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1.
This work reports isolation of an unusual lignan with a bicyclic [2.2.2] octene skeleton, named rufescenolide (1), from stems of Cordia rufescens, along with β-sitosterol, stigmasterol, syringaldehyde, 3-β-O-d-glucopyranosyl-sitosterol, methyl caffeate, 4-methoxy-protocatechuic acid and methyl rosmarinate. Structural characterizations employed IR spectroscopic, ESIHRMS and mono and dimensional NMR spectroscopy.  相似文献   

2.
Getulio Agostini 《Brittonia》1973,25(2):174-176
Cordia thaisiana is described as new from the state of Zulia, Venezuela. It can be distinguished from other species in the section by the inconspicuously nerved calyx, the flower disk fused with the ovary, and by the glabrous branches and leaf blades. A key is provided for the species ofCordia sect.Gerascanthus growing in northern South America.  相似文献   

3.
The genus Cordia (Boraginaceae) is made up of a great many species widely distributed in tropical and subtropical regions of the world. The leaves ofCordia myxa, as also those of many other species of the same genus, have been utilized in the traditional medicine of many countries for the treatment of a variety of diseases. Observed by light microscope and by scanning electron microscope the histological characteristics of the leaf ofCordia francisci, C. martinicensis, C. serratifolia andC. ulmifolia, species grown in Sicily, compared also with those of the leaves ofC. myxa originating from Africa, are described in detail. It has been possible to reveal some morphological elements that allow leaf identification and the differentiation of the drugs examined.  相似文献   

4.
Thaumatovalva gen. n. is described and illustrated from the Afrotropical region. As currently defined the genus includes four species: T. deprinsorum sp. n. from the Democratic Republic of Congo; T. albolineana sp. n. (type species) from the Democratic Republic of Congo; T. spinai (Razowski & Trematerra), comb. n., from Ethiopia and Nigeria; and T. limbata (Diakonoff), comb. n., from the Seychelles and Kenya. Thaumatovalva limbata has been reared from the fruit of Cordia somaliensis Baker and C. monoica Roxb. (Boraginaceae) in Kenya. Although structures of the male and female genitalia are extremely similar among three of the four species, male secondary scales on the under surface of the hindwing easily distinguish them.  相似文献   

5.
We describe four new species of Cordia (Cordiaceae) from Brazil: Cordia fusca, C. glabrifolia, C. restingae, and C. tarodae. These are illustrated, and data on habitat, phenology, and distribution are provided.  相似文献   

6.
7.
A new species of Puccinia with diorchidioid teliospores is described from Urochloa decumbens (Poaceae) in Panama. It differs from the other known species of Puccinia with diorchidioid teliospores by uredinia with paraphyses and urediniospores with 3–4 scattered germ pores. Twenty-one known species of rust fungi are cited for Panama for the first time. Alveolaria cordiae is a poorly known species which is reported, described and illustrated in detail for the first time on Cordia spinescens in Panama.  相似文献   

8.

Background and Aims

The close relationship between distylic Cordia leucocephala and the bee Ceblurgus longipalpis, both endemic to the Caatinga, north-east Brazil, was investigated, emphasizing reproductive dependence, morphological adaptations of the partners, and pollen flow.

Methods

In the municipality of Pedra, in the Caatinga of Pernambuco, the breeding system and reproductive success of C. leucocephala, its interaction with flower visitors and inter- and intramorph pollen flow were determined.

Key Results

The bee Ceblurgus longipalpis, the unique flower visitor and effective pollinator of self-incompatible Cordia leucocephala, presents morphological features adapted to exploit hidden pollen and nectar in the long and narrow corolla tubes. Pollen of low-level anthers is collected with hairs on prolonged mouthparts and pollen of high-level anthers with clypeus, mandibles, and labrum, showing pollen removal from both levels with the same effectiveness. In both morphs, this results in similar legitimate, i.e. intermorph cross-pollen flow. Illegitimate pollen flow to stigmas of pin flowers, however, was much higher than to stigmas of thrum flowers. Moreover, more illegitimate pollen was transported to stigmas of pin and less to those of thrum flowers when compared with legitimate pollen flow.

Conclusions

The study reveals a one-to-one reproductive inter-dependence between both partners. Data indicate that this relationship between bee species and plant species is one of the rare cases of monolecty among bees. Monotypic Ceblurgus longipalpis, the only rophitine species of Brazil, evolved prolonged mouthparts rare among short-tongued bees that enable them to access pollen from flowers with short-level anthers hidden for bees of other species, and nectar at the base of the flower tube.  相似文献   

9.
F. J. Simmonds 《BioControl》1980,25(4):363-364
Metrogaleruca obscura DeGeer (=Schematiza oordiae Barber) (Galerucidae) from Trinidad andEurytoma attiva Burks (Eurytomidae) from Mauritius, introduced into Malaysia in 1977 for the control of the introduced neotropical weedCordia curassavica (Jacq.) R. & S. are established. Despite attack by native parasites and predators a rapid build up accompanied by impressive defoliation and seed destruction suggested that biological control will be achieved.  相似文献   

10.
The influence of vesicular-arbuscular mycorrhizae on the growth of seedlings of Caesalpinia eriostachys, Cordia alliodora, Ipomoea wolcottiana and Pithecellobium mangense was investigated in a greenhouse experiment conducted at the Biological Station of Chamela on the Pacific coast of Mexico. Dry biomass production, relative growth rate, root/shoot ratio and mycorrhizal dependency were quantified for 75-day-old seedlings. With the exception of the pioneer species I. wolcottiana, mycorrhizal infection resulted in increases in biomass production, relative growth rate and leaf area. The root/shoot ratios attained for the species, however, did not show a consistent trend with infection. Nevertheless, all species had root/shoot ratios below 1 with infection and only one, Cordia alliodora, had a ratio greater than 1 without infection. The two late successional species from the mature part of the forest, Caesalpinia eriostachys and P. mangense, showed a larger mycorrhizal dependency than the two associated with disturbed environments.  相似文献   

11.
Our study examines how the mutualism between Atta colombica leaf-cutting ants and their cultivated fungus is influenced by the presence of diverse foliar endophytic fungi (endophytes) at high densities in tropical leaf tissues. We conducted laboratory choice trials in which ant colonies chose between Cordia alliodora seedlings with high (Ehigh) or low (Elow) densities of endophytes. The Ehigh seedlings contained 5.5 times higher endophyte content and a greater diversity of fungal morphospecies than the Elow treatment, and endophyte content was not correlated with leaf toughness or thickness. Leaf-cutting ants cut over 2.5 times the leaf area from Elow relative to Ehigh seedlings and had a tendency to recruit more ants to Elow plants. Our findings suggest that leaf-cutting ants may incur costs from cutting and processing leaves with high endophyte loads, which could impact Neotropical forests by causing variable damage rates within plant communities.  相似文献   

12.
Forest species can have their seeds damaged by granivorous insects, especially by those in their larval stage. In this context, this study aims to report the occurrence of Amblycerus species in Cordia trichotoma seeds, to describe their main damage to seeds and effects on germination, as well as their associated hymenopteran parasitoids. Therefore, seven trees were selected in the municipality of Taquaruçu do Sul, RS, Brazil. Fruits were collected weekly from the medium third of the tree crown, from the beginning of their formation until total dehiscence. To examine the damage caused by granivorous insects within the fruits, 15 fruits from each tree were sectioned with a scalpel. Furthermore, 10 fruits from each tree were stored individually in clear plates to verify the occurrence and identification of granivorous insect species. Evidence of the damage caused to seeds was verified through the germination test by comparing preserved and damaged seeds, with four repetitions of 25 seeds each. The species Amblycerus longesuturalis and Amblycerus profaupar (Chrysomelidae: Bruchinae) were found associated with fruits of C. trichotoma. Female insects predominantly laid eggs on the superior part between the marcescent calyx and the fruit, and larvae perforated the fruit tegument to start consuming seed embryos and reserves. Bruquine larvae are parasitized by Hymenoptera of Bracon, Mirax, Omeganastatus and Triapsis genera. In conclusion, the germination of C. trichotoma seeds is significantly affected by emergence orifices caused by granivorous species.  相似文献   

13.
The neutral polysaccharide isolated from the fruits of Cordia dichotoma was separated into two fractions, I and II, by gel filtration using Sephadex G-100. The major fraction, II, was found to contain d-glucose and l-arabinose in the molar ratio of 21:4. The results of complete hydrolysis with acid, permethylation studies, periodate oxidation, and Smith degradation suggested it to be an arabinoglucan, and the backbone of the polysaccharide to be composed of (1→6)-linked d-gluco-pyranosyl and (1→2)-linked l-arabinofuranosyl residues. The average degree of polymerization, determined through end-group analysis, was found to be ~144.  相似文献   

14.
Exploring the factors governing the maintenance and breakdown of cooperation between mutualists is an intriguing and enduring problem for evolutionary ecology, and symbioses between ants and plants can provide useful experimental models for such studies. Hundreds of tropical plant species have evolved structures to house and feed ants, and these ant–plant symbioses have long been considered classic examples of mutualism. Here, we report that the primary ant symbiont, Allomerus cf. demerarae, of the most abundant ant-plant found in south-east Peru, Cordia nodosa Lam., castrates its host plant. Allomerus workers protect new leaves and their associated domatia from herbivory, but destroy flowers, reducing fruit production to zero in most host plants. Castrated plants occupied by Allomerus provide more domatia for their associated ants than plants occupied by three species of Azteca ants that do not castrate their hosts. Allomerus colonies in larger plants have higher fecundity. As a consequence, Allomerus appears to benefit from its castration behaviour, to the detriment of C. nodosa. The C. nodosa–ant system exhibits none of the retaliatory or filtering mechanisms shown to stabilize cheating in other cooperative systems, and appears to persist because some of the plants, albeit a small minority, are inhabited by the three species of truly mutualistic Azteca ants.  相似文献   

15.
In this study, the leaves extract of Cordia myxa, has been used for the first time to synthesize zinc oxide (ZnO) hierarchical microstructures. The solution combustion method was employed as a self-sustaining reaction between zinc nitrate and the leaves extract. The surface properties of leaves mediated ZnO microstructures were determined by UV–Visible spectral analysis, Fourier transform infrared (FT-IR), Cold field emission-scanning electron microscopy (CFE-SEM), Energy dispersive X-ray (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). In addition, the effect of the leaves extract concentration on ZnO structures, size and surface properties was also studied. ZnO structures synthesized employing C. myxa were found to be hexagonal, triangular and round in shape which was determined using CFE-SEM. X-ray diffraction (XRD) analysis confirmed the crystalline nature of compounds. Furthermore, C. myxa mediated ZnO microstructures shows good bactericidal activity against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria.  相似文献   

16.
We recorded stingless bee colony abundance and nesting habits in three sites with different anthropogenic activities in the Soconusco region of Chiapas, Mexico: (1) agroforestry (7 hacacao crop), (2) grassland (12?ha), and (3) urban area (3?ha). A total of 67 nests were found, representing five stingless bee species, Tetragonisca angustula angustula (Lepeletier), Trigona fulviventris (Guérin), Scaptotrigona mexicana (Guérin), Scaptotrigona pectoralis (Dalla Torre), and Oxytrigona mediorufa (Cockerell). The most abundant stingless bee in each site was T. angustula angustula (>50%). The primary tree species used by the bees were Ficus spp. (Moraceae, 37.8%) and Cordia alliodora (Boraginaceae, 13.5%). The nest entrance height of T. angustula angustula (96?±?19?cm) was different than the other species, and this bee was the only one that used all different nesting sites. Volatiles analyzed by gas chromatography from pollen collected by the stingless bees differed between bee species, but were highly similar in respect to the fragrances of the pollen collected by the same species at any site. Our data indicate that T. angustula angustula experienced low heterospecific and high intraspecific foraging overlap especially in the urban site. We observed cluster spatial distribution in grassland and in agroforestry sites. In the urban site, T. angustula angustula presented random distribution tended to disperse. Trigona fulviventris was the only overdispersed and solitary species.  相似文献   

17.
Abiotic environmental variables strongly affect the outcomes of species interactions. For example, mutualistic interactions between species are often stronger when resources are limited. The effect might be indirect: water stress on plants can lead to carbon stress, which could alter carbon-mediated plant mutualisms. In mutualistic ant–plant symbioses, plants host ant colonies that defend them against herbivores. Here we show that the partners'' investments in a widespread ant–plant symbiosis increase with water stress across 26 sites along a Mesoamerican precipitation gradient. At lower precipitation levels, Cordia alliodora trees invest more carbon in Azteca ants via phloem-feeding scale insects that provide the ants with sugars, and the ants provide better defense of the carbon-producing leaves. Under water stress, the trees have smaller carbon pools. A model of the carbon trade-offs for the mutualistic partners shows that the observed strategies can arise from the carbon costs of rare but extreme events of herbivory in the rainy season. Thus, water limitation, together with the risk of herbivory, increases the strength of a carbon-based mutualism.  相似文献   

18.
The pollen of 40 species of Cordia L. was studied by light microscopy and scanning and transmission electron microscopy. Three major types were found, 3-porate with a reticulate sexine, 3-colpate to 3-colporoidate with a striatoreticulate sexine, and 3-colpate to 3-colporate with a spinulose sexine. These pollen types are correlated with significant differences in the inflorescence, flower, and fruit structures found in the sporophyte. The following revisions are suggested and discussed: that Cordia sect. Varronia P. Br. be elevated to generic status; that Cordia sebestena L. and a few close allies be treated as generically distinct; and that Cordia myxa L. be conserved as the lectotype for the genus, thus continuing a wide application of the epithet Cordia.  相似文献   

19.
We provide an estimate of genetic differentiation within and among 11 populations of Cordia alliodora, an economically important timber tree Cordia alliodora is a widespread species that is distributed throughout Central and South America. Our survey of isozyme variation was conducted on material gathered for international provenance trials over approximately 1,000 km in Central America. Results from provenance trials indicate that there are significant differences between Atlantic and Pacific coast provenances for quantitative characters. Genetic data support some of these findings. Populations of C. alliodora show significant differences in allele frequency at various loci. Significant differences in multilocus allele frequencies occur at 13 of the 55 possible combinations. Eight of these 13 populations are situated on opposite coasts. This physical separation corresponds well with the results of provenance trials that indicate differentiation among the Atlantic and Pacific populations in quantitative morphological traits. We also found a significant negative correlation between levels of heterozygosity and the amount of rainfall, indicating that populations from the drier zone are genetically more heterogenous than populations from the wet zone. Our study indicates that in situ and ex situ conservation should accord high priority to the dry zone populations; furthermore, conservation of this widespread species would require preservation of multiple populations.  相似文献   

20.
Cordia verbenacea DC (Boraginaceae) is a Brazilian coastal shrub species extensively utilized in the folk medicine and also by the pharmaceutical industry. Despite its enormous economic and pharmacological potential, little is known about its reproductive biology, genetic structure and genetic diversity of natural populations. Due to the rapid degradation of its natural habitat, this knowledge became imperative. We developed a set of eight highly polymorphic microsatellite markers for the study of genetic structure and diversity of C. verbenacea natural populations and germplasm collections. Six of them revealed a multibanded pattern typical of polyploid species. The total number of bands per locus ranged from 2 to 12 and the number of bands per locus per individual ranged from 1 to 8. The primer pairs presented here will be used to generate information to guide conservation programs and rational exploitation of C. verbenacea.  相似文献   

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