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1.
The phytochemical investigation of the ethyl acetate fraction of Polygala longicaulis Kunth resulted in the isolation and identification of two dihydrostyryl-2-pyrones (12). This is the third species of the Polygala L. genus, along with Polygala altomontana Lüdtke, Boldrini & Miotto and Polygala sabulosa A.W. Benn., to present the accumulation of dihydrostyryl-2-pyrones. The data reported herein make an important contribution to the chemotaxonomy of this genus. This is the first report of dihydrostyryl-2-pyrone (1) and dihydrometisticin (2) in P. longicaulis and the first report of dihydrometisticin in the genus Polygala. Furthermore, this is the first grouping of non-xanthone-producing Polygala species.  相似文献   

2.
Polygala pauciramosa, a new species from the Federal District and the state of Goiás is described, illustrated, and compared with related species of Polygala subgenus Hebeclada. The new species is an herb that grows in seasonally to permanently wet savannas. A key to the species of Polygala subgenus Hebeclada from Goiás state, Brazil is provided.  相似文献   

3.
The genus Polygala is one of the seven Polygalaceae genera that occur in the Brazilian flora, covering approximately 110 species. During the taxonomic review of Polygalaceae in Southern Brazil, difficulties were found when classifying species with very similar morphology, and morphological data alone could not clarify these interspecific relationships. In this context, inter-simple sequence repeat (ISSR) molecular markers were used in an attempt to characterize the genetic diversity and relationships among Polygala species. Nine Polygala species were analyzed using six selected ISSR primers that generated a total of 75 bands (100% polymorphic). The relationships were evaluated by dendrograms using the unweighted pair group method using arithmetic averages algorithm. The use of ISSR to solve the taxonomic problems was very useful for the Brazilian Polygala species. This is the first report of a molecular characterization of the Brazilian Polygala species to successfully group the different species. The ISSR results are in agreement with the morphological evidence of a new Polygala species from Southern Brazil.  相似文献   

4.
5.
Polygala peshmenii Eren, Parolly, Raus & Kürschner is described and illustrated as a new species from Antalya province in south‐west Anatolia, Turkey. Within subgenus Polygala section Polygala, it seems to be taxonomically quite isolated. As far as the Flora of Turkey area is concerned, technical comparison can be made with the informal P. alpestris Rchb. and P. vulgaris L. groups. The habitat conditions of P. peshmenii and its conservation status are considered. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 82–86.  相似文献   

6.
Polygala subgen. Chamaebuxus comprises five perennial species, distributed in Europe and northwestern Africa. Polygala webbiana was hitherto thought to be endemic to Morocco. In this paper, we report the first known population of this species in Europe, present in the province of Málaga (Spain). Detailed pictures of the flower, fruit, and seed are presented, as well as a map of the whole distribution. Moreover, a key to identify the species of Polygala subgen. Chamaebuxus is provided. The names P. chamaebuxus and P. vayredae are lectotypified.  相似文献   

7.
The new species Pelargonium elandsmontanum is a local endemic from Elandsberg Nature Reserve near Malmesbury in the Western Cape Province, South Africa. One of six species of sect. Hoarea with just the posterior two petals developed, it resembles P. ternifolium in its trifoliolate leaves and pink petals but is distinguished from that species by the short, stout petioles, rhombic, acute leaflets with the upper surface glabrous or with spreading hairs (vs cuneate, apically incised leaflets with both surfaces adpressed-hairy), and five (vs four) fertile stamens.  相似文献   

8.
扑草净对远志幼苗根系活力及氧化胁迫的影响   总被引:4,自引:0,他引:4  
以远志(Polygala tenuifolia Willd.)为材料,应用组织化学和生物化学的方法研究不同浓度扑草净(0—400 mg/L)对远志幼苗生长、根系活力、膜脂过氧化、活性氧含量及抗氧化酶活性等的影响。10 mg/L扑草净对远志幼苗根系活力、细胞膜完整性及活性氧的积累几乎无显著影响,而25—400 mg/L扑草净处理则显著增加活性氧的积累,明显抑制根系活力且破坏细胞膜完整性;上述结果进一步被膜脂过氧化、质膜完整性、活性氧产生(O.2-和H2O2)的非损伤组织化学染色所证明。远志幼苗可通过多种抗氧化酶(SOD、POD、CAT、APX等)和非酶抗氧化剂(如脯氨酸)的相互协调作用,清除低浓度扑草净胁迫诱发产生的活性氧,减轻对细胞的伤害。研究结果表明,发芽期是远志对扑草净处理的敏感时期,较为安全的扑草净临界浓度为10 mg/L;25mg/L扑草净处理即引起远志幼苗氧化胁迫和膜脂过氧化,使细胞膜的完整性受到破坏,根系活力下降,抑制了远志幼苗的生长发育。该研究为远志抗除草剂胁迫机制及其栽培过程中除草剂的安全合理使用提供理论依据。  相似文献   

9.
Boletus roseoflavus is described as a new species based on morphological and molecular studies of the type collection and additional materials. Boletus roseoflavus is morphologically distinct from other related species (B. regius, B. appendiculatus, and B. speciosus) by its light pink, pink, or rosy pileus, lemon yellow or golden yellow context, and lemon yellow or light yellow, enlarged download stipe with yellow reticulation. Phylogenetic analyses based on ribosomal DNA internal transcribed spacer regions and nuclear large subunit ribosomal RNA indicate that B. roseoflavus belongs to Boletus section Appendiculati.  相似文献   

10.
Many terrestrial orchids are relatively rare, and their populations are small and spatially isolated. Population genetics theory predicts that populations of such species, affected historically by random genetic drift, would maintain low levels of genetic diversity and exhibit a high degree of among-population divergence. To test this prediction, I used enzyme electrophoresis. Genetic diversity within populations of the four rare, terrestrial orchids Gymnadenia cucullata (four populations) and its congener G. camtschatica (four populations), Amitostigma gracile (four populations in one region and three in another region), and Pogonia minor (three populations each in two regions) was investigated in South Korea at the landscape level. As predicted, populations of the four species harbor low levels of genetic diversity within populations: the mean percentage of polymorphic loci, %P, the mean number of alleles per locus, A, and the average expected heterozygosity, H e, were 12.5%, 1.13, and 0.036 for G. cucullata, respectively; 18.2%, 1.18, and 0.067 for G. camtschatica; 3.0%, 1.04, and 0.009 for A. gracile; and 2.7%, 1.06, and 0.014 for P. minor. Except for G. camtschatica (F ST = 0.000), a significantly high degree of genetic divergence between conspecific populations was detected in the other three species: F ST = 0.081 for G. cucullata; 0.348 and 0.811 in two regions for A. gracile; and 0.469 and 0.758 in two regions for P. minor. In addition, individuals within populations are highly structured in the four species (overall F IS = 0.276 for G. cucullata; 0.308 for G. camtschatica; 0.758 for A. gracile; and 0.469 for P. minor), suggesting that selfing, biparental inbreeding, and/or consanguineous mating have occurred in populations of the four species. With the exception of G. camtschatica, an allele at a locus is fixed in a population, whereas alternative alleles with low or high frequencies are detected in another population across the landscape. My results suggest that evolutionary histories of G. cucullata, A. gracile, and P. minor are different from G. camtschatica. Historical genetic drift would be an important force shaping the genetic structure of the Korean populations of G. cucullata, A. gracile, and P. minor. For G. camtschatica on Ulleung Island, relatively higher levels of genetic variation within populations compared to its congener G. cucullata (H e = 0.067 vs. 0.036) and little evidence of population genetic structure among populations (F ST = 0.000) suggest that individuals were, presumably, once continuously distributed on Ulleung Island, and populations have recently been isolated by habitat fragmentation through natural succession (e.g,. probably the encroachment of woody vegetation on grasslands) or human-mediated disturbances (e.g., collections). Thus, conservation strategies for the four species should be differently developed in order to preserve genetic diversity in South Korea.  相似文献   

11.
12.
《Flora》2014,209(5-6):250-259
Inselbergs support highly specialized vegetation with many endemic species. Here we studied by an integrated approach a rare and threatened species from Brazilian inselbergs. Pitcairnia encholirioides (Bromeliaceae) is included in the Red Book of Brazilian Flora, in the ‘Endangered’ category. Only one single population on unprotected private property was known at the beginning of our study. We studied several life-history traits including clonal growth, reproductive biology, seed germination and cryopreservation, and genetic diversity. Pitcairnia encholirioides has the phalanx type of clonal growth strategy. Its self-incompatible flowers are successfully pollinated by hummingbirds. However, less than 5% of clonal fragments produced flowers. Seeds can be wind-dispersed, but most of them are dispersed by gravity and fall close to the mother plant. The percentage and speed of germination were significantly affected by different temperatures, water potential, and red:far-red light ratios, although more than 80% of seeds germinated under optimal physiological conditions. The genetic diversity was very low (Hsp = 0.09) and the population was highly structured (ΦST = 0.51). The combination of dispersal mode and environmental conditions seems to be the main factor leading to the rarity of P. encholiroides. Low genetic diversity combined with small population size and low reproductive capacity suggest that the species is highly susceptible to environmental disturbance. Similarly to P. encholiroides, many species from Brazilian inselbergs are restricted to only a few localities. For more widely distributed species, a higher genetic diversity among populations has been consistently detected. The pattern of low gene flow of many species with small distributions highlight the importance of population-based conservation strategies for such taxa the areas of occurrence of which being naturally fragmented at inselberg sites. We discuss some strategies that may help in conservation of such species.  相似文献   

13.
Knowledge of how natural and anthropogenic factors can limit the distribution of rare species is key to develop conservation strategies. We show data on how both factors potentially affect the distribution of a rare high Andean orchid. We chose Masdevallia coccinea as a model because it is endangered and the most commercialized species of the entire genus. Using ecological niche modeling, we confirm its rarity, with a restricted potential occurrence equivalent to only 0.00005 % of South America, 0.0003 % of the Andes, and 0.0009 % of Colombia. We projected the future potential occurrence of M. coccinea and found that it can have a reduction of 43.49 % in the best-case scenario and 89.06 % in the worst-case scenario in 2100. We describe the flowering and fruiting phenologies and demonstrate that the precipitation two months before may determine the first one. Masdevallia coccinea is a rewardless species and, unlike most Pleurothallidinae species, we show that it is self-compatible but non-autonomous selfer. Thus, it is dependent on biotic pollination, performed only by Leucophenga sp. (Drosophilidae: Diptera) which has low efficiency (8.6 % of fruit set). This is the first pollinator report for the genus. While self-compatibility may be related to reproductive assurance, apparently inbreeding depression may affect populations since selfed fruits had less viable seeds. Nevertheless, self-pollination can be avoided by the retention of the anther cap on pollinia, giving more time until the pollinator flies away to another flower. We consider that the rarity of M. coccinea may be a result of both anthropogenic (habitat loss, climate change, and overcollection) and natural factors (high elevation distribution, self-compatibility, rewardless strategy, pollinator specificity, and low fruit set). The several new facets investigated here can be used for future conservation strategies of this emblematic species as well as other high Andean threatened species.  相似文献   

14.
The mycorrhizas of 12 species of Polygala (Polygalaceae), including herbs, subshrubs and one shrub, collected from Germany, Mallorca (Spain) and Malta, were investigated by morpho‐anatomical and molecular methods. Aseptate hyphae, arbuscules and vesicles indicate an arbuscular mycorrhiza in all species examined. Hyphal spread in Polygala is predominantly, but not exclusively, intracellular and comprises three characteristic stages of colonization: (i) intracellular, linear hyphal growth in a cascading manner after penetration towards the penultimate parenchyma layer (layer 2), (ii) initially linear hyphal growth in the cells of layer 2 from where hyphal branches repeatedly penetrate the anatomically distinct innermost parenchyma layer (layer 1), forming arbuscule‐like structures therein which are subject to degeneration, (iii) more branches from the linear hyphae in layer 2 develop, but coil and make contact to the layer outside layer 2 (layer 3) in which arbuscule‐like structures similar to those in layer 1 form and degenerate. This general colonization pattern differs in details between the species, and critical comparisons, in particular between the woody P. myrtifolia, the herbaceous Polygala spp. and the mycoheterotrophic Epirixanthes spp. (Polygalaceae) suggest an evolutionary shift of mycorrhizal features within the family towards an optimization of plant benefit through the fungus. Based on the molecular marker 18S rDNA mycorrhizal fungi detected in roots of Polygala spp. are largely restricted to five clades of Glomeraceae 1 (Glomus Group A). This result rejects the hypothesis of a strict symbiotic specificity in Polygalaceae but may stimulate a discussion on functionally compatible groups of fungi.  相似文献   

15.
The Chilean Puya species (Puyoideae, Bromeliaceae) constitute an early diverging group within the genus and thus are key taxa for the understanding of the early evolution and biogeography of Puya. However, a modern taxonomic treatment including information from molecular phylogenetic studies is still lacking. Here, a taxonomic revision of the Chilean species of Puya is presented based on morphological, molecular, and biogeographic data. A re-evaluation of the widely applied concept of P. berteroniana led us to the conclusion that the type of P. berteroniana is of hybrid origin and is maintained as Puya × berteroniana. Our studies revealed that the name P. berteroniana has been widely misapplied to what in fact is the northern metapopulation of P. alpestris, which is here described as a new subspecies, Puya alpestris subsp. zoellneri, a member of subgenus Puya. A lectotype is designated for Puya copiapina and a neotype for P. chilensis. Altogether, six Puya species, two subspecies, four varieties and one hybrid taxon are recognized for the Chilean flora in this revision: P. alpestris subsp. alpestris and subsp. zoellneri; P. boliviensis; P. chilensis; P. gilmartiniae; P. coerulea var. coerulea, var. intermedia, var. monteroana, and var. violacea; P. venusta; and P. × berteroniana. A key is provided for their identification.  相似文献   

16.
Two species of echinostomatid trematodes from Paraguayan birds are redescribed: these are Drepanocephalus spathans Dietz, 1909 from Phalacrocorax olivaceus and Paryphostomum segregatum Dietz, 1909 from Coragyps atratus. The genera Drepanocephalus Dietz, 1909 and Paryphostomum Dietz, 1909 are redefined and the species previously assigned to them reviewed. Paryphostomum mexicanum (Lamothe-Argumedo &; Pérez-Ponce de León, 1989) n. comb. and P. parvicephalum (Rietschel &; Werding, 1978) n. comb. are transferred from Drepanocephalus to Paryphostomum. A key to the species of Paryphostomum is presented, and the nominal species of Echinostoma Rudolphi, 1809, Nephrostomum Dietz, 1909 and Artyfechinostomum Lane, 1915 previously ascribed to this genus are commented upon. New combinations for species previously attributed to Paryphostomum are: Echinostoma pentalobum (Verma, 1936) n. comb.; E. baiyangdienense (Ku, Pan, Chiu, Li &; Chu, 1973) n. comb.; Nephrostomum dollfusi (Agarwal, 1959) n. comb.; and Artyfechinostomum neotoma (Jain, 1953) n. comb. Species attributed to Paryphostomum which are here considered species inquirendae are: Paryphostomum (Lepustomum) mehrii Jain, 1953 sp. inq.; P. fragosum (Dietz, 1909) sp. inq.; P. horai Baugh, 1950 sp. inq.; P. huaccaci Ibáñez, 1974 sp. inq.; P. agrawali Gupta &; Singh, 1986 sp. inq.; P. siddiqui Gupta &; Singh, 1986 sp. inq.; P. durgensis Sapre, 1969 sp. inq.; and P. globorchum Oshmarin, 1970 sp. inq.  相似文献   

17.
Pempheris gasparinii sp. n. is described from five specimens, 59.1–68.0 mm in standard length. It is only known to occur in the shallow reefs of Trindade Island, 1200 km east of the Brazilian coast, in the southwestern Atlantic. Pempheris gasparinii is the third recognized species of Pempheris in the Atlantic Ocean. This new species is morphologically similar to its close relative, Pempheris poeyi, differing by the number of lateral-line scales (51–54 in Pempheris gasparinii vs. 47–49 in Pempheris poeyi), scales below lateral line (10–11 vs. 9), circumpeduncular scales (11–12 vs. 13), head and caudal peduncle lengths (2.7–3.3 vs 3.5–4.0 in head length). Moreover, Pempheris gasparinii shows a 4% genetic divergence from Pempheris poeyi at the cytochrome oxidase I locus (COI), consistent with a lineage split at the beginning of the Pleistocene. This new species represents the 12th endemic fish species from Trindade Island.  相似文献   

18.
A new species of troglobitic harvestman, Iandumoema smeagol sp. n., is described from Toca do Geraldo, Monjolos municipality, Minas Gerais state, Brazil. Iandumoema smeagol sp. n. is distinguished from the other two species of the genus by four exclusive characteristics – dorsal scutum areas with conspicuous tubercles, enlarged retrolateral spiniform tubercle on the distal third of femur IV, eyes absent and the penial ventral process slender and of approximately the same length of the stylus. The species is the most highly modified in the genus and its distribution is restricted only to caves in that particular area of Minas Gerais state. The type locality is not inside a legally protected area, and there are anthropogenic impacts in its surroundings. Therefore, Iandumoema smeagol sp. n. is vulnerable and it must be considered in future conservation projects.  相似文献   

19.
Rubus canduliger is described as a new regional bramble species belonging to the seriesDiscolores. It has been recognized in the Netherlands as a distinct species for more than 70 years but identified as the central EuropeanR. grabowskii. The latter, however, differs by its tapering prickles, regular leaves with longer petiolule of the terminal leaflet, broader, often pyramidal inflorescence, and white or pink flowers with carpels hairy at the top.R. canduliger has a well-defined range north of the Rhine river around Arnhem where it occurs in urban and other disturbed habitats. Historical events, e.g. transport of young trees in the 16th century may explain most records south of the Rhine river, 25–50 km outside the main range. The ecology and phytosociology of the new bramble are discussed. Its distribution is compared toR. trichanthus, another regional species with a similar range asR. canduliger, but occurring in more natural habitats. In pseudogamous European blackberries (Rubus sectionRubus =R. fruticosus agg.), range size is considered to be related to the age of the species. Several widespread species have disjunct distribution ranges that are suggested to be the result of long-distance dispersal by migratory birds but unintentional anthropogenic transport of seeds may be involved as well. We hypothesize that in northwestern Europe fragmentation of continuous ranges of widespread species was caused by ongoing deforestation and subsequent degradation (acidification) of originally base-rich sandy and loamy soils from the Iron Age onward. Many regional species, however, have originated and spread in the resulting man-made landscapes. A classification of range types of brambles differing in size and internal structure is presented.  相似文献   

20.
Perreyia flavipes Konow, 1899 (Pergidae: Perreyinae) is a sawfly species with gregarious larvae commonly found in open areas in southern Brazil through Uruguay and northern Argentina. The combination of highly gregarious larvae with the production of a variety of toxins in P. flavipes has led to severe cases of intoxication in a variety of livestock species. Over the years, considerable information was discovered on the larval natural history of P. flavipes; however, virtually nothing is known about the adult behavior, particularly because of its short life-span. In this study, we report on the first extensive study on the adult behavior of P. flavipes, including movement, mating (with oviposition and maternal care), and thanatosis. Our results show some unusual behavioral adaptations presented by P. flavipes, such as irregular activity behavior (i.e., deficient gait pattern), thanatosis behavior-like display, and primitive maternal care. Individual behavioral acts are described and compared among sexes, and their potential functions are discussed.  相似文献   

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