scholarly journals Cultivated poplars (Populus, Salicaceae) of Saratov and Engels (Saratov province)

2018 ◽  
pp. 33-42 ◽  
Author(s):  
M.V. Kostina ◽  
Yu.A. Nasimovich
Keyword(s):  
Taxonomic Composition ◽  
The South ◽  
Pure Species ◽  
Northern Cities ◽  
Local Species ◽  
Distinguished Varieties ◽  
Species Hybrids

The aim of the study was to find out taxonomic composition of poplars cultivated to the south of Moscow, which is poorly known compared to big northern cities like Moscow or St. Petersburg. Species, hybrids and cultivars were identified by morphology. In Saratov and Engels we found two local species of Populus (P. alba, P. nigra), 1 alien (P. simonii) and about 10 hybrids, mostly cultivars. P. nigra is represented by two well distinguished varieties. Hybrids, especially the complex ones (P. x petrovskoe) are predominant over “pure” species. The composition of ornamental poplars in these towns is approximately similar to Moscow, differences are due to a more southern location, smaller size of the towns , and their position inside the P. nigra and outside the P. longifolia areas.

scholarly journals NEW REVIEW OF POACEAE OF THE MIDDLE VOLGA REGION

Ekosistemy ◽  
2020 ◽  
pp. 43-62
Author(s):  
S. V. Saksonov ◽  
V. M. Vasjukov ◽  
S. A. Senator
Keyword(s):  
Higher Plants ◽  
Taxonomic Composition ◽  
Volga Region ◽  
The South ◽  
Middle Volga Region ◽  
Psathyrostachys Juncea ◽  
Nardus Stricta ◽  
Ulyanovsk Region ◽  
Middle Volga ◽  
Herbarium Collections

Grasses one of the largest families of higher plants, including about 12000 species from 950 genera. The paper presents up-to-date information about the taxonomic composition, geographical distribution and habitat conditions of cereals in the South of the Middle Volga region (within the Penza, Samara and Ulyanovsk regions). studies of Grasses were conducted throughout the southern Middle Volga region, and herbarium collections stored in LE, MOSP, MW, PKM, PVB, etc. were also studied. Agrostology the South of the Middle Volga region are 72 genera (including 2 nothogenera) and 221 species (including 5 nothospecies). In the flora of the Southern Middle Volga region, 20 rare species of Grasses, of which 5 species are included in the Red book of the Russian Federation (2008): Koeleria sclerophylla, Stipa dasyphylla, S. pennata, S. pulcherrima, S. zalesskii; 14 species – in the Red book of the Penza region (2013): Drymochloa sylvatica, Festuca wolgensis, Helictotrichon desertorum, Melica transsilvanica, Scolochloa festucacea, Stipa borysthenica, S. dasyphylla, S. lessingiana, S. pennata, S. pulcherrima, S. sareptana, S. tirsa, S. zalesskii, Trisetum sibiricum; 18 species – in the Red book of the Samara region (2017): Avenula pubescens, Bromopsis benekenii, Catabrosella humilis, Cinna latifolia, Cleistogenes squarrosa, Drymochloa sylvatica, Elytrigia pruinifera, Helictotrichon schellianum, Koeleria sclerophylla, Pholiurus pannonicus, Poa saksonovii, Psathyrostachys juncea, Stipa dasyphylla, S. korshinskyi, S. pennata, S. pulcherrima, S. tirsa, S. zalesskii; 18 species – in the Red book of the Ulyanovsk region (2015): Catabrosella humilis, Cleistogenes squarrosa, Drymochloa sylvatica, Festuca cretacea, F. wolgensis, Helictotrichon desertorum, Koeleria sclerophylla, Leymus ramosus, Nardus stricta, Psathyrostachys juncea, Stipa borysthenica, S. dasyphylla, S. korshinskyi, S. lessingiana, S. pennata, S. pulcherrima, S. tirsa, S. zalesskii. Only Poa saksonovii is endemic to the South of the Middle Volga region; 5 types of Grasses are described from the study area: Festuca wolgensis, Koeleria sclerophylla, K. transvolgensis, Leymus paboanus, Poa saksonovii.

Black Migration from the South in Historical Context

2016 ◽  
Author(s):  
Leah Platt Boustan
Keyword(s):  
World War I ◽  
Labor Demand ◽  
Economic Returns ◽  
Birth Cohorts ◽  
The South ◽  
Black Migration ◽  
The North ◽  
War Effort ◽  
Northern Cities ◽  
European Immigration

This chapter explains that the mobility of black southerners began increasing in the birth cohorts born immediately after the Civil War. Many of these moves took place within the South. Despite plentiful industrial jobs in the “thousand furnaces” of northern cities at the turn of the twentieth century, the potential wage benefits of settling in the North was dampened by the absence of a migrant network that southern blacks could use to secure employment upon arrival. Large flows of northward migration awaited a period of abnormally high economic returns, which arose during World War I. Circa 1915, northern factories supplying the war effort experienced a surge in labor demand, coupled with a temporary freeze in European immigration, which encouraged northern employers to turn to other sources of labor.

scholarly journals Gene Flow Between Introduced and Native Eucalyptus Species: Morphological Analysis of Tri-Species and Backcross Hybrids Involving E. nitens

2007 ◽  
Vol 56 (1-6) ◽  
pp. 127-133 ◽  
Author(s):  
C. Barbour ◽  
B. M. Potts ◽  
R. E. Vaillancourt
Keyword(s):  
Gene Flow ◽  
Second Generation ◽  
Current Work ◽  
F1 Hybrids ◽  
Morphological Identification ◽  
Eucalyptus Species ◽  
Pure Species ◽  
Backcross Hybrids ◽  
In The Wild ◽  
Species Hybrids

Summary Morphometric analyses were conducted on second-generation tri-species and backcross hybrids in Eucalyptus. These hybrids were all produced using pollen from two E. nitens x cordata F1 hybrids and controlled pollination techniques. Tri-species hybrids were created with E. gunnii, E. ovata and E. viminalis as females, while backcrosses were produced with E. cordata. Multivariate analysis of seedling characteristics indicated that eighty percent of the backcross hybrids fell within the morphological range of E. cordata. All three cross combinations of the tri-species hybrids were biased away from E. nitens and towards their maternal parent and E. cordata. The inclusion of data for first-generation (F1) hybrids between the pure parental species in the current work showed the F1’s to be easily distinguishable from pure species, compared to second-generation hybrids. The use of morphology for detecting second-generation hybridisation involving exotic plantation species and native eucalypt populations will therefore be unreliable, and identifies a need for preventing second-generation hybrids from establish in the wild. The current work, nevertheless, provides further demonstration of the effectiveness of morphological identification of F1 hybrids. The easy recognition of F1 hybrids will be useful in identifying sites and species at risk of exotic gene flow and enable the development of weeding programs that focus on removing exotic hybrids in the wild.

Patterns of Inheritance in the Bowing Display and Associated Behaviour of Some Hybrid Streptopelia Doves

Behaviour ◽  
1970 ◽  
Vol 36 (3) ◽  
pp. 187-214 ◽  
Author(s):  
S.J.J.F. Davies
Keyword(s):  
The Other ◽  
F1 Hybrids ◽  
Characteristic Form ◽  
Pure Species ◽  
F1 Hybrid ◽  
Cine Film ◽  
F2 Generation ◽  
Species Hybrids ◽  
Relative Variability

AbstractThe bowing display of Streptopelia doves was studied in captive individuals of five species at Madingley, Cambridge, England from 1961 to 1964. The five species were S. roseogrisea-(risoria) (barbary), S. decaocto (collared), S. turtur (turtle), S. chinensis (necklace) and S. senegalensis (senegal). F1 hybrids were bred between the barbary and the other four species and single males of each of the F1 necklace x collared and senegal x turtle were also observed. F2 generation birds of the collared x barbary F1 hybrid, as well as some backcrossed birds were included in the study. Bowing displays were usually given only by male doves when close to another dove. The form of the bowing display differed from species to species and exhibited a typical intensity in each species. Each hybrid also had a bowing display of characteristic form. The ciné film showed that there was variation in form between the bowing cycles of any one bout, both in the pure species and in the hybrids. This variation could not be adequately described from the films taken in this study. The rate of bowing of each species was constant and differed from that of every other species. Hybrids also exhibited a typical intensity in this character. There was much more intra-specific and intra-hybrid variaton in the timing of individual movements within bowing cycles in a bout than in the timing of the bowing cycle as a whole. The relative variability of the different elements could be ranked, and in all species and hybrids studied the timing of the total cycle tended to be least variable and that of the pause at the top of the bow most variable. The frequencies with which bowing displays and kah calls were given under standard conditions, were measured, and provided two other behavioural characters whose pattern of inheritance could be studied. Three patterns of inheritance were found in each of these behaviour patterns of the F1 hybrids. In some cases the behaviour was intermediate between that of the two parents, in others it approximated the behaviour of one parent closely and in others again the hybrid's behaviour exceeded the range of either parent.

scholarly journals Patterns of evolution of genes disrupted in expression in Drosophila species hybrids

2005 ◽  
Vol 85 (2) ◽  
pp. 119-125 ◽  
Author(s):  
MOHAMED A. F. NOOR
Keyword(s):  
Amino Acid ◽  
Parental Species ◽  
Species Group ◽  
Pure Species ◽  
X Chromosomes ◽  
Regulatory Pathways ◽  
Regulatory Architecture ◽  
Species Groups ◽  
Male Specific ◽  
Species Hybrids

Divergence between species in regulatory pathways may contribute to hybrid incompatibilities such as sterility. Consistent with this idea, genes involved in male fertility often evolve faster than most other genes both in amino acid sequence and in expression. Previously, we identified a panel of male-specific genes underexpressed in sterile male hybrids of Drosophila simulans and D. mauritiana relative to pure species, and we showed that this underexpression is associated with infertility. In a preliminary effort to assess the generalities in the patterns of evolution of these genes, I examined patterns of mRNA expression in three of these genes in sterile F1 hybrid males of D. pseudoobscura and D. persimilis. F1 hybrid males bearing D. persimilis X chromosomes underexpressed all these genes relative to the parental species, while hybrids bearing D. pseudoobscura X chromosomes underexpressed two of these three genes. Interestingly, the third gene, CG5762, has undergone extensive amino acid evolution within the D. pseudoobscura species group, possibly driven by positive natural selection. We conclude that some of the same genes exhibit disruptions in expression within each of the two species groups, which could suggest commonalities in the regulatory architecture of sterility in these groups. Alternative explanations are also considered.

scholarly journals The taxonomic structure of the fauna of ground beetles (Coleoptera, Carabidae) in the south of Eastern Siberia and Northern Mongolia

2021 ◽  
Vol 908 (1) ◽  
pp. 012022
Author(s):  
L Ts Khobrakova
Keyword(s):  
Ground Beetles ◽  
Taxonomic Composition ◽  
Taxonomic Structure ◽  
Eastern Siberia ◽  
The South ◽  
Study Region ◽  
Worldwide Distribution ◽  
Northern Mongolia ◽  
The World ◽  
Total Fauna

Abstract The taxonomic composition of the fauna has 577 species (608 subspecies) from 76 genera, representing 1% of the total fauna of the world and 5% of the Palearctic fauna. Most genera of ground beetles in the region have a predominantly Holarctic distribution, less often – Palearctic, tropical, or worldwide distribution. The fauna of the ground beetles of the region is based on the genera Amara, Bembidion, Pterostichus, Harpalus, and Carabus. The following genera are important for the fauna of ground beetles in the study region: Dyschirius, Agonum, Nebria, Cymindis, Dicheirotrichus, Poecilus, Trechus, Notiophilus, Elaphrus, Cicindela, Cylindera, Pogonus, Chlaenius, Pseudotaphoxenus.

scholarly journals Metagenomic Characterization of the Viral Community of the South Scotia Ridge

2018 ◽  
Author(s):  
Qingwei Yang ◽  
Chen Gao ◽  
Jiang Yong ◽  
Ming Wang ◽  
Xinhao Zhou ◽  
...  
Keyword(s):  
Phylogenetic Analyses ◽  
Great Influence ◽  
Austral Summer ◽  
Taxonomic Composition ◽  
Marker Genes ◽  
The South ◽  
Scotia Ridge ◽  
Viral Communities ◽  
The Antarctic ◽  
South Scotia Ridge

Viruses are the most abundant biological entities in aquatic ecosystems and harbor an enormous genetic diversity. While their great influence on the marine ecosystems is widely acknowledged, current information about their diversity remains scarce. A viral metagenomic analysis of three water samples was conducted from sites on the South Scotia Ridge (SSR) near the Antarctic Peninsula, during the austral summer 2016. The taxonomic composition and diversity of the viral communities were investigated and a functional assessment of the sequences was determined. Phylotypic analysis showed that most viruses belonging to the order Caudovirales, especially the family Podoviridae (41.92-48.7%), similar to the viromes from the Pacific Ocean. Functional analysis revealed a relatively high frequency of phage-associated and metabolism genes. Phylogenetic analyses of phage TerL and Capsid_NCLDV (nucleocytoplasmic large DNA viruses) marker genes indicated that many sequences associated with Caudovirales and NCLDV were novel and distinct from known phage genomes. High Phaeocystis globosa virus virophage (Pgvv) signatures were found in SSR area and complete and partial Pgvv-like were obtained which may have an influence on host-virus interactions. Our study expands the existing knowledge of viral communities and their diversities from the Antarctic region and provides basic data for further exploring polar microbiomes.

scholarly journals La muscadine (Vitis rotundifolia michx) et sa culture aux Etats-Unis

OENO One ◽  
1978 ◽  
Vol 12 (1) ◽  
pp. 1 ◽  
Author(s):  
Alain Bouquet
Keyword(s):  
Vitis Vinifera ◽  
Genetic Improvement ◽  
The South ◽  
Pure Species ◽  
Great Resistance ◽  
Genetic Characteristics ◽  
Vitis Rotundifolia ◽  
Commercial Scale ◽  
Original Species

<p style="text-align: justify;">La Muscadine (<em>Vitis rotundifolia</em> Michx), dont la culture est limitée à quelques milliers d'hectares dans le Sud-Est des Etats-Unis, est certainement l'espèce du genre <em>Vitis</em> la plus originale, par ses caractéristiques morphologiques, anatomiques, biologiques et génétiques.</p><p style="text-align: justify;">C'est avec <em>Vitis vinifera</em>, la seule espèce pure de vigne qui soit cultivée à l'échelle commerciale pour ses fruits. Les principaux aspects de cette viticulture sont passés en revue.</p><p style="text-align: justify;">L'une des caractéristiques les plus intéressantes de la Muscadine est sa résistance élevée à de nombreux parasites qui justifie son utilisation actuelle dans les programmes d'amélioration génétique de la vigne en Europe et en Californie.</p><p style="text-align: justify;">+++</p><p style="text-align: justify;">The Muscadine (<em>Vitis rotundifolia</em> Michx), the cultivation of which is limited a few thousand acres in the South-East of the U.S.A., is certainly the most original species of the <em>Vitis</em> genus, for its morphological, anatomical, biological and genetic characteristics.</p><p style="text-align: justify;">Together with <em>Vitis vinifera</em>, it is the only pure species of vine cultivated on a commercial scale for its fruit. The main aspects of this viticulture are reviewed.</p><p style="text-align: justify;">One of the most interesting characteristics of the Muscadine is its great resistance to numerous parasites which justifies its present use in programmes for the genetic improvement of the vine in Europe and California.</p>

Black Migration, Northern Cities, and Labor Markets after 1970

2016 ◽  
Author(s):  
Leah Platt Boustan
Keyword(s):  
Market Competition ◽  
Black Workers ◽  
Skilled Workers ◽  
The South ◽  
Central Cities ◽  
Black Migration ◽  
Black And White ◽  
Northern Cities ◽  
Blacks And Whites ◽  
American Cities

This concluding chapter examines how the three trends at the heart of this book's story—black migration from the South, the earnings convergence between blacks and whites, and white departures from central cities—have evolved in recent decades. By 1970, black migration from the South slowed, though black and white earnings have not converged further in northern cities. Just as black migration to northern cities tapered off, a new migration of low-skilled workers from Latin America was getting underway. This new migration wave coincided with decreased demand for manufacturing workers in American cities as a result of technological change and globalization. Thus, in recent years, black workers in northern cities have faced new sources of labor market competition, compounded by falling demand for some low-skilled operative and clerical positions, leading wages to stagnate further.

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