scholarly journals Evolutionary trade–off between defence against grazing and competitive ability in a simple unicellular alga, Chlorella vulgaris

2004 ◽  
Vol 271 (1551) ◽  
pp. 1947-1953 ◽  
Author(s):  
Takehito Yoshida ◽  
Nelson G. Hairston ◽  
Stephen P. Ellner
Keyword(s):  
Chlorella Vulgaris ◽  
Competitive Ability ◽  
Unicellular Alga ◽  
Trade Off

Trade-Off between Interspecific Competitive Ability and Growth Rate in Bacteria

Ecology ◽  
1990 ◽  
Vol 71 (2) ◽  
pp. 645-650 ◽  
Author(s):  
Yasushi Kurihara ◽  
Shuichi Shikano ◽  
Masahiko Toda
Keyword(s):  
Growth Rate ◽  
Competitive Ability ◽  
Trade Off

Influence of Metal-Containing Nanoparticles on the Content of Photosynthetic Pigments of Unicellular Alga Chlorella vulgaris Baijer

2017 ◽  
Vol 13 ◽  
pp. 255-262 ◽  
Author(s):  
Yuri N. Morgalev ◽  
Alexander V. Kurovsky ◽  
Irina A. Gosteva ◽  
Tamara G. Morgaleva ◽  
Sergey Yu. Morgalev ◽  
...  
Keyword(s):  
Chlorella Vulgaris ◽  
Photosynthetic Pigments ◽  
Control Sample ◽  
Culture Solution ◽  
Dual Phase ◽  
Unicellular Alga ◽  
Concentration Effects ◽  
Non Linear ◽  
High Concentrations ◽  
Monotone Decrease

The research studies concentration effects and influence of nCeO2, nZnO, nNi and nPt on photosynthetic pigments in Chlorella v. B. in conditions of homeostated lab cultivation. It was shown that dependency of the content of chlorophylls and carotenoids in chlorella cells on concentrations of nCeO2, nZnO and nPt has non-linear dual-phase character. Growing concentrations of nNi in the culture solution caused monotone decrease of all photosynthetic pigments in chlorella cells. Adding 0.1 mg/L nZnO in the suspension caused a statistically significant increase of the chlorophyll a and b content (27.1 % and 64.2 % respectively) in comparison with the control sample. NPs Pt at 1 mg/L induced stimulating effect on chlorophylls a (17.4 % compared to the control) and b (23.6 % compared to the control) in chlorella cells. The number of carotenoids had a statistically significant decrease in chlorella cells by 25-70 % at high concentrations (1-10 mg/L) for all tested NPs.

Trade-off between parasitoid resistance and larval competitive ability in Drosophila melanogaster

Nature ◽  
10.1038/38483 ◽  
1997 ◽  
Vol 389 (6648) ◽  
pp. 278-280 ◽  
Author(s):  
A. R. Kraaijeveld ◽  
H. C. J. Godfray
Keyword(s):  
Drosophila Melanogaster ◽  
Competitive Ability ◽  
Trade Off

scholarly journals Motility in multicellular Chlamydomonas reinhardtii (Chlamydomonadales, Chlorophyceae)

2017 ◽  
Author(s):  
Margrethe Boyd ◽  
Fran Rosenzweig ◽  
Matthew Herron
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Radiant Energy ◽  
Culture Conditions ◽  
Wild Type ◽  
Unicellular Alga ◽  
Trade Off ◽  
Directional Movement ◽  
Volvocine Algae ◽  
History Of

AbstractThe advent of multicellularity was a watershed event in the history of life, yet the transition from unicellularity to multicellularity is not well understood. Multicellularity opens up opportunities for innovations in intercellular communication, cooperation, and specialization, which can provide selective advantages under certain ecological conditions. The unicellular alga Chlamydomonas reinhardtii has never had a multicellular ancestor yet it is closely related to the volvocine algae, a clade containing taxa that range from simple unicells to large, specialized multicellular colonies. Simple multicellular structures have been observed to evolve in C. reinhardtii in response to predation or to settling rate-based selection. Structures formed in response to predation consist of individual cells grouped within a shared transparent extracellular matrix. Evolved isolates form such structures obligately under culture conditions in which their wild type ancestors do not, indicating that newly-evolved multicellularity is heritable. C. reinhardtii is capable of photosynthesis, and possesses an eyespot and two flagella with which it moves towards or away from light in order to optimize input of radiant energy. Motility contributes to C. reinhardtii fitness because it allows cells or colonies to achieve this optimum. Utilizing phototaxis to assay motility, we determined that newly evolved multicellular strains do not exhibit significant directional movement, even though the flagellae of their constituent unicells are present and active. In C. reinhardtii the first steps towards multicellularity in response to predation appear to result in a trade-off between motility and differential survivorship, a trade-off that must overcome by further genetic change to ensure the long-term success of the new multicellular organism.

scholarly journals The genetic backburn: using rapid evolution to halt invasions

2016 ◽  
Vol 283 (1825) ◽  
pp. 20153037 ◽  
Author(s):  
Ben L. Phillips ◽  
Richard Shine ◽  
Reid Tingley
Keyword(s):  
Competitive Ability ◽  
Rapid Evolution ◽  
Dispersal Distance ◽  
Long Distance Dispersal ◽  
Long Distance ◽  
Trade Off ◽  
Effective Barrier ◽  
Range Core ◽  
The Impact ◽  
Powerful Strategy

The impact of an invasive species depends upon the extent of area across which it ultimately spreads. A powerful strategy for limiting impact, then, is to limit spread, and this can most easily be achieved by managing or reinforcing natural barriers to spread. Using a simulation model, we show that rapid evolutionary increases in dispersal can render permeable an otherwise effective barrier. On the other hand, we also show that, once the barrier is reached, and if it holds, resultant evolutionary decreases in dispersal rapidly make the barrier more effective. Finally, we sketch a strategy—the genetic backburn—in which low-dispersal individuals from the range core are translocated to the nearside of the barrier ahead of the oncoming invasion. We find that the genetic backburn—by preventing invasion front genotypes reaching the barrier, and hastening the evolutionary decrease in dispersal—can make barriers substantially more effective. In our simulations, the genetic backburn never reduced barrier strength, however, the improvement to barrier strength was negligible when there was substantial long-distance dispersal, or when there was no genetic variation for dispersal distance. The improvement in barrier strength also depended on the trade-off between dispersal and competitive ability, with a stronger trade-off conferring greater power to the genetic backburn.

Perte de compétitivité par adaptation au milieu physique: cas du Salix uva-ursi dans la toundra du Nouveau-Québec

1988 ◽  
Vol 66 (8) ◽  
pp. 1532-1538 ◽  
Author(s):  
Lucie Maillette ◽  
Luc Bélisle ◽  
Maurice K. Seguin
Keyword(s):  
Competitive Ability ◽  
Slow Growth ◽  
Temporal Variations ◽  
The Other ◽  
Apparent Contradiction ◽  
Trade Off ◽  
Physical Conditions ◽  
Alpine Species ◽  
Slow Growing ◽  
Harsh Conditions

Plant species of wind-exposed tundra sites are usually low lying and slow growing. Such a combination probably reduces competitive ability, perhaps to the point of limiting wind-tolerant species to sites with little or no competition, i.e., the most exposed sites, as if there were a trade-off between adaptation to physical conditions and competitive ability. That hypothesis was tested with Salix uva-ursi Pursh, an arctic–alpine species common on windy sites in northern Quebec. Salix uva-ursi increases in abundance with exposure to wind, contrary to other species, but tolerates, even "prefers", the physical conditions found in sheltered sites. These two observations support the idea that interspecific competition limits the distribution of S. uva-ursi. However, the vigour of S. uva-ursi (number and size of shoots) is greatest in the sheltered sites, where the other species are more numerous and vigourous. This apparent contradiction between distribution and vigour could find an explanation in the temporal variations in climate. Under favourable conditions, prostrate and slow growth would be a handicap to S. uva-ursi, compared with other species, whereas under harsh conditions, species sensitive to wind and cold would suffer more than S. uva-ursi. [Translated by the journal]

scholarly journals Trade-off shapes diversity in eco-evolutionary dynamics

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Farnoush Farahpour ◽  
Mohammadkarim Saeedghalati ◽  
Verena S Brauer ◽  
Daniel Hoffmann
Keyword(s):  
Competitive Ability ◽  
Evolutionary Dynamics ◽  
Evolutionary Model ◽  
Self Organization ◽  
Mixed System ◽  
Replication Rate ◽  
Trade Off ◽  
Natural Systems ◽  
Sharp Phase Transition ◽  
Trait Space

We introduce an Interaction- and Trade-off-based Eco-Evolutionary Model (ITEEM), in which species are competing in a well-mixed system, and their evolution in interaction trait space is subject to a life-history trade-off between replication rate and competitive ability. We demonstrate that the shape of the trade-off has a fundamental impact on eco-evolutionary dynamics, as it imposes four phases of diversity, including a sharp phase transition. Despite its minimalism, ITEEM produces a remarkable range of patterns of eco-evolutionary dynamics that are observed in experimental and natural systems. Most notably we find self-organization towards structured communities with high and sustained diversity, in which competing species form interaction cycles similar to rock-paper-scissors games.

Plant population dynamics

2007 ◽  
Author(s):  
Michael J. Crawley
Keyword(s):  
Population Dynamics ◽  
Competitive Ability ◽  
Plant Population ◽  
Plant Population Dynamics ◽  
Trade Off ◽  
Trade Offs ◽  
Generation Times ◽  
High Death ◽  
Body Sizes ◽  
Rapid Generation

Plants exhibit an extraordinary range of sizes and generation times, from single-celled algae with body sizes of the order of 5 mm and generation times of the order of 1 day, to massive forest trees more than 50 m tall that can live for over 1000 years. Diatoms and trees have the virtue of being easy to count, so it is natural to seek to model the dynamics of changes in numbers. On the other hand, many herbaceous perennials (like clonal herbs or turf-forming grasses) are difficult or impossible to count, and for these plants it is natural to model the dynamics of fluctuation in biomass or proportional space occupancy. The theory of plant population dynamics is linked to the rest of plant biology through a series of fundamental trade-offs, reflecting the fact that individual plants are constrained in what they can do. There are important trade-offs in reproduction because a plant could produce many small seeds or a few large seeds, but it is not an option to produce many large seeds. Other trade-offs involve investment decisions: for instance a plant can invest in growth or defence and this leads to a trade-off between competitive ability and palatability to herbivores. Alternatively, high growth rate in full sun may trade-off against a high death rate in low light (the cost of shade tolerance). An important set of trade-offs involve competing demands for resource capture. Thus a plant could invest in its root system to forage for phosphorus, or in its shoot system to forage for light, but it cannot maximise investment in competitive ability for light and soil nutrients. Finally, there is an important trade-off between competition and colonization because good dispersers tend to be inferior competitors; this is exemplified by the r-K continuum where colonizers (r strategists) have a set of traits like rapid generation time, small seeds, wind dispersal, and high light requirements, whereas late successional species (K strategists) tend to live longer, produce fewer, larger seeds, and to have more shade-tolerant, slowergrowing juveniles. Underpinning the theory of plant population dynamics is the invasion criterion, which states that all persistent populations must exhibit the tendency to increase when rare.

scholarly journals EFFECT OF SELENIUM-CHROME-LIPID SUBSTANCE FROM CHLORELLA VULGARIS BIEJ. ON OXIDATIVE STATUS OF RATS

2016 ◽  
Author(s):  
O. Ya. Lukashiv ◽  
O. I. Bodnar ◽  
H. B. Vinyarskа ◽  
V. V. Hrubinko
Keyword(s):  
Blood Serum ◽  
Chlorella Vulgaris ◽  
Antioxidant Status ◽  
Sodium Selenite ◽  
Oxidative Status ◽  
Unicellular Alga ◽  
Experimental Animals ◽  
Chrome Iii

By incubation unicellular alga Chlorella vulgaris Biej. in aquaculture with sodium selenite and chrome (III) sulphate there was received and allocated stable lipid and selenium, chrome-lipid substance and studied their effects on oxidative status in healthy rats experiment. Putting substances at a dose of 1.85 mсg of selenium, chrome 1.1 mcg and 0.5 mg lipid per 1 ml of 1 % aqueous starch slurry body in healthy rats every day for 14 days suppressed prooxidative processes activated antioxidant status by glutation system by reduction of catalase and superoxidedismutase activity partly in experimental animals in the liver and in blood serum.

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