壁纹饰特征上。就孢粉学而言,也许旌节花科与省沽油科和山茶科中的厚皮香亚科的关系相对地较为密切。不过,其孢粉学特征所表现出的亲缘关系似乎不如在分子生物学中所表现出的明显。     

Ellagitannins of the casuarinaceae,stachyuraceae and myrtaceae

Eight ellagitannins and related polyphenols, found in Casuarina stricta and Stachyurus praecox, were detected in the leaf of Psidium species. Five of them and a new polyphenol, named isostrictinin, were isolated from Psidium guajava. Most of these compounds were detected in several species of Myrtaceae, and 2, 3-hexahydroxydiphenoylglucose and 4, 6-hexahydroxydiphenoylglucose were found in some.     

Floral anatomy of the Styracaceae, including observations on intra-ovarian trichomes

DICKISON, W. C., 1993. Floral anatomy of the Styracaceae, including observations on intra-ovarian trichomes All eleven genera of the Styracaceae were examined with respect to floral morphology and anatomy. Floral structure and vascularization are described in detail. Flowers of the family exhibit different degrees and patterns of specialization. All Styracaceae show some degree of basal non-divergence of perianth members, forming a hypanthium that is adnate to the ovary wall to a lesser or greater extent. The extent of reduction and amplification in the number of sepals, petals, stamens, and carpels varies widely among genera, and generally the non-divergence, decrease, or increase in parts is not equally pronounced in the different whorls of the same flower. Genera cannot be readily aligned in an intergrading sequence of morphological advancement. Stamen form and anatomy is variable. A fibrous endothecium ranges from well-developed to weakly formed or absent. A nearly uniform feature of the styracaceous gynoecium is the presence of incompletely septate ovaries. The major points of variation in the floral vascular system relate to the number, mode of origin, and degree of independence of sepallary traces; degree of independence of the androecial vasculature; the level at which the common petal and petalad-stamen or sepal and sepalad-stamen bundles separate to their component parts; organization of the ventral ovarian supply; and the occurrence of ventral bundles in the style. Floral vascularization provides evidence that the family was derived from an obdiplostemonous ancestor. A unitegmic ovule is predominant in the family and starch is present in the megagametophyte of some taxa. An unusual feature of the flowers of the Styracaceae is the occurrence of stellate and lignified intra-ovarian trichomes. Numerous similarities in floral morphology and anatomy between Styracaceae and Ericales are pointed out.     

Flavonoid chemistry of the generic segregates Ascyrum and Crookea of Hypericum

Leaf flavonoids were isolated and characterized from the seven taxa of Hypericum, formerly segregated as Ascyrum and Crookea. These included flavonol 3-glycosides based on quercetin and kaempferol and flavone-O-glycosides and C-glycosides based on apigenin and luteolin. The flavonoid data do not indicate that the taxe of Ascyrum and Crookea form a single coherent group and hence support their merger with Hypericum.     

旌节花科与省沽油科花粉形态的研究

对旌节花科和省沽油科 4属 13种花粉进行了光镜和扫描电镜的观察 ,其中有些种是第一次观察或报道。这两个科的花粉为近球形到球形 ,3孔沟 (省沽油科银鹊树属TapisciaOliv花粉除外 ,为 3沟 )。它们的花粉大小和外壁纹饰有一定差异。旌节花科花粉相对较小 ,一般为 18～ 2 8 2× 17 5～ 2 6 5 μm ,外壁表面为穴状纹饰。省沽油科花粉较大 ,为 2 8～ 4 0× 2 8 5～4 0 5 μm (银鹊树属花粉只有 13 5～ 17 9× 12 5～ 18μm) ,外壁表面为细网状纹饰。这两个科的花粉特征在某种程度上具有一定的相似性 ,故就孢粉学而言它们具有颇为密切的关系     

Phenolic compounds from the roots of Ochna schweinfurthiana and their antioxidant and antiplasmodial activities

An investigation of compounds extracted from Ochna schweinfurthiana roots with ethyl acetate led to the isolation of three new compounds 4⿴-methoxylophirone A (1), 4,4⿲,4⿴⿿trimethoxylophirone A (2) and (4E;7Z)-3,8-dicarboxy-1-(O-β-d-glucopyranosyl-(1 ⿿ 6)-O-β-d-glucopyranosyl-2,9-dihydroxyhexeicosa-4,7-diene (3). Six known compounds were also identified, including Calodenone (4), Calodenine B (5), Lophirone A (6), Gerontoisoflavone A(7), 16α,17-dihydroxy-ent-kauran-19-oic acid (8) and 3β-O-d-glucopyranosyl-β-sitosterol (9). This report describes the first time that compounds 4-8 have been isolated from this plant, while 8 has never been identified in the genus Ochna. Some of the isolated compounds were evaluated for their antiplasmodial activity against the chloroquine-sensitive Plasmodium falciparum strain 3D7 and antioxidant activity using DPPH radical scavenging and Ferric reducing-antioxidant power (FRAP) assays. Compound 5 exhibited prominent radical scavenging and FRAP activities, while 7 had weak activity. Compound 1 showed good in vitro anti-plasmodial activity. The structures of the isolated compounds were elucidated by spectroscopic methods and comparisons with prior data in the literature.     

Tetrahydrodiospyrin: a reduced binaphthoquinone from the bark of Diospyros montana

A new reduced dimeric 7-methyljuglone isolated from the fresh bark of D. montana is shown to be 3′,7-dimethyl-5′,6′,7′,8′-tetrahydro-1′,5,5′-trihydroxy [2,2′-binaphthalene]-1,4,8′-trione.     

Isolation and characterization of microsatellite loci from the endangered highlands scrub hypericum (Hypericum cumulicola)

We report the isolation of 19 primer pairs for amplification of polymorphic microsatellite loci for Hypericum cumulicola. These markers were evaluated in 24 individuals from one population; two to four alleles were detected per locus, and observed heterozygosity ranged from 0 to 0.5. Two loci demonstrated significant heterozygote deficiencies, possibly due to null alleles, and significant linkage disequilibrium was found between six pairs of loci. The remaining microsatellite loci will help determine if genetic differentiation is responsible for life‐history differences between natural and anthropogenically disturbed populations of H. cumulicola.     

Studies in Garcinia, dioecious tropical forest trees: the phenology, pollination biology and fertilization of G. hombroniana Pierre

RICHARDS, A. J., 1990. Studies in Garcinia , dioecious tropical forest trees: the phenology, pollination biology and fertilization of G. hombroniana Pierre . Garcinia hombroniana is a facultative agamosperm which is pollinated by Trigona bees. Nectar is restricted to the large discoid stigma (or pistillode in male flowers), which also captures and hydrates pollen. The 'wet' stigma and binucleate pollen suggest that Garcinia arose from hermaphrodite plants with a gametophytic self-incompatibility system.
On stigmas, nectar is secreted early on three or four successive days. On male pistillodes, nectar is secreted when anthers dehisce, on the second morning after anthesis. Pollen is most viable when freshly collected, but some viability remains four days after collection. Pollen germinates within 24 h of hydration. Similar results to pollinations are obtained by germinating pollen in 1 % sucrose.
Garcinia hombroniana flowers principally from January to June. Cultivated females are considered as 'big bang' strategists. Male flowers are considered as 'steady state' strategists.     

Triterpenoids and steroids of some Sapotaceae and their chemotaxonomic significance

Extraction of the bark and timber of four Madhuca and five Palaquium species has yielded β-amyrin, β-amyrin acetate, β-amyrin cinnamate,     

A synopsis of the family Lissocarpaceae

A species erroneously described as aDiospyros is here transferred toLissocarpa, asL. tetramera (Rusby) P. E. Berry. This gives a total of five species currently recognized in Lissocarpaceae. A key to the species and a discussion of the individual taxa are presented.     

Isolation and identification of a citrato-complex of nickel from nickel-accumulating plants

An organometallic complex of nickel has been isolated from nickel-accumulating plants of New Caledonia and has been identified by a combination of infrared spectroscopy, high-voltage paper electrophoresis, gas-liquid chromatography and mass spectrometry. Most of the nickel in Sebertia acuminata, Homalium francii, Homalium guillainii, Homalium kanaliense, Hybanthus austrocaledonicus and Hybanthus caledonicus is found as a negatively-charged citratonickelate (II) complex with Ni(H₂O)₆²⁺ as the major cationic constituent.     

Carotenoid changes in the peel of ripening persimmon (Diospyros kaki) cv Triumph

The changes of the carotenoid pigments in the peel of ripening persimmon (Diospyros kaki) cv Triumph were followed for an entire season. During ripening, the total carotenoid decreased until colour break, then increased gradually and drastically at the last ripening stages. The chloroplast carotenoid pattern of the unripe fruit changed into a chromoplast pattern in which cryptoxanthin was the predominant pigment, reaching a level between 40 and 50% of the total carotenoids. It accumulated continuously at a rate of approximately 10% at each 2 week interval, its percentage being characteristic for each ripening stage. Other major pigments at levels of approximately 10% of the total carotenoids were zeaxanthin, antheraxanthin and violaxanthin. In the fully ripe fruit, ripened both on and off the tree, lycopene which was not present before was found as the second major pigment. This unusual pattern change is discussed.     

Morphology and systematics of the Scytopetalaceae

The present study is based on a re-investigation of the vegetative and reproductive structures of the West African family Scytopetalaceae. Special emphasis is paid to inflorescence morphology and seed anatomy. The inflorescences of all genera of Scytopetalaceae can be interpreted as derived from panicles through reductions and structural changes. Thyrsoids prevail, but panicles, botryoids and racemes occur as well. Within the family cauliflory appears as the derived condition. Seed coat structure is extremely simplified and very stable in the Scytopetalaceae. The horny endosperm contains amyloid as the main storage compound. The presence of two obviously different forms of ruminate endosperm indicates that rumination arose twice within the family. The neotropical genus Asteranthos (Lecythidaceae) agrees in almost all relevant characters with the Scytopetalaceae. Therefore the proposed inclusion of Asteranthos in the latter family is fully confirmed. Scytopetalaceae, Lecythidaceae, Foetidiaceae and Napoleonaeaceae apparently form a natural alliance. Two new subfamilies (Scytopetaloideae, comprising Scytopetalum, Oubanguia , and Asteranthos; Rhaptopetaloideae comprising Rhaptopetalum, Pierrina and Brazzeia ) are proposed and fully described.     

Germination performance of congeneric Styrax species from the Cerrado sensu lato areas and their distribution pattern in different physiognomies

When studying congeneric species, it is of reasonable importance to understand different ecophysiological performances which might determine the distribution of species in habitats with different natural resources. Styrax ferrugineus is exclusive and well adapted to the Brazilian Cerrado sensu stricto (s. str.); S. camporum is widely distributed in the Cerrado sensu lato (s. l.) areas, with young trees being observed at the edge of cerradão and other vegetation fragments; and S. pohlii occurs in permanently waterlogged soils of the Cerrado region, such as those of riparian forests. We tested the hypothesis that the higher the soil water content in the physiognomic gradient of the vegetation, the higher is the germination success of S. pohlii, but the lower is the germination success of S. ferrugineus. We also discuss whether gap conditions inside a cerradão fragment imply a high germination rates of seeds of S. camporum. Seeds from each of the three species were buried within nylon bags containing soil from the respective sites. Burial occurred in a Cerrado s. str., in understory and gap conditions of a cerradão, and in the understory of a riparian forest fragment, and lasted for 60, 120, 180 and 240 days, respectively, after the fruit dispersal time of each of the three species. After 60 days, a relationship was found showing that the percentage of germinated seeds diminished, and the percentage of damaged seeds increased as soil water content increased (Cerrado s. str. < cerradão gap < cerradão understory ? riparian forest). S. camporum still showed viable seeds 60 days after burial (DAB), and germinated seeds 120 DAB, indicating that it needed a longer time to germinate, which might be associated to its thicker seed coat, in relation to the other two species. The germination performance of each of the three species was the same in the gap and understory conditions of the cerradão. The higher concentration of adult S. camporum plants at the edge of vegetation fragments is not related to a particular high germination performance and seedling establishment.