scholarly journals Transgenerational Effects of Environmentally Relevant Concentrations of Atrazine and Glyphosate Herbicides, Isolated and in Mixture, to Freshwater Microcrustacean Daphnia Magna

2021 ◽  
Author(s):  
Wanessa A Ramsdorf ◽  
Eduarda Roberta Bordin ◽  
Renan cesar Munhoz ◽  
Paloma Pucholobek Panicio ◽  
Adriane Martins Freitas
Keyword(s):  
Daphnia Magna ◽  
First Generation ◽  
Reproductive Capacity ◽  
Long Term Effects ◽  
Glutathione S Transferase ◽  
Biochemical Biomarkers ◽  
Two Generations ◽  
Test Organisms ◽  
Herbicide Mixture ◽  
Analytical Standards

Abstract Herbicide mixture is used as an alternative to obtain different mechanisms of action acting on weeds, resulting in the frequent presence of pesticides in environmental compartments. As they are products used worldwide, this study evaluated effects of environmentally relevant concentrations of the analytical standards and commercial formulations of the herbicides atrazine (2 µg L− 1) and glyphosate (65 µg L− 1), in isolation and also in mixture (2 + 65 µg L− 1) on the microcrustacean Daphnia magna. Through chronic exposure (21 days) of two generations of organisms, effects on survival and reproductive capacity were observed, as well as responses regarding oxidative stress, determined through the analysis of biochemical biomarkers such as catalase and glutathione S-transferase. In the evaluation of the first generation of test organisms, no significant results related to biochemical biomarkers were observed, only effects over sexual maturation of organisms. However, in the second generation of exposed organisms, changes were observed in all parameters evaluated, with the mixture of herbicide active principles being the treatment responsible for more significant responses (p < 0.05). A statistical difference (p < 0.05) was also observed between analytical standards and commercial formulations, indicating that other components present in the formulations can change the toxicity of the products. Given the difficulty of estimating the effects of mixtures and considering that various stressors are found in the environment, our results support the need to carry out studies that address long-term effects and, above all, that verify what the impacts are across generations, so that the toxicity of products is not underestimated.

Parental breeding age effects on descendants’ longevity interact over two generations in matrilines and patrilines

2019 ◽  
Author(s):  
Zac Wylde ◽  
Foteini Spagopoulou ◽  
Amy K Hooper ◽  
Alexei A Maklakov ◽  
Russell Bonduriansky
Keyword(s):  
Maternal Age ◽  
First Generation ◽  
Age Effects ◽  
Population Variation ◽  
Paternal Age ◽  
Interactive Effects ◽  
Competitive Environment ◽  
Larval Diet ◽  
Negative Effects ◽  
Two Generations

Individuals within populations vary enormously in mortality risk and longevity, but the causes of this variation remain poorly understood. A potentially important and phylogenetically widespread source of such variation is maternal age at breeding, which typically has negative effects on offspring longevity. Here, we show that paternal age can affect offspring longevity as strongly as maternal age does, and that breeding age effects can interact over two generations in both matrilines and patrilines. We manipulated maternal and paternal ages at breeding over two generations in the neriid fly Telostylinus angusticollis. To determine whether breeding age effects can be modulated by the environment, we also manipulated larval diet and male competitive environment in the first generation. We found separate and interactive effects of parental and grandparental ages at breeding on descendants’ mortality rate and lifespan in both matrilines and patrilines. These breeding age effects were not modulated by grandparental larval diet quality or competitive environment. Our findings suggest that variation in maternal and paternal ages at breeding could contribute substantially to intra-population variation in mortality and longevity.

FINDING FACTORS OF SURVIVAL THE YOUNG OF MARINE HERRING MIGRATING IN THE NORTHERN PART OF THE CASPIAN SEA

2017 ◽  
pp. 19-25
Author(s):  
Tatiana Stanislavovna Zubkova
Keyword(s):  
First Generation ◽  
Environmental Influence ◽  
Reproductive Capacity ◽  
Individual Species ◽  
Survival Ratio ◽  
The Caspian Sea ◽  
Foraging Area ◽  
Starting Point ◽  
Feeding Assessment ◽  
Predatory Fishes

The objects of research are three species of Caspian migrating herrings (Dolginsk herring ( Alosa brashnikowi ), big-eyed shad ( Alosa saposchnikowii ), Caspian shad ( Alosa caspia caspia )). The work considers two biological aspects of herring reproduction: dependence of number of underyearlings on the number of females in the end of feeding; assessment of survival rate of herring juveniles from the stage of fish egg to the stage of underyearlings. Besides fecundity of individual species, scientists take into account sex ratio in spawning populations, population fecundity, loss of reproductive capacity due to the resorption in unscreened roe. The materials obtained within 2009-2015 show that the dependence of herring underyearling number on the number of females arriving at spawning ground is extremely low. Despite a great number of females on the spawning grounds, the reasons of decreasing number of the first generation can be different: unfavorable hydrological and hydrochemical environment in foraging area, insufficient nutritive base, rescheduling of the spawning etc. The varying number of underyearlings from year to year is more pronounced with predatory fishes: the Dolginsk herring - 2.1 times, big-eyed shad - 1.7 times. The underyearling number of zoo-plankton feeder - Caspian shad is consistently high with minimal yearly variations. The young of Caspian shad have the highest survival ratio (0.0122); the young of predatory herring species the ratio is lower: Dolginsk herring is 4 times less (0.0031), big-eyed shad - 5 times less (0.0024). The data on herring survival from stage of a fish egg to an underyearling stage will become a starting point in the investigation of the environmental influence on to the new herring generations.

A Standard Primary Toxicity Bioassay Using Daphnia Magna as a Test Species

1977 ◽  
Vol 12 (1) ◽  
pp. 27-50 ◽  
Author(s):  
L.A. Behie ◽  
J.E. Zajic ◽  
D. Berk ◽  
R.J.P. Brouzes ◽  
V.A. Naish
Keyword(s):  
Statistical Analysis ◽  
Daphnia Magna ◽  
Biological Indicator ◽  
Pulp And Paper ◽  
Toxicity Bioassay ◽  
Simple Method ◽  
Test Species ◽  
Test Organisms ◽  
Dilution Water

Abstract Although Daphnia magna have been widely used in the determination of the toxicity of various substances, there are no reports in the literature that describe a rigorous bioassay method using this organism as a test species. The test described herein involves the standariza-tion of various important aspects of the method such as the age of the test organisms, and the dilution water used for the preparation of the various toxicant concentrations. Also described is a simple method for the statistical analysis of the results. The sensitivity of the proposed bioassay is demonstrated by determining the toxicity of various pulp and paper effluents. Finally, extensive bioassays were carried out simultaneously with rainbow trout and Daphnia magna indicating that Daphnia are as good a biological indicator of acute toxicity as fish.

Effect of Mercury on the Survival of Daphnia Magna

1990 ◽  
Vol 22 (5) ◽  
pp. 241-246 ◽  
Author(s):  
I. Brković-Popović
Keyword(s):  
Life Span ◽  
Daphnia Magna ◽  
Abiotic Factors ◽  
Total Hardness ◽  
Chemical Characteristics ◽  
Effect Concentration ◽  
Test Organisms ◽  
Lethal Time ◽  
Two Temperatures ◽  
Time Required

The median lethal time (LT) for each concentration of mercury was determined on the basis of mortality curves. Toxicity curves (i.e., the median life-span of Daphniamagna, LT 50, versus the concentration of mercury) for four tested conditions are shown. The experiments were carried out using two diluents of different total hardness (46 and 119 mg/l as CaCO3), at two temperatures (20°C and 25°C). A comparison of the LT 50s of the control organisms with the LT 50s of the test organisms at mercury concentrations of 0.0075 and 0.0050 mg. l-1 showed that the chemical characteristics and temperatures of the mediums tested did not affect the range of the ‘no effect' concentration. However, the incipient LC 50, and the time required for its appearance, did depend on the combination of the abiotic factors tested.

Conservation or change? Exploring trends in Modern Hebrew in light of new spoken corpora of the first two generations of speakers

2020 ◽  
Vol 54 (s41) ◽  
pp. 89-115
Author(s):  
Einat Gonen
Keyword(s):  
Early Modern ◽  
First Generation ◽  
Linguistic Features ◽  
The Feminine ◽  
Two Generations ◽  
Modern Hebrew ◽  
Small Set ◽  
Diachronic Study ◽  
The 1950S

Abstract This paper presents a diachronic study of Modern Hebrew agreement between numerals and their quantified nouns. This research is possible thanks to the discovery of two rare collections of recordings from the 1950s and 1960s, which document four generations of speakers and have become important sources of spoken Early Modern Hebrew. On the basis of these two corpora, I compare numeral agreement in the first two generations of speakers with present-day usage and analyze trends of change and conversation in Modern Hebrew. The study shows that the first generation of speakers (“Gen1”) largely acquired the gender distinction of cardinals. However, in contrast to other agreement issues that educated Gen1 speakers realized fully, numeral use showed variation and absence of agreement in a small set of cases. Moreover, some linguistic features of Gen1 Hebrew found in this study no longer characterize Present-Day Hebrew; among these features is prosodic conditioning, which led to a Gen1 tendency to use the feminine form of the numeral ‘four’ with masculine nouns more frequently than was the case with other numerals.

Investigating the process of electrocoagulation in the removal of azo dye from synthetic textile effluents and the effects of acute toxicity on Daphnia magna test organisms

2022 ◽  
Vol 45 ◽  
pp. 102485
Author(s):  
Carlos Eduardo Lach ◽  
Camila Schwarz Pauli ◽  
Aline Scheller Coan ◽  
Edesio Luiz Simionatto ◽  
Luciano André Deitos Koslowski
Keyword(s):  
Acute Toxicity ◽  
Daphnia Magna ◽  
Azo Dye ◽  
Textile Effluents ◽  
Test Organisms

scholarly journals Aquatic Toxicity Comparison of Silver Nanoparticles and Silver Nanowires

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Eun Kyung Sohn ◽  
Seyed Ali Johari ◽  
Tae Gyu Kim ◽  
Jin Kwon Kim ◽  
Ellen Kim ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Daphnia Magna ◽  
Silver Nanowires ◽  
Aquatic Toxicity ◽  
Oryzias Latipes ◽  
Aquatic Environments ◽  
Silver Nanomaterials ◽  
Raphidocelis Subcapitata ◽  
Test Organisms ◽  
Test Fish

To better understand the potential ecotoxicological impact of silver nanoparticles (AgNPs) and silver nanowires (AgNWs) released into freshwater environments, the toxicities of these nanomaterials were assessed and compared using Organization for Economic Cooperation and Development (OECD) test guidelines, including a “Daphniasp., acute immobilization test,” “Fish, acute toxicity test,” and “freshwater alga and cyanobacteria, growth inhibition test.” Based on the estimated median lethal/effective concentrations of AgNPs and AgNWs, the susceptibility to the nanomaterials was different among test organisms (daphnia > algae > fish), suggesting that the AgNPs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 1” forRaphidocelis subcapitata, while the AgNWs are classified as “category acute 1” forDaphnia magna, “category acute 2” forOryzias latipes, and “category acute 2” forRaphidocelis subcapitata, according to the GHS (Globally Harmonized System of Classification and Labelling of Chemicals). In conclusion, the present results suggest that more attention should be paid to prevent the accidental or intentional release of silver nanomaterials into freshwater aquatic environments.

SEASONAL HISTORY, ADULT FLIGHT ACTIVITY, AND DAMAGE OF THE OBLIQUEBANDED LEAFROLLER, CHORISTONEURA ROSACEANA (LEPIDOPTERA: TORTRICIDAE), IN FILBERT ORCHARDS

1986 ◽  
Vol 118 (4) ◽  
pp. 351-359 ◽  
Author(s):  
M.T. AliNiazee
Keyword(s):  
First Generation ◽  
Adult Emergence ◽  
Flight Activity ◽  
Yield Reduction ◽  
Larval Feeding ◽  
Choristoneura Rosaceana ◽  
Periodic Field ◽  
Obliquebanded Leafroller ◽  
Two Generations ◽  
Seasonal History

AbstractSeasonal history, adult flight activity, and damage of the obliquebanded leafroller, Choristoneura rosaceana (Harris), on filbert were studied during a 7-year period between 1976 and 1984. Data from periodic field counts and moth catches in sex-attractant traps indicated two generations per year. The first-generation adult capture peak was generally higher than the second, except in 1978 when about an equal number of moths were trapped from both generations. A physiological time scale, using degree-days (DD), was devised for predicting emergence of obliquebanded leafroller adults. The first adults from overwintering larvae emerged at approximately 374 DD above a threshold of 10 °C starting 1 March. A total of 1172 DD were required between the first and the last adult emergence during the first generation and about 519 DD during the second generation. The obliquebanded leafroller causes both foliar and nut damage in filbert orchards of Oregon. Foliar damage was insignificant, but nut damage, caused exclusively by the first-generation larvae during June and early July, was highly destructive. Larval feeding on nuts caused staining and premature drop of infested nuts resulting in substantial yield reduction in heavily infested orchards.

scholarly journals Petrography and zircon morphology of syntectonic granitoids rocks of Hafafit area, South Eastern Desert (Egypt).

2013 ◽  
Vol 47 (1) ◽  
pp. 438 ◽  
Author(s):  
I. Thabet ◽  
A. Kilias ◽  
A. Koroneos ◽  
S. Kamh
Keyword(s):  
First Generation ◽  
Morphological Characteristics ◽  
Crystal Form ◽  
Eastern Desert ◽  
Elongation Ratio ◽  
Crystal Length ◽  
Rock Types ◽  
Two Generations ◽  
Granitoid Rocks ◽  
Zircon Morphology

The study deals with the petrography of the granitoid rocks intruding the five (A to E) domes of Hafafit Culmination. The morphological characteristics of zircon crystals are also examined, in order to elucidate the genesis of zircon and their host Hafafit granitoids. The granitoid rocks are tonalites, granodiorites and quartz diorites, all exhibiting gneissic texture. The zircon crystals from all the rock types intruding each one of the domes are examined in detail for colour, inclusions, crystal length, crystal width, elongation ratio, crystal form and habit, degree of roundness and corrosion, and are distinguished in groups on the basis of the previous characteristics. Two generations of zircons have been recognized; the first generation with magmatic features and the second one with post magmatic features. The first generation of zircon is attributed to the subduction, magmatic and deformation events while the second generation of zircon is attributed to metamorphism.

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