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1.
The genetic diversity and population structure of the endemic species of Baikal Siberia Oxytropis triphylla, O. bargusinensis, and O. interposita were studied for the first time on the basis of the nucleotide polymorphism of intergenic spacers psbA–trnH, trnL–trnF, and trnS–trnG of chloroplast DNA. All populations of these species were characterized by a high haplotype (0.762–0.924) and relatively low nucleotide (0.0011–0.0022) diversity. Analysis of the distribution of variability in O. triphylla and O. bargusinensis showed that there was no significant genetic differentiation between populations of each species; the gene flow was 4.43 and 8.91, respectively. The high level of genetic diversity in the studied populations indicates a relatively stable state of these populations. A study of the phylogenetic relationships of closely related species confirms the concept of the origin of O. bargusinensis and O. tompudae as a result of intersectional hybridization of the species of the sections Orobia and Verticillares.  相似文献   

2.
The subgenus Pocusogetus Rtt. of the genus Otiorhynchus Germ. is revised. The subgenus includes O. rosti Strl., O. shapovalovi Davidian et Yunakov, O. obsulcatus Strl., O. fischtensis Rtt., and O. gusakovi sp. n. closely related to O. fischtensis (both from Mt. Fisht, the Western Caucasus). O. fischtensis is transferred from the subgenus Vicoranius Rtt., its lectotype is designated. A key to species of Pocusogetus is given. The systematic position of the subgenera Pocusogetus and Vicoranius in the genus Otiorhynchus is discussed. New data on the geographical distribution and ecology of the little-known species of the subgenera Obvoderus Rtt., Pseudoprovadilus Magnano, and Clypeorhynchus Yunakov et Arzanov are given. Some features of ecological differentiation between Otiorhynchus species in the alpine and subalpine zones of the Caucasus are discussed.  相似文献   

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4.
We carried out an allozyme analysis to investigate polymorphism and genetic structure of the populations of D. incarnata and D. ochroleuca in regions of their joint growth in Russia and Belarus. We found that D. ochroleuca individuals in the populations of the Urals and Siberia, which are distant fragments from the main range of the species, do not differ significantly from individuals within the main part of the area (Belarus) on the basis of the allelic composition of eight gene loci. We revealed that D. ochroleuca and D. incarnata are differentiated by different alleles of the GDH locus. Thus, we established a genetic marker suitable to distinguish these closely related taxa. In addition to the GDH locus, D. ochroleuca and D. incarnata in the places of their joint growth, differ in the allelic structure of the PGI and NADHD loci. D. incarnata from the Urals and Siberia were polymorphic for both loci, and individuals from Belarus were polymorphic for one locus (PGI). In contrast, all D. ochroleuca individuals growing in sympatric populations with polymorphic D. incarnata were homozygous for the same alleles. Thus, comparison of the genetic structure of D. ochroleuca and D. incarnata points to the existence of a genetic isolation and a functioning isolation mechanism even under conditions of their joint growth. We found that the GDH locus in D. incarnata is polymorphic only in populations which grow together with D. ochroleuca, with exception a few examples. Thus, we conclude that variability of the GDH locus in D. incarnata is associated with hybridization with D. ochroleuca.  相似文献   

5.
In this study, we assessed geographic patterns of genetic variations in nuclear and chloroplast genomes of two related native oaks in Japan, Quercus aliena and Q. serrata, in order to facilitate development of genetic guidelines for transfer of planting stocks for each species. A total of 12 populations of Q. aliena and 44 populations of Q. serrata were analyzed in this study. Genotyping of nuclear microsatellites in Q. aliena was done with only nine populations (n = 212) due to limited numbers of individuals in two populations, while all 12 populations (n = 89) were used in sequencing chloroplast DNA (cpDNA). In Q. serrata, 43 populations (n = 1032) were genotyped by nuclear microsatellite markers, while cpDNA of 44 populations (n = 350) was sequenced. As anticipated, geographic patterns detected in the variations of Q. aliena’s nuclear genome and its chloroplast haplotype distribution clearly distinguished northern and southern groups of populations. However, those of Q. serrata were inconsistent. The geographic distribution of its chloroplast haplotypes tends to show the predicted differentiation between northern and southern lineages, but geographic signals in the genetic structure of its nuclear microsatellites are weak. Therefore, treating northern and southern regions of Japan as genetically distinct transferrable zones for planting stocks is highly warranted for Q. aliena. For Q. serrata, the strong NE-SW geographic structure of cpDNA should be considered.  相似文献   

6.
120 years ago G.G. Jacobson described two species of leaf beetles from the South Urals that have remained poorly studied until recently. Chrysolina roddi, previously known only from the foothills and low mountains of the South Urals, the low Zhiguli Mountains, and the limestone cliffs on the Don River, is recorded here for the first time from the alpine tundra of the Iremel massif; its host plant in the alpine zone is the small alpine lovage Pachypleurum simplex (= Ligusticum mutellinoides), family Apiaceae. Two species of the subgenus Crositops, Ch. roddi and Ch. kabaki, are presently treated as foothill-alpine disjunct taxa. The distribution of Ch. poretzkyi, described from the low-montane part of Bashkortostan, also shows a foothill-alpine disjunction. Alpine populations of Ch. poretzkyi are described here as a new subspecies Ch. (Arctolina) poretzkyi olschwangi Mikhailov subsp. n. Revision of the type of Ch. poretzkyi that has long been considered lost confirms that this species belongs to the subgenus Arctolina, in disagreement with its previous placement in the subgenus Pleurosticha. Within Arctolina, the identity of Ch. tundralis and its differences from Ch. poretzkyi are discussed.  相似文献   

7.
The objectives of conservation and sustainable forest management require in depth study of genomes of woody plants and definition of their intraspecific genetic diversity. In recent years, an approach was developed based on the study of “candidate genes” that can potentially be involved in the formation of adaptive traits. In this study, we investigated nucleotide polymorphism of several adaptive candidate genes in the populations of Siberian larch (Larix sibirica Ledeb.) in the Urals. Representatives of this genus are among the most valuable and widely distributed forest tree species in Russia. From ten selected gene loci in the genome of L. sibirica, we isolated and investigated three loci, one of which (ABA-WDS) was sequenced in L. sibirica for the first time. The total length of the analyzed sequence in each individual amounted to 2865 bp. The length of locus alignment was from 360 bp to 1395 bp. In total, we identified 200 polymorphic positions. The most conservative is locus 4CL1-363, and the most polymorphic is locus sSPcDFD040B03103-274. The studied populations of L. sibirica are characterized by a high level of nucleotide polymorphism in comparison with other species and genuses (Picea, Pinus, Pseudotsuga, Abies) conifers plants (Hd = 0.896; π = 0.007; θW = 0.015). The most selectively neutral polymorphism (D T =–0.997) was attributed to locus 4CL1-363, and polymorphism with high probability of adaptability (D T =–1.807) was determined for the ABA-WDS locus. We identified 54 SNP markers, only five of which were nonsynonymous (9.26%) replacements. The average frequency of SNPs in the three studied loci of L. sibirica was one SNP in 53 bp. We detected unique SNP markers for eight populations, which could potentially be used to identify populations. Populations that are characterized by the highest number of unique SNP markers can be recommended for selection in order to preserve the gene pool of the species.  相似文献   

8.
9.
A new species, Betula erkovetskiensis Blokhina et O.V. Bondarenko (Betulaceae), from the deposits of the Sazanka Formation (upper Middle?Upper Miocene) of the Erkovetskii Brown Coal Field (Amur Region, Russia) is described based on anatomical features of fossil wood. The new species shows some wood anatomical characters of the extant birch subgenus Betula, B. davurica, B. nigra (section Dahuricae), and B. papyrifera (section Betula). Fossil wood of Betula is found in the Amur Region for the first time.  相似文献   

10.
11.
An analysis of indicator values of four Saussurea DC. species, S. baicalensis (Adams) B. L. Rob., S. frolowii Ledeb., S. salicifolia (L.) DC., and S. schanginiana (Wydl.) Fisch. ex Serg., have been carried out by the method of indicator scales of soil moisture and nutrient availability and salinity in more than 1600 relevés. The size of their ecological ranges and the values of their competitiveness in phytocenoses are determined. As a result of a comparison of the locality of local populations within the ecological range and their occurrence, the vulnerability of S. baicalensis, S. frolowii, S. salicifolia, and S. schanginiana in the Kuznetsk Alatau is evaluated. The types of rarity for these species in the Kuznetsk Alatau are determined.  相似文献   

12.
Legume crops in Central India, the main soybean production area of the country, may suffer from yellow mosaic disease caused by the Mungbean yellow mosaic India virus (MYMIV). MYMIV is transmitted by the sweet potato whitefly, Bemisia tabaci (Gennadius), which is a species complex composed of various genetic groups. This vector species harbors different endosymbionts among regional strains and among individuals. To elucidate fundamental aspects of this virus vector in the state of Madhya Pradesh, the infection status of the symbionts and the virus in whiteflies was studied. A polymerase chain reaction (PCR) survey of the whiteflies collected in Madhya Pradesh found four secondary endosymbionts, Arsenophonus, Hemipteriphilus, Wolbachia, and Cardinium, in addition to the primary endosymbiont Portiera. Arsenophonus and Hemipteriphilus were highly infected but the infection rates of Wolbachia and Cardinium were low. MYMIV was detected in whitefly populations collected from various host plants in Madhya Pradesh. The whitefly populations belonged to the Asia I and II genetic groups; several different Asia II populations were also distributed. Specific relations were not observed among symbiont infection status, virus infection, and the whitefly genetic groups in the populations of Madhya Pradesh, though Cardinium was highly detected in the Asia II-1 group. New primers, which can be used for PCR template validation and for discriminating two phylogenetically close endosymbionts, were designed.  相似文献   

13.
A large number of Crassostrea oysters are found in Asia-Pacific. While analyses of interspecific variation have helped to establish historical relationships among these species, studies on intraspecific variation are necessary to understand their recent evolutionary history and current forces driving population biology. We resequenced 18 and analyzed 31 mitogenomes of five Crassostrea species from China: Crassostrea gigas, Crassostrea angulata, Crassostrea sikamea, Crassostrea ariakensis, and Crassostrea hongkongensis. Our analysis finds abundant insertions, deletions, and single-nucleotide polymorphisms in all species. Intraspecific variation varies greatly among species with polymorphic sites ranging from 54 to 293 and nucleotide diversity ranging from 0.00106 to 0.00683. In all measurements, C. hongkongensis that has the narrowest geographic distribution exhibits the least sequence diversity; C. ariakensis that has the widest distribution shows the highest diversity, and species with intermediate distribution show intermediate levels of diversity. Low sequence diversity in C. hongkongensis may reflect recent bottlenecks that are probably exacerbated by human transplantation. High diversity in C. ariakensis is likely due to divergence of northern and southern China populations that have been separated without gene flow. The significant differences in mitogenome diversity suggest that the five sister species of Crassostrea have experienced different evolutionary forces since their divergence. The recent divergence of two C. ariakensis populations and the C. gigas/angulata species complex provides evidence for continued diversification and speciation of Crassostrea species along China’s coast, which are shaped by unknown mechanisms in a north–south divide.  相似文献   

14.
Do trade-offs between growth and reproduction differ between an invasive and noninvasive plant species and how do such trade-offs relate to population demographics? To help address these questions, we compared demographics for an invasive plant species, Rubus discolor, with a noninvasive congener, R. ursinus, in several populations of varying density. Removal of floral buds from reproductive canes increased the size of juvenile canes that arose from clonal sprouting in R. ursinus, suggesting a trade-off between current reproduction and growth. Removal of floral buds had no effect on growth of R. discolor. R. ursinus displayed trade-offs between reproduction (sexual and vegetative) and future growth based on negative correlations between leaf area production and both clonal sprouting and seedling production during the previous year. R. discolor did not exhibit these trade-offs. Both species had high population growth rates in low-density populations, but exhibited little or no growth in high-density populations. A life table response experiment was used to determine the underlying cause for the effect of density on population growth. For R. ursinus, lack of population growth in high-density populations was due primarily to increased mortality of clonally sprouting canes, while for R. discolor, it was due to decreased clonal cane production. Elasticity analysis revealed that clonal growth was more important than sexual reproduction for population growth of both species. However, elasticity values for sexual reproduction in R. discolor were greater in high- than low-density populations. This suggests an increased reliance on sexual reproduction in populations that had reached stable sizes, which could increase the capacity of R. discolor to disperse to new sites. Elasticity analyses were also used to simulate the efficacy of various control strategies for R. discolor. Control of this species could be attained by reducing clonal production within existing populations while reducing seed production to limit establishment of new populations.  相似文献   

15.
Prunus yedoensis Matsumura is one of the popular ornamental flowering cherry trees native to northeastern Asia, and its wild populations have only been found on Jeju Island, Korea. Previous studies suggested that wild P. yedoensis (P. yedoensis var. nudiflora) is a hybrid species; however, there is no solid evidence on its exact parental origin and genomic organization. In this study, we developed a total of 38 nuclear gene-based DNA markers that can be universally amplifiable in the Prunus species using 586 Prunus Conserved Orthologous Gene Set (Prunus COS). Using the Prunus COS markers, we investigated the genetic structure of wild P. yedoensis populations and evaluated the putative parental species of wild P. yedoensis. Population structure and phylogenetic analysis of 73 wild P. yedoensis accessions and 54 accessions of other Prunus species revealed that the wild P. yedoensis on Jeju Island is a natural homoploid hybrid. Sequence-level comparison of Prunus COS markers between species suggested that wild P. yedoensis might originate from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura. Moreover, approximately 81% of the wild P. yedoensis accessions examined were likely F1 hybrids, whereas the remaining 19% were backcross hybrids resulting from additional asymmetric introgression of parental genotypes. These findings suggest that complex hybridization of the Prunus species on Jeju Island can produce a range of variable hybrid offspring. Overall, this study makes a significant contribution to address issues of the origin, nomenclature, and genetic relationship of ornamental P. yedoensis.  相似文献   

16.
Bruguiera hainesii (Rhizophoraceae) is one of the two Critically Endangered mangrove species listed in the IUCN Red List of Threatened Species. Although the species is vulnerable to extinction, its genetic diversity and the evolutionary relationships with other Bruguiera species are not well understood. Also, intermediate morphological characters imply that the species might be of hybrid origin. To clarify the genetic relationship between B. hainesii and other Bruguiera species, we conducted molecular analyses including all six Bruguiera species using DNA sequences of two nuclear genes (CesA and UNK) and three chloroplast regions (intergenic spacer regions of trnL-trnF, trnS-trnG and atpB-rbcL). For nuclear DNA markers, all nine B. hainesii samples from five populations were heterozygous at both loci, with one allele was shared with B. cylindrica, and the other with B. gymnorhiza. For chloroplast DNA markers, the two haplotypes found in B. hainesii were shared only by B. cylindrica. These results suggested that B. hainesii is a hybrid between B. cylindrica as the maternal parent and B. gymnorhiza as the paternal one. Furthermore, chloroplast DNA haplotypes found in B. hainesii suggest that hybridization has occurred independently in regions where the distribution ranges of the parental species meet. As the IUCN Red List of Threatened Species currently excludes hybrids (except for apomictic plant hybrids), the conservation status of B. hainesii should be reconsidered.  相似文献   

17.
Three Azorean endemic Ammi species were initially described: Ammi trifoliatum (Wats.) Trel., Ammi seubertianum (Wats.) Trel. and Ammi huntii (Wats.) Trel. Many taxonomic changes have been conducted, and one to three species have been considered. Two species are currently accepted: A. trifoliatum, which occurs in almost every island, and A. seubertianum, with a narrower distribution. In this research, the population genetic diversity and structure of the Azorean Ammi species were assessed using eight specifically designed SSR markers. A wide sampling of A. seubertianum and A. trifoliatum was conducted in seven Azorean islands, and four A. huntii herbarium samples were also included to further contribute to the taxonomy of this genus in Azores. Flores populations showed the highest genetic diversity, while North of Topo, in São Jorge, showed the lowest. None of the populations analysed displayed signs of putative inbreeding. The population genetic structure analyses conducted partially provided support for the two currently accepted species, but other possible cryptic taxa may also be present. The complex clustering obtained seems to result from a combined action of geography, geology and ecology, and although island-specific genetic patterns were found, environmental conditions connected to different altitudes and the existence of micro-niches may also play an important role. A thorough morphological revision and ecophysiological studies should be conducted to clarify the number of endemic taxonomic entities present in the Azores archipelago.  相似文献   

18.
During the first half of the twentieth century, two accidental cases of introduction of Pissodes weevils were recorded from the southern hemisphere. The weevils in South Africa were identified as the deodar weevil (Pissodes nemorensis) and those in South America as the small banded pine weevil (Pissodes castaneus). Wide distribution of the two species in their invasive range, general difficulty in identifying some Pissodes spp., and the varying feeding and breeding behaviours of the species in South Africa has necessitated better evidence of species identity and genetic diversity of both species and population structure of the species in South Africa. Barcoding and the Jerry-to-Pat region of the COI gene were investigated. Morphometric data of the South African species was analysed. Our results confirmed the introduction of only one Pissodes species of North American origin to South Africa. However, this species is not P. nemorensis, but an unrecognized species of the P. strobi complex or a hybrid between P. strobi and P. nemorensis. Only P. castaneus, of European origin, was identified from South America. We identified ten mitochondrial DNA haplotypes from South Africa with evidence of moderate genetic structure among geographic populations. Terminal leader and bole-feeding weevils did not differ at the COI locus. A single haplotype was identified from populations of P. castaneus in South America. Results of the present study will have implications on quarantine, research and management of these insect species.  相似文献   

19.
Ficus (Moraceae) is a keystone group in tropical and subtropical forests with remarkable diversity of species and taxonomical challenges as a consequence of fig–pollinator coevolution. Ficus subsect. Frutescentiae includes about 30 species that are predominantly shrubs or small trees with Terminalia branching. Many of these species are difficult to delimit morphologically, and the group includes a tangle of uncertain taxa and incorrectly applied names. We conducted a phylogenetic analysis with internal and external transcribed spacer data (ITS and ETS) and data from 18 polymorphic microsatellite loci to evaluate the species status of the most perplexing members of this subsection. The results confirm the monophyly of subsect. Frutescentiae, with F. pedunculosa as sister to the rest. The F. erecta complex comprises approximately 17 taxa: F. erecta, F. abelii, F. boninsimae, F. nishimurae, F. iidaiana, F. gasparriniana var. laceratifolia, F. gasparriniana var. viridescens, F. pyriformis, F. stenophylla, F. fusuiensis, F. fengkaiensis, F. sinociliata, F. tannoensis, F. vaccinioides, F. formosana, F. pandurata, and F. periptera. The last five of these were supported as good species, while the others were not well supported by the present evidence. Evidence also supported the status of the non-F. erecta complex species including. F. pedunculosa, F. ischnopoda, F. heteromorpha, and F. variolosa. Ficus filicauda and F. neriifolia are possibly conspecific. The species status of F. potingensis should be restored and it should be treated as a member of section Eriosycea. Identification of the remaining taxa (F. gasparriniana var. esquirolii, F. ruyuanensis, F. daimingshanensis, F. chapaensis, F. changii, F. trivia, and F. tuphapensis) and their relationships to the F. erecta complex were not clarified. As a whole, only ten species in this subsection are confirmed, one is excluded, one is synonymous, and the others are either unresolved or short of samples. There appears to be a consistent genetic background among these unresolved groups, which suggests that repeated hybridization (as a result of pollinator host shifts) has filled up the interspecific gaps during the fig–pollinator coevolution process.  相似文献   

20.
In connection with the problems of identification of certain species of the genus Ponticola, and especially their juveniles, morphological and genetic studies of gobies collected in the northwestern part of the Black Sea basin were carried out using literature data and museum collections. Karyological data indicate a distinct species status of western (P. odessicus) and eastern (P. eurycephalus) mushroom gobies; the range of the latter includes not only the Sea of Azov but also waters of the Black Sea coast of the Crimean Peninsula; these conclusions are supported by preliminary molecular genetic studies. Based on the obtained results of intraspecific morphological variability of species, we propose morphological characteristics for identification of adult P. syrman and P. odessicus, as well as a specific set of characteristics to identify juvenile (body length less than 50 mm) P. syrman, P. kessleri, and P. odessicus. We reveal differences in the karyotype structure of P. syrman from populations of the Sasyk Lake and the Don River, which do not differ in terms of external morphological characteristics and variability of cytochrome b haplotypes. The need for further research of phylogeography and morphological and karyological variability of P. syrman sensu lato is assumed.  相似文献   

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