scholarly journals Predicting Evolutionary Consequences of Greater Reproductive Effort in Tripsacum Dactyloides, a Perennial Grass

Ecology ◽  
1994 ◽  
Vol 75 (3) ◽  
pp. 627-641 ◽  
Author(s):  
Laura L. Jackson ◽  
Chester L. Dewald
Keyword(s):  
Reproductive Effort ◽  
Perennial Grass ◽  
Tripsacum Dactyloides ◽  
Evolutionary Consequences

Effects of soil moisture and light intensity on the chasmogamous and cleistogamous components of reproductive effort of Dichanthelium clandestinum populations

1987 ◽  
Vol 65 (11) ◽  
pp. 2243-2249 ◽  
Author(s):  
Timothy J. Bell ◽  
James A. Quinn
Keyword(s):  
Soil Moisture ◽  
Biomass Allocation ◽  
Reproductive Effort ◽  
Environmental Gradients ◽  
Perennial Grass ◽  
Moisture Gradient ◽  
Sharp Drop ◽  
Population Responses ◽  
Steady Decrease ◽  
Significant Difference

Plants from six New Jersey populations of Dichanthelium clandestinum, a perennial grass with chasmogamous and cleistogamous flowers on the same individual, showed significant differences in their responses to decreasing light and soil moisture, but chasmogamous reproductive effort was always less than cleistogamous. In an experiment with three light treatments, populations were significantly different in biomass allocation to chasmogamous and cleistogamous reproduction and varied as to which light treatment produced the most significant difference between chasmogamous and cleistogamous allocation. In an experiment using soil moisture gradient boxes, chasmogamous reproductive effort remained relatively constant over the moisture gradient for all six populations; however, for five populations, percentage biomass allocation to cleistogamous reproduction was significantly lower at low soil moistures. The population responses formed a continuum from no difference in allocation to cleistogamy along the moisture gradient to a sharp drop in cleistogamous allocation at the lower end of the gradient to a relatively steady decrease in cleistogamous allocation with decreasing soil moisture. These results indicate genetically based differences in phenotypic plasticity and underscore the need to use more than one population of a species when research is conducted on variation in relative allocation to chasmogamous and cleistogamous reproduction along environmental gradients.

scholarly journals Aging parasites produce offspring with poor fitness prospects

2017 ◽  
Vol 13 (2) ◽  
pp. 20160888 ◽  
Author(s):  
Cédric Lippens ◽  
Bruno Faivre ◽  
Clothilde Lechenault ◽  
Gabriele Sorci
Keyword(s):  
Reproductive Effort ◽  
Intestinal Parasite ◽  
Optimal Schedule ◽  
Parasitic Nematodes ◽  
Parental Age ◽  
Poor Survival ◽  
Heligmosomoides Polygyrus ◽  
Offspring Quality ◽  
Age Dependent ◽  
Evolutionary Consequences

Senescing individuals have poor survival prospects and low fecundity. They can also produce offspring with reduced survival and reproductive success. We tested the effect of parental age on the performance of descendants in the nematode Heligmosomoides polygyrus , an intestinal parasite of rodents. We found that offspring of senescing worms had reduced within-host survival and reduced egg shedding over the first month post-infection compared with offspring produced by young parents. These results suggest that declining offspring quality is a component of senescence in parasitic nematodes and might have evolutionary consequences for the optimal schedule of age-dependent investment into reproductive effort.

The yield of perennial grass stands on drained organic soils of Steppe

2016 ◽  
Vol 1 (90) ◽  
pp. 92-97
Author(s):  
I.T. Slusar ◽  
V.A. Serbenyuk ◽  
A.N. Gera ◽  
A.P. Solyanik ◽  
A.A. Tarasenko
Keyword(s):  
Zinc Sulphate ◽  
Foliar Application ◽  
Perennial Grass ◽  
Mineral Fertilizer ◽  
Dry Weight ◽  
Research Area ◽  
Organic Soils ◽  
Growth Promoters ◽  
Cobalt Sulfate ◽  
The Impact

Research on the impact of the introduction of micro fertilizers and growth promoters on a background of mineral fertilizer and without N90R45К120 spent on old peat in shallow carbonate floodplain r.Supiy, Yahotyn Kyiv region. Power peat horizon about 60-70 cm, 7,4-7,6 pH of the aqueous extract, stupas schedule 56-60%, density 0,49-0,52 assembly soil, total nitrogen content (%) - 1.9; gross forms of phosphorus - 0,4, potassium 0.2, 20% lime. In experiments studying biological rehoplant, radustym, Biolan, emistim, Jets, humisol, plantafol, radyfarm and micronutrients: copper, boric acid, manganese sulphate, zinc sulphate, potassium humates. Treatment drugs conducted in the spring by spraying mixtures. Space research area of 60 m2, three-time repetition. It is established that the use of growth stimulants and micronutrients in the background N90R45К120 provided the highest yield mixtures of years, against making BIOLan - 9.9 t / ha Radyfarmu - 9.6 t / ha Radostymu 9.3 t / ha dry weight. In areas for making other preparations were intermediate yield growth rates - 0.5 - 2.0 t / ha dry weight. Also good gains herbage yields obtained by making all kinds of micronutrients and growth stimulants in the background without making makrodobryv which was within 5.3 - 6.9 t / ha to control without fertilization - 4.5 t / ha dry weight. In deep peat copper fertilizer (25 kg / ha of copper sulphate or 5 kg / ha pirytnoho cinders) in all zones should be making every 3-4 years, and zinc, cobalt and molybdenum advisable to make time for the growing season, spring, by foliar application in such numbers: ammonium molibdenovokyslyy - 0.3 kg / ha; cobalt sulfate - 3 kg / ha zinc sulphate 0.5 kg / ha or placers these salts should be mixed with major fertilizer.

High Reproductive Effort and Low Recruitment Rates of European Beech: Is There a Limit for the Superior Competitor?

2015 ◽  
Vol 63 (2) ◽  
pp. 198-212 ◽  
Author(s):  
Jerzy Szwagrzyk ◽  
Georg Gratzer ◽  
Hanna Stępniewska ◽  
Janusz Szewczyk ◽  
Bojana Veselinovic
Keyword(s):  
Reproductive Effort ◽  
European Beech ◽  
High Reproductive Effort

Environmental control of germination and dormancy of seeds of two cytotypes of Lygeum spartum L., a perennial grass of semi-arid and arid areas in Algeria

2010 ◽  
Vol 36 (1) ◽  
pp. 89-98 ◽  
Author(s):  
Abderazak Djabeur ◽  
Meriem Kaid-Harche ◽  
Daniel Côme ◽  
Françoise Corbineau
Keyword(s):  
Environmental Control ◽  
Perennial Grass ◽  
Arid Areas ◽  
Semi Arid

Hymenachne acutigluma (Steud.) Gilliland in GBS 20:314 - An exceptionally important perennial grass for anatomy and indigenous practice.

2016 ◽  
Vol 5 (04) ◽  
pp. 4958
Author(s):  
Dulal De
Keyword(s):  
Perennial Grass ◽  
Secondary Growth ◽  
Grass Species ◽  
Stem Anatomy

Hymenachne acutigluma (Steud.) Gilliland, a robust rhizomatous perennial grass spreads on moist and swampy land and also floating in water. Being a grass species, they do not have any cambium for secondary growth. A peculiarity in stem anatomy especially the spongy pith of secondary tissues found in absence of the cambium. The origin and development of the parenchymatous pith tissues has been investigated in the present study. Economically this spongy pith is of very much potent for its high absorbing and filtering capacity and also used as a good fodder.

Evolutionary Consequences of Asymmetric Dispersal Rates

2002 ◽  
Vol 160 (3) ◽  
pp. 333
Author(s):  
Kawecki ◽  
Holt
Keyword(s):  
Asymmetric Dispersal ◽  
Evolutionary Consequences
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