scholarly journals The Influence of New and Artificial Aged Microplastic and Leachates on the Germination of Lepidium sativum L.

Plants ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 339 ◽  
Author(s):  
Stephan Pflugmacher ◽  
Amalia Sulek ◽  
Hannah Mader ◽  
Jeongin Heo ◽  
Ji Hyeon Noh ◽  
...  

With the increase in environmental monitoring and assessing, we are gaining insight into the extent of microplastic pollution in our environment. The threat posed by microplastics to biota could come, e.g., from leached substances. As some plastic materials have been decaying in nature for extended periods already, the toxic effects of leaching compounds need to be investigated. It is furthermore essential to understand the adverse effects of new plastic and how these effects differ from the effects elicited by old plastic material. Therefore, in the present study, the effects of exposure to leachates from new and artificial aged polycarbonate as well as new and aged polycarbonate granules on various germination parameters of Lepidium sativum were studied. Germination, root, and shoot length, as well as the calculated germination rate index as a measure for germination speed, was negatively influenced in substrate-free and substrate containing exposures. From an ecological and agricultural point of view, this implies possible yield losses with less germinating seeds, slower plant germination speed, and smaller seedlings in general.

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 944
Author(s):  
Moon-Sun Yeom ◽  
Thi Kim Loan Nguyen ◽  
Ju-Sung Cho ◽  
Myung-Min Oh

The medicinal plant, coastal glehnia (Glehnia littoralis F. Schmidt ex Miq.), belongs to the Apiaceae, which is known to exhibit morpho-physiological seed dormancy (MPD). In this study, we aimed to determine the dormancy type of this plant, along with the conditions for breaking dormancy, and how to increase its germination rate for mass production. Initially, the seeds of coastal glehnia had undeveloped embryos, which gradually developed following cold (5 °C) stratification over eight weeks. The embryo to seed (E:S) ratio increased to 66.7%, confirming that the seeds had the MPD type. Coastal glehnia seeds with pericarp did not show inhibited water uptake, and the germination inhibitory chemicals were not detected. However, removal of the pericarp improved the final germination percentage, germination speed, and T50 of coastal glehnia seeds compared with those of seeds with pericarp at 20 °C, which showed the highest value compared with other temperature treatments. Thus, cold stratification at 5 °C for eight weeks and removing the pericarp of germinating seeds maintained at 20 °C is efficient ways to break dormancy and improve the germination rate for the mass production of coastal glehnia.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1819
Author(s):  
Toma-Leonida Dragomir ◽  
Ana-Maria Pană ◽  
Valentin Ordodi ◽  
Vasile Gherman ◽  
Gabriela-Alina Dumitrel ◽  
...  

Pollution caused by plastic materials has a great impact on the environment. The biodegradation process is a good treatment solution for common polymers and biodegradation susceptible ones. The present work introduces new insight into the biodegradation process from a mathematical point of view, as it envisions a new empirical model for this complex process. The model is an exponential function with two different time constants and a time delay, which follows the weight loss profile of the polymer during the biodegradation process. Moreover, this function can be generated as the output variable of a dynamic exogenous system described through state equations. The newly developed models displayed a good fit against the experimental data, as shown by statistical indicators. In addition, the new empirical model was compared to kinetics models available in the literature and the correlation coefficients were closest to 1 for the new empirical model in all discussed cases. The mathematical operations were performed in the MATLAB Simulink environment.


1992 ◽  
Vol 72 (2) ◽  
pp. 177-181 ◽  
Author(s):  
Suzanne Beauchemin ◽  
Marc R. Laverdière ◽  
Adrien N’dayegamiye

A germination test with cress (Lepidium sativum L.) was carried out to evaluate the phytotoxic effects of extracts from fresh and composted tree clippings. Water-soluble extracts from unground and ground material were compared with a soil solution and distilled water in relation to their effect on germination and plant root development. Water-soluble and ethanol-soluble extracts from fresh tree clippings were strongly acidic, but they were neutral for the composted material. Greater quantities were extracted by water and alcohol from fresh material than from composted material. Water-soluble products extracted from fresh ligneous materials decreased the rate of germination of cress very significantly compared with those obtained from composted tree clippings. Grinding the clippings further reduced the germination rate, through the apparent liberation of more phytotoxic products. Composting of tree clippings significantly decreased the phytotoxicity of the organic amendment. Key words: Composting, cress, germination, phytotoxicity, wood residues, tree clippings


The results of experimental studies of masonry on the action of dynamic and static (short-term and long-term) loads are presented. The possibility of plastic deformations in the masonry is analyzed for different types of force effects. The falsity of the proposed approach to the estimation of the coefficient of plasticity of masonry, taking into account the ratio of elastic and total deformations of the masonry is noted. The study of the works of Soviet scientists revealed that the masonry under the action of seismic loads refers to brittle materials in the complete absence of plastic properties in it in the process of instantaneous application of forces. For the cases of uniaxial and plane stress states of the masonry, data on the coefficient of plasticity obtained from the experiment are presented. On the basis of experimental studies the influence of the strength of the so-called base materials (brick, mortar) on the bearing capacity of the masonry, regardless of the nature of the application of forces and the type of its stress state, is noted. The analysis of works of prof. S. V. Polyakov makes it possible to draw a conclusion that at the long application of the load, characteristic for the masonry are not plastic deformations, but creep deformations. It is shown that the proposals of some authors on the need to reduce the level of adhesion of the mortar to the brick for the masonry erected in earthquake-prone regions in order to improve its plastic properties are erroneous both from the structural point of view and from the point of view of ensuring the seismic resistance of structures. It is noted that the proposal to assess the plasticity of the masonry of ceramic brick walls and large-format ceramic stone with a voidness of more than 20% is incorrect, and does not meet the work of the masonry of hollow material. On the basis of the analysis of a large number of research works it is concluded about the fragile work of masonry.


Healthcare ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 726
Author(s):  
Fulvia Ceccarelli ◽  
Venusia Covelli ◽  
Giulio Olivieri ◽  
Francesco Natalucci ◽  
Fabrizio Conti

Background: The COVID-19 pandemic contributes to the burden of living with different diseases, including Systemic Lupus Erythematosus (SLE). We described, from a narrative point of view, the experiences and perspectives of Italian SLE adults during the COVID-19 emergency, by distinguishing the illness experience before and after the lockdown. Methods: Fifteen patients were invited to participate. Illness narratives were collected between 22 and 29 March 2020 using a written modality to capture patients’ perspectives before and after the COVID-19 lockdown. We performed a two-fold analysis of collected data by distinguishing three narrative types and a qualitative analysis of content to identify the relevant themes and sub-themes reported. Results: Eight narratives included in the final analysis (mean length 436.9 words) have been written by eight females (mean age 43.3 ± 9.9 years, mean disease duration 13.1 ± 7.4 years). Six patients provided a quest narrative, one a chaos and the remaining one a restitution narrative. By text content analysis, we identified specific themes, temporally distinct before and after the lockdown. Before COVID-19, all the patients referred to a good control of disease, however the unexpected arrival of the COVID-19 emergency broke a balance, and patients perceived the loss of health status control, with anxiety and stress. Conclusions: We provided unique insight into the experiences of people with SLE at the time of COVID-19, underlining the perspective of patients in relation to the pandemic.


2021 ◽  
pp. 136078042110184
Author(s):  
Leja Markelj ◽  
Alisa Selan ◽  
Tjaša Dolinar ◽  
Matej Sande

The research comprehensively identifies the needs and problems of sex workers in Slovenia from the point of view of three groups of actors in a decriminalized setting. The objective of the rapid needs assessment was to identify the needs of sex workers as perceived by themselves. In order to gain a deeper insight into this topic, we analyzed the functioning of the organizations working with the population, and examined the perspective of the clients. The results of the study show that no aid programmes have been developed for sex workers, even though organizations from various fields often come in contact with this population. Sex workers express the need to be informed about various topics (health, the law, legal advice) and emphasize client relations as the primary issue. The findings indicate the need for the development of a specialized aid programmes to address the fields of advocacy, reducing social distress and providing psychosocial assistance.


Ecotoxicology ◽  
2021 ◽  
Vol 30 (2) ◽  
pp. 277-291
Author(s):  
D. Montvydienė ◽  
A. Jagminas ◽  
Ž. Jurgelėnė ◽  
M. Kazlauskas ◽  
R. Butrimienė ◽  
...  

Environments ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 49
Author(s):  
Markéta Šourková ◽  
Dana Adamcová ◽  
Jan Winkler ◽  
Magdalena Daria Vaverková

Illegal dumps and landfills with disposed of tires are a fact of today, which should not be neglected as they represent a great ecological burden for the environment, affect the surrounding nature and disturb the landscape. This research was focused on testing the phytotoxicity of aqueous leachates from the fractions of tires in two sets of experiments—to simulate laboratory conditions (tire leaching in distilled water) and natural conditions (tire leaching in water from a recipient) using the Phytotoxkit testing kit (kit for the establishment of inhibition/stimulation effect on the root development) and the watercress test of phytotoxicity (biological method for the assessment of leachate phytotoxicity). Plants whose seeds were selected for the test were watercress (Lepidium sativum L.) and white mustard (Sinapis alba L.). The aqueous leachate was tested for 38 weeks. During the experiment, physical and chemical parameters were measured at intervals of 14 days by the testing instrument HACH TEST KIT: electric conductivity (EC), amount of dissolved oxygen (LDO) and pH. Results of root growth inhibition (IR) on the seeds of Lepidium sativum L. and Sinapis alba L. exhibited values ranging from 11.73% to 47.74% in the tested samples. Results of germination index (GI) on the seeds of Lepidium sativum L. exhibited values below 66% in the tested samples, which indicated the leachate phytotoxicity. In spite of the fact that similar studies are tackling the acute toxicity of leachates from tires (particularly to algae, embryos and animals), this research brings complementary information in testing the acute phytotoxicity of tire leachates to higher plants.


Plants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1076
Author(s):  
Döme Barna ◽  
Szilvia Kisvarga ◽  
Szilvia Kovács ◽  
Gábor Csatári ◽  
Ibolya O. Tóth ◽  
...  

Organic and ecological farming programs require new and efficient biostimulants with beneficial properties for the sustainable and safe production of seedlings and ornamental plants. We examined the effect of non-fermented and lacto-fermented alfalfa brown juice (BJ) on seed germination and the vegetative, physiological, and anatomical properties of French marigold (Tagetes patula L. ‘Csemő’) plants which were treated with 0.5–10% fermented and non-fermented BJ, with tap water applied as a control. Applying 0.5% fermented BJ significantly improved seed germination compared with non-fermented BJ, resulting in an increase of 9.6, 11.2, 10.9, and 41.7% in the final germination percent, germination rate index, germination index, and vigor index, respectively. In addition, it increased the root and shoot length by 7.9 and 16.1%, respectively, root and shoot dry mass by 20 and 47.6%, respectively, and the number of leaves by 28.8% compared to the control. Furthermore, an increase in contents of water-soluble phenol, chlorophyll a and b, and carotenoid was reported upon the application of 0.5% fermented BJ, while peroxidase activity decreased. Our results prove that alfalfa BJ can be enrolled as a biostimulant as part of the circular farming approach which supports the sustainable horticultural practice.


1982 ◽  
Vol 37 (9) ◽  
pp. 793-801 ◽  
Author(s):  
Rudolf Karl ◽  
Wolfhart Rüdiger

Extracts from oat husks inhibit germination of a variety of seeds including Avena sativa L., Sorghum spec., Phalleris spec., Raphanus spec., Amaranthus caudatus, Lepidium sativum L. A quantitative assay for this inhibition was developed on the basis of percentage of root growth of Avena in the presence of extracted material compared with root growth of water controls. Fractionation of the extracts revealed that about half of the total inhibitory activity was found in the fraction of free organic acids. The inhibition was not due to known inhibitors. Abscisic acid. was not found in this extract. Phenole carbonic acids were determined in the extract. Their con­centration was too low to significantly contribute to the observed inhibitory activity.


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