scholarly journals Tetrazolium test to evaluate viability and vigour in Genipa americana seeds

Author(s):  
Paulo Bruno Santos das Virgens ◽  
Taise Almeida Conceição ◽  
Rafael Marani Barbosa

Evaluating the vigour and viability of seeds can help in the production of seed lots with proven high physiological potential. In this regard, the tetrazolium (TZ) test is efficient, rapid and inexpensive; however, it not been fully explored for forest species. Further development of species-specific methodologies is required in order to maximise the test efficacy. The objective of this work was to define a tetrazolium test protocol to evaluate the vigour and viability of Genipa americana L seeds. Fruits and seeds were characterised for biometry and initial water content before and after hydration. Germination, germination speed index, electrical conductivity and seedling emergence was also performed. For the TZ test, G. americana seeds were cut longitudinally and submitted to different seed pre-conditioning methods (with and without 24 hours imbibition), different TZ concentrations (0.05, 0.075, 0.10 and 0.25%) and three immersion periods (2, 3 and 4 hours). The tetrazolium test allowed adequate evaluation of seed vigour levels (Viable; Viable and non-vigourous; and Non-viable). Immersion of non-imbibed seeds in 0.10% TZ solution, for three hours is the most efficient protocol for evaluating the vigour and viability of G. americana seeds.

Biologia ◽  
2017 ◽  
Vol 72 (8) ◽  
Author(s):  
M. Teresa Mas ◽  
Antoni M.C. Verdú ◽  
Marta Ginovart ◽  
Ramon Josa

AbstractIt is well known that soil sealing strongly affects seedling emergence. The effect of soil sealing on the emergence of flax and turnip seedlings was studied in the laboratory. Seeds were sown in pots, watered, then covered with loamy soil and water was added. Three different doses of water were tested. Soil sealing was obtained with a paste of soil mixed with distilled water, added to each pot as a thick homogeneous, continuous and isotropic layer. The initial water content of the seal was measured. When seedling emergence was observed (or at the end of the experiment in the case of event failure), seal strength was measured in situ by a firmness pressure tester (used as a penetrometer). Relationships between water loss and initial moisture of the seal versus mechanical impedance were obtained. Differences in emergence success between species depended on the initial soil water content as well as on the initial seal moisture. A model of seedling emergence success of the two species, flax and turnip, as a function of the initial seal moisture content was obtained using a binary logistic regression model.


2021 ◽  
Vol 42 (3) ◽  
pp. 949-962
Author(s):  
Jéssica de Lucena Marinho ◽  
◽  
José Henrique Bizzarri Bazzo ◽  
Claudemir Zucareli ◽  
Inês Cristina de Batista Fonseca ◽  
...  

The evaluation of the physiological potential of sweet corn seeds is essential in a quality control program and the choice of vigor tests using an adequate analysis methodology is essential to obtain reliable results. In this sense, this study aimed to standardize the methodology of the controlled deterioration test through combinations between time and temperature to evaluate the vigor of sweet corn seeds. Six lots of sweet corn seeds were characterized by the degree of moisture and the initial physiological potential through the following tests: germination, first germination count, cold test, electrical conductivity, accelerated aging, length and dry mass of normal seedlings, seedling emergence in sand, and emergence rate index. Subsequently, these lots had their initial water content adjusted to 20% using the wet substrate method. The seeds from the six lots were subjected to the controlled deterioration test under two temperatures for four periods, obtaining a completely randomized design in an 8 × 6 factorial scheme with eight combinations of time/temperature and six lots. Germination and the first germination count were evaluated after the deterioration test. The data were subjected to analysis of variance with a comparison of means by the Tukey test at a 5% significance. The results of the first count and germination tests after deterioration were subjected to a simple linear correlation study together with the initial characterization data. The combinations 8 h – 40 °C and 8 h – 45 °C in the controlled deterioration test were efficient in distinguishing the vigor of seed lots. The shorter exposure period and the first germination count after deterioration are more suitable for evaluating the vigor of sweet corn seeds.


Author(s):  
Y. Feng ◽  
X. Y. Cai ◽  
R. J. Kelley ◽  
D. C. Larbalestier

The issue of strong flux pinning is crucial to the further development of high critical current density Bi-Sr-Ca-Cu-O (BSCCO) superconductors in conductor-like applications, yet the pinning mechanisms are still much debated. Anomalous peaks in the M-H (magnetization vs. magnetic field) loops are commonly observed in Bi2Sr2CaCu2Oy (Bi-2212) single crystals. Oxygen vacancies may be effective flux pinning centers in BSCCO, as has been found in YBCO. However, it has also been proposed that basal-plane dislocation networks also act as effective pinning centers. Yang et al. proposed that the characteristic scale of the basal-plane dislocation networksmay strongly depend on oxygen content and the anomalous peak in the M-H loop at ˜20-30K may be due tothe flux pinning of decoupled two-dimensional pancake vortices by the dislocation networks. In light of this, we have performed an insitu observation on the dislocation networks precisely at the same region before and after annealing in air, vacuumand oxygen, in order to verify whether the dislocation networks change with varying oxygen content Inall cases, we have not found any noticeable changes in dislocation structure, regardless of the drastic changes in Tc and the anomalous magnetization. Therefore, it does not appear that the anomalous peak in the M-H loops is controlled by the basal-plane dislocation networks.


Author(s):  
Bashkim Selmani ◽  
Bekim Maksuti

The profound changes within the Albanian society, including Albania, Kosovo and Macedonia, before and after they proclaimed independence (in exception of Albania), with the establishment of the parliamentary system resulted in mass spread social negative consequences such as crime, drugs, prostitution, child beggars on the street etc. As a result of these occurred circumstances emerged a substantial need for changes within the legal system in order to meet and achieve the European standards or behaviors and the need for adoption of many laws imported from abroad, but without actually reading the factual situation of the psycho-economic position of the citizens and the consequences of the peoples’ occupations without proper compensation, as a remedy for the victims of war or peace in these countries. The sad truth is that the perpetrators not only weren’t sanctioned, but these regions remained an untouched haven for further development of criminal activities, be it from the public state officials through property privatization or in the private field. The organized crime groups, almost in all cases, are perceived by the human mind as “Mafia” and it is a fact that this cannot be denied easily. The widely spread term “Mafia” is mostly known around the world to define criminal organizations.The Balkan Peninsula is highly involved in these illegal groups of organized crime whose practice of criminal activities is largely extended through the Balkan countries such as Kosovo, Albania, Macedonia, Serbia, Bosnia, Croatia, Montenegro, etc. Many factors contributed to these strategic countries to be part of these types of activities. In general, some of the countries have been affected more specifically, but in all of the abovementioned countries organized crime has affected all areas of life, leaving a black mark in the history of these states.


2003 ◽  
Vol 27 (08) ◽  
pp. 301-304
Author(s):  
Gavin Reid ◽  
Mark Hughson

Aims and Method We conducted a postal questionnaire survey of the practice of rapid tranquillisation among 215 consultant psychiatrists in the West of Scotland, before and after the withdrawal of droperidol by the manufacturer. Results One hundred and eighty questionnaires (84% of those sent) were returned. Droperidol had been used extensively, often combined with lorazepam, for rapid tranquillisation. The main replacement suggested for droperidol was haloperidol. About half of the respondents to our survey chose to comment on the withdrawal of droperidol. More than half of the comments were unfavourable, including lack of an adequate replacement and lack of consultation with the psychiatric profession. Clinical Implications The abrupt withdrawal of droperidol, partly for commercial reasons, was regrettable. There was no time for an adequate evaluation of possible replacement medications and a lack of consultation with the profession regarding the impact on clinical care.


Author(s):  
Xiaobing Li ◽  
Jianpeng Chen ◽  
Xiuqing Hu ◽  
Hongtao Fu ◽  
Jun Wang ◽  
...  

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 90
Author(s):  
Andrzej Bryś ◽  
Joanna Bryś ◽  
Marko Obranović ◽  
Dubravka Škevin ◽  
Szymon Głowacki ◽  
...  

The olive oil industry represents an important productive sector in the Mediterranean basin countries. Olive stone is an essential by-product generated in the olive oil extraction industries and it represents roughly 10% by weight of the olive fruit. The seeds of pickled olives are also a significant waste product. In the present study, we have investigated the possibility of the use of differential scanning calorimetry for the thermal characterization of seeds from green and black pickled olives from Croatia. The differential scanning calorimeter (DSC) with a normal pressure cell equipped with a cooling system was used to determine the thermal properties of seeds from olives. The following analyses were also performed: the determination of calorific values in a pressure bomb calorimeter, the determination of initial water content, the determination of changes of water content during drying at the temperatures of 30 °C, 50 °C and 80 °C, the determination of a percentage content of seeds mass to the mass of the whole olives, and the determination of ash content. Seeds from olives are characterized by very good parameters as a biomass. The analyzed olive seeds were characterized by low water content, low ash content, and a relatively high caloric value.


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1176
Author(s):  
Hanna Dorna ◽  
Agnieszka Rosińska ◽  
Dorota Szopińska

Alternaria dauci (J.G. Kühn) J.W. Groves et Skolko and A. radicina Meier, Drechsler et E.D. Eddy are important seed-transmitted pathogens of carrot. The aim of this study was to evaluate the effects of acetic acid treatments on the quality of stored carrot seeds. Seeds of two samples were soaked for 30 min in 0.5, 1 and 2% acetic acid. Controls included untreated seeds, seeds soaked in distilled water and seeds treated with fungicide Zaprawa Nasienna T 75 WS/DS (a.i. thiram 75%). Germination, vigour and health of untreated and treated seeds were evaluated before and after 5 and 12 months of storage at 4 and 20 °C. Seeds of both samples treated with 0.5 and 1% acetic acid were characterized by higher germination capacity after storage than untreated seeds. However, treatments with 1 and 2% acetic acid negatively affected seed vigour. Generally, seeds of both samples treated with acetic acid were characterized by lower infestation with A. alternata and A. radicina after storage than untreated seeds and seeds soaked in distilled water. Moreover, acetic acid often controlled these fungi more effectively than the fungicide. Regardless of the storage duration, infestation with fungi was higher if seeds of both samples were stored at a lower temperature.


2013 ◽  
Vol 19 (1) ◽  
pp. 9-15 ◽  
Author(s):  
Zhiqing Li ◽  
Chuan Tang ◽  
Ruilin Hu ◽  
Yingxin Zhou

According to Mengzi expansive soil, consolidated drained tests and undrained tests are carried on under saturated and remoulded conditions. The stress-strain characteristics of saturated soil are researched systematically under different confining pressure, initial dry density, initial water content, shearing rate and drainage condition. The inherent unity of diversity of shearing strength for the same samples measured by different experimental methods is indicated according to the normalization of critical state test results. And the failure lines in p ‘- q - ν space of remoulded saturated expansive soil under consolidated drained and undrained conditions are attained. The hyperbolic curve model can fit well the weak hardening stress-strain curves and the exponential curve model can fit the weak softening stress-strain curves. The test results can provide technical parameters and theoretical help for shearing strength variation of slope during rainfall and strength state of soil structure in normal water level.


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