rDNA site number polymorphism and NOR inactivation in natural populations ofAllium schoenoprasum

Genetica ◽  
1994 ◽  
Vol 94 (1) ◽  
pp. 67-71 ◽  
Author(s):  
M. A. Garrido ◽  
M. Jamilena ◽  
R. Lozano ◽  
C. Ruiz Rejon ◽  
M. Ruiz Rejon ◽  
...  
Keyword(s):  
Natural Populations ◽  
Rdna Site ◽  
Site Number

scholarly journals High and uneven levels of 45S rDNA site-number variation across wild populations of a diploid plant genus (Anacyclus, Asteraceae)

PLoS ONE ◽  
2017 ◽  
Vol 12 (10) ◽  
pp. e0187131 ◽  
Author(s):  
Marcela Rosato ◽  
Inés Álvarez ◽  
Gonzalo Nieto Feliner ◽  
Josep A. Rosselló
Keyword(s):  
Rdna Site ◽  
45S Rdna ◽  
Wild Populations ◽  
Diploid Plant ◽  
Site Number ◽  
Number Variation

scholarly journals Temporal frames of 45S rDNA site-number variation in diploid plant lineages: lessons from the rock rose genusCistus(Cistaceae)

2016 ◽  
Author(s):  
Chiara Totta ◽  
Marcela Rosato ◽  
Pablo Ferrer-Gallego ◽  
Fernando Lucchese ◽  
Josep A. Rosselló
Keyword(s):  
Rdna Site ◽  
45S Rdna ◽  
Diploid Plant ◽  
Site Number ◽  
Number Variation

High-voltage electron microscopy of maxillary gland of spirochete-infected brine shrimp: lesion of efferent tubule

1988 ◽  
Vol 46 ◽  
pp. 362-363
Author(s):  
G. E. Tyson ◽  
M. J. Song
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Brine Shrimp ◽  
Natural Populations ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Infected Adult

Natural populations of the brine shrimp, Artemia, may possess spirochete- infected animals in low numbers. The ultrastructure of Artemia's spirochete has been described by conventional transmission electron microscopy. In infected shrimp, spirochetal cells were abundant in the blood and also occurred intra- and extracellularly in the three organs examined, i.e. the maxillary gland (segmental excretory organ), the integument, and certain muscles The efferent-tubule region of the maxillary gland possessed a distinctive lesion comprised of a group of spirochetes, together with numerous small vesicles, situated in a cave-like indentation of the base of the tubule epithelium. in some instances the basal lamina at a lesion site was clearly discontinuous. High-voltage electron microscopy has now been used to study lesions of the efferent tubule, with the aim of understanding better their three-dimensional structure.Tissue from one maxillary gland of an infected, adult, female brine shrimp was used for HVEM study.

Effect of acid deposition on trichome morphology and dogwood anthracnose biology

1992 ◽  
Vol 50 (1) ◽  
pp. 840-841
Author(s):  
Kyle T. Thornham ◽  
R. Jay Stipes ◽  
Randolph L. Grayson
Keyword(s):  
Acid Deposition ◽  
Disease Incidence ◽  
Natural Populations ◽  
Tree Disease ◽  
Flowering Dogwood ◽  
Discula Destructiva ◽  
Disease Induction ◽  
Dogwood Anthracnose ◽  
Trichome Morphology ◽  
Precipitation Events

Dogwood anthracnose, caused by Discula destructiva (1), is another new catastrophic tree disease that has ravaged natural populations of the flowering dogwood (Cornus florida) in the Appalachians over the past 15 years, and the epidemic is prognosticated to continue (2). An estimated 9.5 million acres have been affected, primarily in the Appalachian Mountains, from VA southwards, alone, and an estimated 50% of all dogwoods in PA have been killed. Since acid deposition has been linked experimentally with disease induction, and since the disease incidence and severity are more pronounced at higher elevations where lower pH precipitation events occur, we investigated the effect of acidic foliar sprays on moiphologic changes in the foliar cuticle and trichomes (3), the initial sites of infection and foci of Discula sporulation.

Comparative analysis of polyphenols and flavonoids in natural populations of Crataegus monogyna from Eastern Carpathians

Planta Medica ◽  
2011 ◽  
Vol 77 (12) ◽  
Author(s):  
ET Toth ◽  
G Mitroi ◽  
L Kelemen ◽  
MC Ichim
Keyword(s):  
Comparative Analysis ◽  
Natural Populations ◽  
Crataegus Monogyna ◽  
Eastern Carpathians

VARIABILITY OF MORPHOLOGICAL TRAITS OF SALVIA BECKERI (LAMIACEAE) IN NATURAL POPULATIONS OF DAGESTAN

2019 ◽  
Vol 5 (4) ◽  
pp. 36-46
Author(s):  
Z.A. Guseynova ◽  
◽  
R.A. Murtazaliev ◽  
Keyword(s):  
Morphological Traits ◽  
Natural Populations

STUDY OF THE TOTAL CONTENT OF SOME PHENOLIC COMPOUNDS IN OVERGROUND PARTS OF SALVIA TESQUICOLA KLOK.ET POBED. IN NATURAL POPULATIONS OF DAGESTAN

2019 ◽  
Vol 5 (4) ◽  
pp. 20-28
Author(s):  
F.A. Vagabova ◽  
◽  
G.K. Radzhabov ◽  
F.I. Islamova ◽  
A.N. Alibegova ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Natural Populations ◽  
Total Content

Urbanization of fauna on the example of marsh frog (Pelophylax ridibundus)

2015 ◽  
Vol 26 (3-4) ◽  
pp. 116-123
Author(s):  
A. P. Korzh ◽  
T. V. Zahovalko
Keyword(s):  
Urban Areas ◽  
Cognitive Modeling ◽  
Negative Impact ◽  
Natural Populations ◽  
Cellular Level ◽  
Anthropogenic Factors ◽  
Migration Routes ◽  
Corrective Effect ◽  
The Impact ◽  
The City

Recently, the number of published works devoted to the processes of synanthropization of fauna, is growing like an avalanche, which indicates the extreme urgency of this theme. In our view, the process of forming devices to coexist with human and the results of his life reflects the general tandency of the modern nature evolution. Urbanization is characteristic for such a specific group of animals like amphibians, the evidence of which are numerous literature data. Many researchers use this group to assess the bioindicative quality of the environment. For this aim a variety of indicators are used: from the cellular level of life of organization up to the species composition of the group in different territories. At the same time, the interpretation of the results is not always comparable for different areas and often have significantly different interpretations by experts. Urban environment, primarily due to the contamination is extremely aggressive to amphibians. As a consequence, the urban populations of amphibians may be a change in the demographic structure, affecting the reproductive ability of the population, the disappearance of the most sensitive species or individuals, resizing animals, the appearance of abnormalities in the development, etc. At the same time play an important amphibians in the ecosystems of cities, and some species in these conditions even feel relatively comfortable. Therefore, it is interesting to understand the mechanisms of self-sustaining populations of amphibians in urban environments. To assess the impact of natural and anthropogenic factors on the development of amphibian populations were used cognitive modeling using the program Vensim PLE. Cognitive map of the model for urban and suburban habitat conditions were the same. The differences concerned the strength of connections between individual factors (migration, fertility, pollution) and their orientation. In general, factors like pollution, parasites, predators had negative impact on the population, reducing its number. The birth rate, food and migration contributed to raising number of individuals. Some of the factors affected on the strength to of each other as well: the majority of the factors affected the structure of the population, had an influence on the fertility. Thanks to it the model reflects the additive effect of complex of factors on the subsequent status of the population. Proposed and analyzed four scenarios differing strength and duration of exposure. In the first scenario, a one-time contamination occurs and not subsequently repeated. The second and third scenario assumes half board contamination, 1 year (2 scenario) and two years (scenario 3). In the fourth scenario, the pollution affected the population of amphibians constantly. In accordance with the results of simulation, much weaker than the natural populations respond to pollution - have them as an intensive population growth and its disappearance at constant pollution is slow. Changes to other parameters of the model showed that this pollution is the decisive factor -only the constant action leads to a lethal outcome for the populations. All other components of the model have a corrective effect on the population dynamics, without changing its underlying trand. In urban areas due to the heavy impact of pollution maintaining the population is only possible thanks to the migration process – the constant replenishment of diminishing micropopulations of natural reserves. This confirms the assumption that the form of existence metapopulations lake frog in the city. In order to maintain the number of amphibians in urban areas at a high level it is necessary to maintain existing migration routes and the creation of new ones. Insular nature of the placement of suitable habitats in urban areas causes the metapopulation structure of the types of urbanists. Therefore, the process of urbanization is much easier for those species whicht are capable of migration in conditions of city. In the initial stages of settling the city micropopulationis formed by selective mortality of the most susceptible individuals to adverse effects. In future, maintaining the categories of individuals is provided mainly due to migration processes metapopulisation form of the species of existence is supported). It should be noted that the changes in the previous levels are always saved in future. In the case of reorganizations of individuals we of morphology can assume the existence of extremely adverse environmental conditions that threaten the extinction of the micropopulations. 

Species composition and distribution of marine macro algae at Co To and Thanh Lan archipelago

2020 ◽  
Vol 20 (3) ◽  
pp. 267-276
Author(s):  
Dam Duc Tien ◽  
Nguyen Thi Mai Anh ◽  
Linh Manh Nguyen ◽  
Pham Thu Hue ◽  
Lawrence Liao
Keyword(s):  
Species Composition ◽  
Littoral Zone ◽  
Marine Algae ◽  
Similarity Coefficient ◽  
Algal Flora ◽  
Average Value ◽  
Site Number ◽  
Species Composition And Distribution ◽  
Total Species ◽  
Macro Algae

This paper exhibites species composition and distribution of marine seaweed at 10 sites of Co To and Thanh Lan islands in May 2019. The studies record 76 species of marine algae in the area, belonging to four divisions: Cyanophytes, Rhodophytes, Ochrophytes and Chlorophytes. Among them, five species are classified into Cyanophytes (comprising 6.6% of total species); thirty-four species into Rhodophytes (44.7%); twenty-one species into Ochrophytes/Phaeophytes (27.6%) and sixteen species into Chlorophytes (21.1%). The species composition of marine seaweeds in Co To and Thanh Lan shows significant differences as follows: 22 species (sites number 4 and 10) to 58 species (site number 2) and the average value is 38.7 species per site. Sørensen similarity coefficient fluctuates from 0.33 (sites number 5 and 10) to 0.84 (sites number 1 and 3) and the average value is 0.53. The current investigations show that four species of twenty-one species are collected in the littoral zone and forty-two species in the sub-littoral zone (in which there are thirteen species distributed in both littoral zone and sub-littoral zone). The algal flora in Co To and Thanh Lan is characterized by subtropics.

Dwindling status of Epimedium Elatum (Morren & Decne) and its geographical distribution in Kashmir Himalaya, India

2018 ◽  
pp. 47-52
Keyword(s):  
Medicinal Plant ◽  
Biological Activities ◽  
Conservation Status ◽  
Natural Populations ◽  
Culture Techniques ◽  
Kashmir Himalayas ◽  
Near Future ◽  
First Time ◽  
Tissue Culture Techniques

Epimedium elatum (Morren & Decne) of family Berberidaceace is a rare perennial medicinal plant, endemic to high altitude forests of Northwestern Himalayas in India. Ethnobotanically, it has been used as an ingredient for treatment of bone-joint disorders, impotence and kidney disorders in Kashmir Himalayas. Phytochemically, it is rich in Epimedin ABC and Icariin; all of these have been demonstrated to possess remarkable biological activities like PDE-5 inhibition (treatment of erectile dysfunction), anticancer, antiosteoporosis antioxidant and antiviral properties. The present investigation reports its traditional usage, comprehensive distribution and conservation status from twenty ecogeographical regions in Kashmir Himalayas, India. The species was reported from Gurez valley for the first time. Numerous threats like excessive grazing, deforestration, habitat fragmentation, tourism encroachment, landslides and excessive exploitation have decreased its natural populations in most of the surveyed habitats. Consequently, its existence may become threatened in near future if timely conservation steps are not taken immediately by concerned stakeholders involved in medicinal plant research. Moreover, use of plant tissue culture techniques is recommended for development of its in vitro propagation protocols. Therefore, introduction of this medicinal plant in botanical gardens, protected sites and development of monitoring programmes are needed for its immediate conservation in Northwestern Himalayas, India.

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