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1.
Pollen characters were analyzed in 16 cenopopulations of Potentilla bifurca L. in five provinces of the Altai-Sayan Mountain Region. As a result, two groups of cenopopulations, western and eastern, have been recognized. Both groups are characterized by a high intrapopulation (44.7–63.9%) and a lower interpopulation (11.4–42.2%) variability. The observed similarity between groups of cenopopulations of P. bifurca from different geobotanical provinces is determined by their common origin from the Pliocene-Pleistocene steppe communities.  相似文献   

2.
On the basis of the system of ordination for the geographic zonal and provincial replacement of types of pine forests, gradients, and some geographical trends of the main parameters of the morphostructure, the growth and viability of the cenopopulations of common heather Calluna vulgaris (L.) Hull between various subzones of the Russian Plain and the western part of Western Siberia (Tobolsk area) have been revealed.  相似文献   

3.
The condition of cenopopulations of the relict of nemoral (Pliocene) flora Menispermum dauricum DC. is considered. Three new habitats of the species are found in Western Transbaikalia. It is shown that, although the species is an ecotopic patient, local cenopopulations on mountain-steppe slopes are influenced by destructive exogenous geomorphological processes.  相似文献   

4.
The assessment of ecogeographic variability and differentiation of 22 cenopopulations of Japanese dwarf pine Pinus pumila (Pall.) Regel (Pinaceae) on the Kamchatka Peninsula and in Koryakia has been carried out in regard to morphological and phenotypic characters of mature seed cones. The viability of seeds in the cones of ten populations has been determined by a radiographic method. A latitudinal nature of phenotypic differentiation of cenopopulations in the region has been revealed. Lower seed viability related to a high percent of seeds without embryos or with underdeveloped embryos has been recorded in the northeastern populations. The average share of viable seeds in the region is 52% and in the northeastern populations it reaches only 6–24%.  相似文献   

5.
Vitality of individuals and cenopopulations of the rare relict species Sophora flavescens Soland. was studied. To characterize the vitality of individuals of the species, the following parameters are used: number and length of the shoots, number of leaves on a shoot, as well as ratio of the leaf length to its width. Different combinations of these quantitative parameters areused to determine the marks of vitality for each individual. When estimating the vitality of cenopopulations of the species the important characteristics include the type of population, average marks of the vitality of the individuals in cenopopulation, completeness of the age range, the presence of the mixed self-maintenance, and abundance of the species in the community. It is noted that the high vitality of the individuals is observed in cenopopulations of the young type and transitional type to the mature and maturing ones.  相似文献   

6.
Fifteen Brunnera sibirica cenopopulations have been studied. Morphological and genetic investigations reveal increasing variability and high level of correlation between morphological features (according to decreased sizes of vegetation organs) during the first years after deforestation in fir and aspen forests. High morphological and genetic variability is typical for mountain fir forests, pine–birch, and pine forests.  相似文献   

7.
This article presents the results of an analysis of ontogenetic and vitality structure of seven cenopopulations of Oxytropis sulphurea (Fisch. ex DC.) Ledeb. in the high-altitude conditions of Rydny Altai (Ivanovsky and Prohodnoi ridges) and the Saur Ridge. In the study of the demographic structure it has been determined that most populations from undisturbed habitats are characterized by left-side spectrums with maximums on juvenile or immature individuals. The changes in the structure of the studied ontogenetic spectrums of this species depend largely on the presence of anthropogenic influence. Grazing pressure has led to the formation of spectrums with a maximum on g3 plants. The vitality type of the O. sulphurea populations varies from exuberant to depressed; the depressed and balanced types of vitality prevailed. Intensive seed propagation provides a stable existence of O. sulphurea in the high-mountain alpine zone. The results of our study show that O. sulphurea is an alpine-meadow species which has strict ecological and cenotic propensity for alpine meadows with the prevalence of Festuca kryloviana, Anthoxanthum alpinum, and Schulzia crinite and shrub tundras with Dryas oxyodonta.  相似文献   

8.
Plant communities with Astragalus sericeocanus have been studied. Data on the ontogenetic structure and quantity of cenopopulations, as well as the seed productivity of their individuals, are given. It has been revealed that the habitats on the northern shore of Lake Baikal are characterized by high phytocoenotic diversity with the dominance and codominance of A. sericeocanus. The state of cenopopulations and parameters of seed productivity indicate that the northern habitats of Lake Baikal have more favorable conditions due to the optimal climatic characteristics for the growth and development of the species.  相似文献   

9.
Abramova  L. M.  Ilyina  V. N.  Mustafina  A. N.  Karimova  O. A. 《Biology Bulletin》2019,46(10):1199-1205
Biology Bulletin - Abstract—The results of the study of 23 natural cenopopulations of Cephalaria uralensis (Murr.) Schrad. ex Roem. et Schult., a rare subendemic species of the Eastern...  相似文献   

10.
Zeng X  Yuan Z  Tong X  Li Q  Gao W  Qin M  Liu Z 《Molecular biology reports》2012,39(5):5737-5744
Oryzoideae (Poaceae) plants have economic and ecological value. However, the phylogenetic position of some plants is not clear, such as Hygroryza aristata (Retz.) Nees. and Porteresia coarctata (Roxb.) Tateoka (syn. Oryza coarctata). Comprehensive molecular phylogenetic studies have been carried out on many genera in the Poaceae. The different DNA sequences, including nuclear and chloroplast sequences, had been extensively employed to determine relationships at both higher and lower taxonomic levels in the Poaceae. Chloroplast DNA ndhF gene and atpB-rbcL spacer were used to construct phylogenetic trees and estimate the divergence time of Oryzoideae, Bambusoideae, Panicoideae, Pooideae and so on. Complete sequences of atpB-rbcL and ndhF were generated for 17 species representing six species of the Oryzoideae and related subfamilies. Nicotiana tabacum L. was the outgroup species. The two DNA datasets were analyzed, using Maximum Parsimony and Bayesian analysis methods. The molecular phylogeny revealed that H. aristata (Retz.) Nees was the sister to Chikusichloa aquatica Koidz. Moreover, P. coarctata (Roxb.) Tateoka was in the genus Oryza. Furthermore, the result of evolution analysis, which based on the ndhF marker, indicated that the time of origin of Oryzoideae might be 31 million years ago.  相似文献   

11.
Summary  Three closely affiliated species of Heterospathe Scheff. (H. elegans (Becc.) Becc., H. humilis Becc. and H. versteegiana Becc.) from New Guinea are revised. They are reduced to a single species which is divided into two subspecies, and the new combination H. elegans subsp. humilis (Becc.) M. S. Trudgen & W. J. Baker is made. The subspecies can be readily distinguished by their growth habit. Epitypes are designated for the three previously published names, as informative material on the habit is not included in the existing type specimens. A new, potentially related species is described as H. pullenii M. S. Trudgen & W. J. Baker.  相似文献   

12.
A molecular genetic analysis of soriz genotypes (Sorghum oryzoidum), its parental form Sorghum bicolor (L.) Moench (grain sorghum), possible parents (Sorghum sudanense (Piper.) Stapf. (Sudan grass) and Oryza sativa L. (Rice planting), as well as its closest relatives, has been carried out with the use of microsatellite loci of sorghum and rice. Based on the obtained data, the genetic distances were calculated and the examined species were clustered. It was shown that soriz did not carry rice DNA fragments, but its genome contained DNA fragments, which belonged to Sudan grass. This confirms that the origin of soriz is associated with representatives of Sorghum sudanense.  相似文献   

13.
The acid-base properties of dioxane lignins from the roseroot stonecrop (Rhodiola rosea L.) and the saw-wort (Serratula coronata L.) have been studied by spectrophotometrically determining the ionization constants for phenol hydroxyl groups. A correlation between the molecular masses of the fractions of lignins and their acid-base properties has been established.  相似文献   

14.
This paper deals with taxonomy and phylogenetics of the genus Eurycletodes Sars, 1909 (Copepoda: Harpacticoida: Argestidae). Samples, collected from the southeast Atlantic on board RV “Meteor” during the cruises DIVA-1 (M48/1) and DIVA-2 (M63/2), contain specimens of Eurycletodes. Eurycletodes is characterized as a monophylum by A1 segments III + IV fused, basal seta of md palp lost, exp of md palp reduced to 1 seta or completely lost. Similarly, the subgenera Eurycletodes (Eurycletodes) and Eurycletodes (Oligocletodes) are characterized as monophyletic by the loss of the inner seta on P1 exp2 (apomorphic to E. (E.)) and the absence of the inner seta on P5 endopodal lobe (apomorphic to E. (O.)). Eurycletodes profundus is renamed as E. (O.) profundus. Eurycletodes ephippiger is the only species of the genus without subgeneric designation. Eurycletodes (O.) diva sp. nov. is described. The new species differs from described species of the genus by a larger body size, P5 endopodal lobe only slightly protruding, last segment of A1 with 2 outer setae, furcal rami elongated between setae VII and IV. The occurrence of 2 specimens of Eurycletodes (O.) diva sp. nov. at 2 sites separated by the Walvis Ridge supports the hypothesis that geographic obstacles do not prevent harpacticoid copepods from spreading in the deep sea.  相似文献   

15.
16.
A new monotypic subgenus, Premicrodispulus subgen. n., with the type species Premicrodispus reductus sp. n., and four new species of the nominative subgenus of the mite genus Premicrodispus, P. (Premicrodispus) paradoxus sp. n., P. (P.) heterocaudatus sp. n., P. (P.) obtusisetosus sp. n., and P. (P.) incisus sp. n., collected in soils of Turkmenistan are described. The subgenus Premicrodispulus subgen. n. differs from the nominative subgenus in the presence of 3 setae on genu I (seta l″ absent) and 1 seta on genu II (setae d and l″ absent). Premicrodispus (Premicrodispus) paradoxus sp. n. differs from all the species of the genus in the presence of solenidion on tarsus III. P. (P.) heterocaudatus sp. n. is most similar to P. longisetosus (Mahunka, 1970), but differs in the setae ps3 distinctly longer than ps 1 (in P. longisetosus, ps 3 and ps 1 are similar in length). P. (P.) obtusisetosus sp. n. is most similar to P. montanus Khaustov, 2006, but differs in obtuse setae c 1, e, and f (in P. montanus, these setae are pointed); P. (P.) incisus sp. n. is most closely related to P. longisetosus (Mahunka, 1970), but differs in the presence of distinct excavations on the posterior margin of tergites C and D (in P. longisetosus, excavations are absent).  相似文献   

17.
The helminthological study of 26 Eurasian badgers (Meles meles L.) in the Basque Country (northern Spain) revealed the presence of two trematode (Euryhelmis squamula and Brachylaima sp.), three cestode (Atriotaenia incisa, Mesocestoides sp. and Taenia sp.) and five nematode (Aonchotheca putorii, Physaloptera sp., Molineus patens, Uncinaria criniformis and Strongyloides sp.) species. All 15 individuals analysed for Trichinella sp. were negative. The coprological analysis (flotation and migration) revealed the excretion of strongylid, capillariid and trematode eggs, and Crenosoma sp. and Angiostrongylus sp. larvae. No sex- or age-related differences were found in the parasite burden or egg and larvae excretion. A. incisa and M. patens abundances were positively correlated, both species being negatively correlated with badger weight. The presence of adults of U. criniformis and strongylid eggs in faeces was not independent. Badgers excreting Angiostrongylus larvae were in poorer condition than those not excreting.  相似文献   

18.
In Argentina, the Andean biogeographic region accommodates the most diverse population of fleas in the country. The Craneopsyllinae (Siphonaptera: Stephanocircidae) represent one of the most commonly found subfamilies in this region and show some endemism and high diversity. Plocopsylla is the most diverse genus of Craneopsyllinae; it includes 10 species mainly distributed in the Patagonian subregion, which parasitize sigmodontine rodents (Rodentia: Cricetidae). We describe and illustrate the morphology of the aedeagus in species of Plocopsylla that belong to the ‘angusticeps–lewisi’ complex. This character is of diagnostic value in differentiating among species. A new species of this complex, Plocopsylla (Plocopsylla) linardii sp. n., is described and identified by the shape and chaetotaxy of the distal arm of sternite IX, as well as by the shape of the median dorsal lobe of the aedeagus. New host associations for this complex and range extensions for most of its species are reported. Plocopsylla (P.) silewi is recorded for the first time in Argentina. The southern limits of the distributions of Plocopsylla (P.) lewisi and Plocopsylla (P.) wilesi are extended to Santa Cruz Province. The angusticeps–lewisi complex is found for the first time in San Juan Province. The information may be useful in epidemiological studies of flea‐borne diseases.  相似文献   

19.
In the course of a taxonomic revision of the Doronicum clusii agg. (Asteraceae), we present an updated and commented distribution map of D. clusii (All.) Tausch and D. stiriacum (Vill.) Dalla Torre from the Alps and Carpathians, completed with information on biogeography and taxonomy. We show that D. stiriacum was erroneously indicated for the Carpathians south and southeast of the Rodna Mountains in Romania and for the Western Alps. In the Western Carpathians, it has only been rarely mentioned for the Nízke Tatry (Lower Tatras) and the Belianske Tatry (Belá Tatras) in Slovakia.  相似文献   

20.
The results of studies of the vegetative cover and ontogenetic composition of the cenopopulations of Picea obovata Ledeb. and Larix sibirica Ledeb. in the Gorno-Khadytinskii Forest Reserve, which is the refugium of the northern taiga forests of Western Siberia, have been summarized. According to the Brown–Blanke system, two associations of forests were identified and described, as well as two tundra associations, for comparison. The unique association of the Aconito septentrionalisPiceetum obovatae taiga forests Zaugolnova et Morozova 2009 were analyzed in detail, and a comparison of these associations was carried out in the Gorno-Khadytinskii and Pechoro-Ilychskii reserves, where these forests are the reference standards of the zonal-type forests. An estimate of the ontogenetic composition of the cenopopulations of P. obovata Ledeb. and L. sibirica Ledeb. is given, as well as the absolute age of the trees of these species.  相似文献   

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