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The volatile composition of needles from three F1 hard pine hybrids produced by the controlled hybridization and their parental species were researched with gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) in order to explore the utility of terpenes in hybrid identification (their differentiation from the parental species) as well as confirmation of hybridity. The analysed hybrids were: 1. Pinus nigra J. F. Arnold × Pinus sylvestris L. (= nisy), 2. P. nigra × Pinus densiflora Siebold et Zucc. (= nide) and 3. P. nigra × Pinus thunbergiana Franco (= nith). A total of 55 compounds were identified. All identified compounds were terpenes, except trans-2-hexenal.Three analysed F1 hybrids showed the same qualitative pattern of the needle volatile composition as their parental species. However, there were quantitative differences in several major terpenes. The volatile composition of the needles from the hybrids nisy were equally similar to both parents, the hybrids nide were more similar to the female parent (P. nigra), whereas the hybrids nith were more similar to the male parent (P. thunbergiana). According to the content of germacrene D, as the specific component of P. nigra (female parent of the three analysed F1 hybrids), all hybrids were intermediary in relation to the parental species. The content of Δ-3-carene (the specific component of P. sylvestris) in the hybrids nisy was also intermediary. The hybrids nide had a higher content of thunbergol (specific component of P. densiflora) than the other analysed hybrids. In view of the content of β-pinene, the specific component of P. thunbergiana, the hybrids nith were intermediary to the parental species and that content was considerably higher than in the other analysed hybrids. The intermediary quality of F1 hybrids for these specific components in relation to the parental species confirms their hybrid character.The needle volatile composition analysis as well as the previous morphometric analysis confirm the hybrid character of three F1 hybrids, whose female parent is P. nigra, and male parents are P. sylvestris, P. densiflora, i.e. P. thunbergiana.  相似文献   

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The genera Odontacolus Kieffer and Cyphacolus Priesner are among the most distinctive platygastroid wasps because of their laterally compressed metasomal horn; however, their generic status has remained unclear. We present a morphological phylogenetic analysis comprising all 38 Old World and four Neotropical Odontacolus species and 13 Cyphacolus species, which demonstrates that the latter is monophyletic but nested within a somewhat poorly resolved Odontacolus. Based on these results Cyphacolus syn. n. is placed as a junior synonym of Odontacolus which is here redefined. The taxonomy of Old World Odontacolus s.str. is revised; the previously known species Odontacolus longiceps Kieffer (Seychelles), Odontacolus markadicus Veenakumari (India), Odontacolus spinosus (Dodd) (Australia) and Odontacolus hackeri (Dodd) (Australia) are re-described, and 32 new species are described: Odontacolus africanus Valerio & Austin sp. n. (Congo, Guinea, Kenya, Madagascar, Mozambique, South Africa, Uganda, Zimbabwe), Odontacolus aldrovandii Valerio & Austin sp. n. (Nepal), Odontacolus anningae Valerio & Austin sp. n. (Cameroon), Odontacolus australiensis Valerio & Austin sp. n. (Australia), Odontacolus baeri Valerio & Austin sp. n. (Australia), Odontacolus berryae Valerio & Austin sp. n. (Australia, New Zealand, Norfolk Island), Odontacolus bosei Valerio & Austin sp. n. (India, Malaysia, Sri Lanka), Odontacolus cardaleae Valerio & Austin sp. n. (Australia), Odontacolus darwini Valerio & Austin sp. n. (Thailand), Odontacolus dayi Valerio & Austin sp. n. (Indonesia), Odontacolus gallowayi Valerio & Austin sp. n. (Australia), Odontacolus gentingensis Valerio & Austin sp. n. (Malaysia), Odontacolus guineensis Valerio & Austin sp. n. (Guinea), Odontacolus harveyi Valerio & Austin sp. n. (Australia), Odontacolus heratyi Valerio & Austin sp. n. (Fiji), Odontacolus heydoni Valerio & Austin sp. n. (Malaysia, Thailand), Odontacolus irwini Valerio & Austin sp. n. (Fiji), Odontacolus jacksonae Valerio & Austin sp. n. (Cameroon, Guinea, Madagascar), Odontacolus kiau Valerio & Austin sp. n. (Papua New Guinea), Odontacolus lamarcki Valerio & Austin sp. n. (Thailand), Odontacolus madagascarensis Valerio & Austin sp. n. (Madagascar), Odontacolus mayri Valerio & Austin sp. n. (Indonesia, Thailand), Odontacolus mot Valerio & Austin sp. n. (India), Odontacolus noyesi Valerio & Austin sp. n. (India, Indonesia), Odontacolus pintoi Valerio & Austin sp. n. (Australia, New Zealand, Norfolk Island), Odontacolus schlingeri Valerio & Austin sp. n. (Fiji), Odontacolus sharkeyi Valerio & Austin sp. n. (Thailand), Odontacolus veroae Valerio & Austin sp. n. (Fiji), Odontacolus wallacei Valerio & Austin sp. n. (Australia, Indonesia, Malawi, Papua New Guinea), Odontacolus whitfieldi Valerio & Austin sp. n. (China, India, Indonesia, Sulawesi, Malaysia, Thailand, Vietnam), Odontacolus zborowskii Valerio & Austin sp. n. (Australia), and Odontacolus zimi Valerio & Austin sp. n. (Madagascar). In addition, all species of Cyphacolus are here transferred to Odontacolus: Odontacolus asheri (Valerio, Masner & Austin) comb. n. (Sri Lanka), Odontacolus axfordi (Valerio, Masner & Austin) comb. n. (Australia), Odontacolus bhowaliensis (Mani & Mukerjee) comb. n. (India), Odontacolus bouceki (Austin & Iqbal) comb. n. (Australia), Odontacolus copelandi (Valerio, Masner & Austin) comb. n. (Kenya, Nigeria, Zimbabwe, Thailand), Odontacolus diazae (Valerio, Masner & Austin) comb. n. (Kenya), Odontacolus harteni (Valerio, Masner & Austin) comb. n. (Yemen, Ivory Coast, Paskistan), Odontacolus jenningsi (Valerio, Masner & Austin) comb. n. (Australia), Odontacolus leblanci (Valerio, Masner & Austin) comb. n. (Guinea), Odontacolus lucianae (Valerio, Masner & Austin) comb. n. (Ivory Coast, Madagascar, South Africa, Swaziland, Zimbabwe), Odontacolus normani (Valerio, Masner & Austin) comb. n. (India, United Arab Emirates), Odontacolus sallyae (Valerio, Masner & Austin) comb. n. (Australia), Odontacolus tessae (Valerio, Masner & Austin) comb. n. (Australia), Odontacolus tullyae (Valerio, Masner & Austin) comb. n. (Australia), Odontacolus veniprivus (Priesner) comb. n. (Egypt), and Odontacolus watshami (Valerio, Masner & Austin) comb. n. (Africa, Madagascar). Two species of Odontacolus are transferred to the genus Idris Förster: Idris longispinosus (Girault) comb. n. and Idris amoenus (Kononova) comb. n., and Odontacolus doddi Austin syn. n. is placed as a junior synonym of Odontacolus spinosus (Dodd). Odontacolus markadicus, previously only known from India, is here recorded from Brunei, Malaysia, Sri Lanka, Thailand and Vietnam. The relationships, distribution and biology of Odontacolus are discussed, and a key is provided to identify all species.  相似文献   

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In addition to a specific morphotype, each species has a unique ecologo-climatic niche and a geographical area. The study of ecologo-climatic and geographical divergence may significantly contribute to the comprehension of species genesis and amount. The aim of this work is to compare ecologo-climatic niches of Poa palustris L., P. nemoralis L., and populations combining the features of both species (assigned in this work to the hybridogenic complex of P. intricata Wien), as well as reveal their identity. As a result of these researches, the areas of the both species were verified. The ecologo-climatic niches were determined with the use of GIS technologies and on the basis of their coordinates. Then potential areas of species—the regions where climatic conditions are favorable for their growth—were determined on the basis of six independent bioclimatic variables. A comparison of the ecologo-climatic niches calculated by MaxEnt software has shown that their distinctions are statistically significant.  相似文献   

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The aim of the current study is to investigate whether homology models of G-Protein-Coupled Receptors (GPCRs) that are based on bovine rhodopsin are reliable enough to be used for virtual screening of chemical databases. Starting from the recently described 2.8 A-resolution X-ray structure of bovine rhodopsin, homology models of an "antagonist-bound" form of three human GPCRs (dopamine D3 receptor, muscarinic M1 receptor, vasopressin V1a receptor) were constructed. The homology models were used to screen three-dimensional databases using three different docking programs (Dock, FlexX, Gold) in combination with seven scoring functions (ChemScore, Dock, FlexX, Fresno, Gold, Pmf, Score). Rhodopsin-based homology models turned out to be suitable, indeed, for virtual screening since known antagonists seeded in the test databases could be distinguished from randomly chosen molecules. However, such models are not accurate enough for retrieving known agonists. To generate receptor models better suited for agonist screening, we developed a new knowledge- and pharmacophore-based modeling procedure that might partly simulate the conformational changes occurring in the active site during receptor activation. Receptor coordinates generated by this new procedure are now suitable for agonist screening. We thus propose two alternative strategies for the virtual screening of GPCR ligands, relying on a different set of receptor coordinates (antagonist-bound and agonist-bound states).  相似文献   

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In the present study, an in vitro regeneration protocol for Glossonema varians (Stocks) Benth. ex Hook.f. of family Asclepiadaceae was optimized. Cotyledonary nodes of in vitro cultured seedlings were used as explants for activation of axillary shoot buds. Axillary shoot buds were initially activated on 0.1 mg L?1 6-benzylaminopurine (BAP) and then multiplied on 0.05 mg L?1 BAP. Shoots were rooted in vitro on 1/4 strength Murashige and Skoog medium containing 0.1 mg L?1 2-naphthoxyacetic acid and 100 mg L?1 activated charcoal. The cultures were maintained in a 12 h photoperiod at 40–50 μmol m?2 s?1 spectral flux photon, 25–30?±?2°C, and 60% relative humidity (RH). Up to 80% of in vitro regenerated plantlets were acclimatized on soilrite in cotton-plugged culture tubes in the greenhouse. This protocol can be a useful method to mass propagate and conserve this rare plant to balance biodiversity in the desert ecosystem.  相似文献   

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Type material of several polychaete species described by Enrique Rioja from Mexican coasts are lost, and the current status of some species is doubtful. Nereis oligohalina (Rioja, 1946) was described from the Gulf of Mexico, but it has been considered a junior synonym of Nereis occidentalis Hartman, 1945, or regarded as a distinct species with an amphiamerican distribution. On the other hand, Nereis garwoodi González-Escalante & Salazar-Vallejo, 2003, described from Chetumal Bay, Caribbean coasts, could be confused with Nereis oligohalina. In order to clarify these uncertainties, Nereis oligohalina is redescribed based on specimens from the Mexican Gulf of Mexico, including a proposed neotype; further, Nereis garwoodi is redescribed including the selection of lectotype and paralectotypes, and Nereis confusa sp. n. is described with material from the Gulf of California. A key for the identification of similar species and some comments about speciation in nereidid polychaetes are also included.  相似文献   

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Swertia chirata is an endangered Gentian species used as herbal medicine for various health ailments including liver disorders, malaria, and diabetes. The depletion of S. chirata from the wild for such applications is a concern. Slow rates of propagation because of poor seed germination and low seed viability are presently limiting factors for its large-scale commercial cultivation. For commercial plantation and conservation of existing germplasm, in vitro multiplication is an attractive solution. The present investigation has achieved production of genetically uniform plants from the nodal explants. Shoot regeneration was obtained in shoot-inducing medium containing half-strength Murashige and Skoog’s basal medium supplemented with 0.44 μM 6-benzylaminopurine and 4.65 μM 6-furfurylaminopurine. The highest number of shoots, at 18 per explant, regenerated when media was further fortified with 10 mM KNO3 and 75 mg l−1 of casein hydrolysate. Tissue culture regenerated plantlets were successfully transferred to the field and produced viable seeds. Studies of chromosome number and a comparative analysis of the DNA fingerprinting profiles indicate genetic stability of the regenerated plants.  相似文献   

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The microstructure of hair of all mummified horses found in Northeastern Siberia has been studied for the first time in a comparative aspect by means of light optical and electron microscopy techniques. The possibility of using hair of horse mummies of different geological ages for a comparative analysis has been demonstrated. No fundamental differences were found in hair microstructure between the mummy of the “Bilibino” horse Equus sp. (geological age 58500 years) and mummified remains of the Lena horse Equus lenesis Russanov, 1968 (geological age 38 5000–29 500 years), which suggests their close relationship. It has been shown that morphological adaptations in the structure of the equine hair coat formed during the Pleistocene and Holocene under the specific climate conditions of Northeastern Siberia.  相似文献   

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Ethanolic extracts of Achyrocline satureioides have pronounced antioxidant activity mainly due to the presence of the flavonoid quercetin. However, direct topical application of the extract is not possible due to the presence of high amounts of ethanol. In this sense, nanoemulsions arise as an alternative for topical formulation associating molecules with limited aqueous solubility. This article describes the development of topical nanoemulsions containing either A. satureioides extract or one of its most abundant flavonoid, quercetin. Nanoemulsions composed of octyldodecanol, egg lecithin, water and extract (NEE), or quercetin (NEQ) were prepared by spontaneous emulsification. This process led to monodisperse nanoemulsions presenting a mean droplet size of approximately 200–300 nm, negative zeta potential, and high association efficiency. A study of quercetin skin retention using porcine skin which was performed using a Franz diffusion cell revealed a higher accumulation of quercetin in skin for NEE when compared to NEQ. Finally, the antioxidant activity of formulations was measured by thiobarbituric acid-reactive species and the APPH model. A lower lipoperoxidation for the extract in respect to quercetin solution was observed. However, no difference between NEQ and NEE lipoperoxidation could be seen. The protection against lipoperoxidation by the formulations was also measured in the skin, where lower formation of reactive species was observed after treatment with NEE. In conclusion, this study shows the formulation effect on the physicochemical properties of nanoemulsions as well as on the skin retention and antioxidant activity of quercetin.  相似文献   

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《Journal of bryology》2013,35(4):345-348
Abstract

Four cases of syncarpy are described from a single population of Bryum atropurpureum W. & M. A short discussion follows concerning the way in which this type of abnormality may arise, and it is suggested that an early cleavage in the young sporophyte affords the most reasonable explanation. The cases described are briefly compared with others that have been reported in the literature. Several species, belonging to unrelated genera, are instanced in this connexion.  相似文献   

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In Part 2 of this series of DFT optimization studies of α-maltotetraose, we present results at the B3LYP/6-311++G∗∗ level of theory for conformations denoted ‘band-flips’ and ‘kinks’. Recent experimental X-ray studies have found examples of amylose fragments with conformations distorted from the usual syn forms, and it was of interest to examine these novel structural motifs by the same high-level DFT methods used in Part 1. As in Part 1, we have examined numerous hydroxymethyl rotamers (gg, gt, and tg) at different locations in the residue sequence, and include the two hydroxyl rotamers, the clockwise ‘c’ and counterclockwise ‘r’ forms. A total of fifty conformations were calculated and energy differences were found to attempt to identify those sources of electronic energy that dictate stressed amylose conformations. Most stressed conformations were found to have relative energies considerably greater (i.e., ∼4 to 12 kcal/mol) than the lowest energy syn forms. Relative energy differences between ‘c’ and ‘r’ forms are somewhat mixed with some stressed conformations being ‘c’ favored and some ‘r’ favored, with the lowest energy ‘kink’ form being an all-gg-r conformation with the ‘kink’ in the bc glycosidic dihedral angles. Comparison of our calculated structures with experimental results shows very close correspondence in dihedral angles.  相似文献   

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The ethanolic and aqueous extracts from in vitro shoots of Quillaja saponaria Mol. (Quillay) were studied for their antifungal activity against the phytopathogenic fungus Botrytis cinerea Pers. These extracts reduced conidial germination and mycelial growth of B. cinerea, ethanolic extracts being more active than aqueous extracts. In addition, the damage areas produced by this fungus on tomato leaves and strawberry fruits pre-treated with quillay extracts were diminished. The fungitoxic effect of in vitro-grown quillay extract was similar to those obtained with commercial fungicides of both natural (BC-1000) and synthetic (iprodione–dicarboximide) origin. On the other hand, the antifungal action of quillay extracts obtained from adult trees naturally grown was only slightly superior to the fungitoxic activity of the extract from in vitro plants. HPLC analysis of the extract showed that it contained saponins and some phenolic compounds such as chlorogenic, caffeic, vanillic, and salicylic acids, and scopoletin, which have been identified as antifungal agents on phytopathogenic fungi. The results obtained in this work, suggests that extracts of in vitro-grown quillay have an important protective effect against B. cinerea and support the use of an in vitro culture system as a biotechnological alternative to obtain environmental safe antifungal quillay extracts to control B. cinerea, contributing to the preservation of this indigenous Chilean species.  相似文献   

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Quantitative variation of species-specific subtelomeric repeat Spelt1 was studied in the progeny of an individual plant from the introgressive line Triticum aestivum × Aegilops speltoides. In the progeny, no cases of the Spelt1 increased content were observed. On the contrary, in some cases statistically significant decrease of the repeat copy number was detected. It seems likely that the mechanisms of the Spelt1 elimination involve either the selection at the gamete level versus the increase of the satellite DNA content in the telomeres, or intramolecular (within one chromatid) homologous recombination.  相似文献   

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Oreocharis mileense (W.T. Wang) M. Möller & A. Weber is endemic to China and was considered to be extinct because it had not been seen in the wild since the first collection in 1906. In 2006, the species was rediscovered in Shilin County, Yunnan Province. Oreocharis mileense was considered critically endangered for its narrow geographic range and extremely small population. An efficient method to preserve plant germplasm by in vitro culturing of O. mileense has not been reported. In this study, an orthogonal array with three factors (6-benzyladenine, BA; α-naphthaleneacetic acid, NAA; and sucrose), at four levels was performed, and shoot induction as well as shoot proliferation were recorded. The results were analyzed to determine the most significant components and the optimum combination for micropropagation of O. mileense. The results showed that: (1) organogenesis was easily induced by different combinations of plant-growth regulators and sucrose; (2) NAA and sucrose had the most significant effect on shoot induction and shoot multiplication, and (3) the optimum induction and proliferation media were 0.5 mg L?1 BA + 0.2 mg L?1 NAA?+?30 g L?1 sucrose and 1 mg L?1 BA + 0.1 mg L?1 NAA?+?30 g L?1 sucrose, respectively.  相似文献   

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