scholarly journals Seed germination and performance of sunflower seedlings submitted to produced water

2021 ◽  
Vol 45 ◽  
Author(s):  
Claudia Antonia Vieira Rossetto ◽  
Leonardo Oliveira Medici ◽  
Camila Santos Barros de Morais ◽  
Rosária da Costa Faria Martins ◽  
Daniel Fonseca de Carvalho

ABSTRACT The use of produced water becomes an option in the irrigation of non-food crops with potential for biofuel production. However, its effects on different stages of plant development and mainly on seed germination should be known. The study was conducted to evaluate the performance of sunflower seedlings subjected to different types of produced water. An experimental design in a factorial scheme was adopted to evaluate 3 cultivars (Catissol 01, Embrapa 122 and IAC Iaramã) and 6 types of water (distilled water - control, public-supply water, water resulting from the water and oil separation process - WOS, filtration in sand filter - SAF, filtration in sand + charcoal filter - SCF, and filtration in sand + osmosis filter - SOF). In addition, the substrate was moistened with polyethylene glycol (PEG) solutions, simulating the osmotic potentials of the evaluated waters, and a sensitivity test was conducted with lettuce seeds under conditions similar to those adopted for sunflower. The cv. Catissol showed higher percentages of germination and vigor of seedlings, regardless of the water used. There was a trend of reduction in germination and vigor of seedlings with the use of produced water treated with the WOS, SAF and SCF systems. All water potentials simulated by PEG solutions reduced the germination and vigor of lettuce seeds, and the effect was more pronounced for the WOS system. SOF was the only one capable of making the produced water non-toxic to sunflower seeds and lettuce seedlings.

2010 ◽  
Vol 96 (3) ◽  
pp. 8-15 ◽  
Author(s):  
Elizabeth S. Grace ◽  
Elizabeth J. Korinek ◽  
Zung V. Tran

ABSTRACT This study compares key characteristics and performance of physicians referred to a clinical competence assessment and education program by state medical boards (boards) and hospitals. Physicians referred by boards (400) and by hospitals (102) completed a CPEP clinical competence assessment between July 2002 and June 2010. Key characteristics, self-reported specialty, and average performance rating for each group are reported and compared. Results show that, compared with hospital-referred physicians, board-referred physicians were more likely to be male (75.5% versus 88.3%), older (average age 54.1 versus 50.3 years), and less likely to be currently specialty board certified (80.4% versus 61.8%). On a scale of 1 (best) to 4 (worst), average performance was 2.62 for board referrals and 2.36 for hospital referrals. There were no significant differences between board and hospital referrals in the percentage of physicians who graduated from U.S. and Canadian medical schools. The most common specialties referred differed for boards and hospitals. Conclusion: Characteristics of physicians referred to a clinical competence program by boards and hospitals differ in important respects. The authors consider the potential reasons for these differences and whether boards and hospitals are dealing with different subsets of physicians with different types of performance problems. Further study is warranted.


Author(s):  
Mohammad Rizk Assaf ◽  
Abdel-Nasser Assimi

In this article, the authors investigate the enhanced two stage MMSE (TS-MMSE) equalizer in bit-interleaved coded FBMC/OQAM system which gives a tradeoff between complexity and performance, since error correcting codes limits error propagation, so this allows the equalizer to remove not only ICI but also ISI in the second stage. The proposed equalizer has shown less design complexity compared to the other MMSE equalizers. The obtained results show that the probability of error is improved where SNR gain reaches 2 dB measured at BER compared with ICI cancellation for different types of modulation schemes and ITU Vehicular B channel model. Some simulation results are provided to illustrate the effectiveness of the proposed equalizer.


Helia ◽  
2001 ◽  
Vol 24 (34) ◽  
pp. 77-82 ◽  
Author(s):  
Rauf Bhutta ◽  
M.H. Rahber Bhatti ◽  
Ahmad Iftikhar

SUMMARYAll four seed diffusates used for treatment of sunflower seeds, Azadirachtaindica, Capsicum annuum, Coriandrum sativum and Eugenia jambulana, reduced the populations of seed-borne fungi: Alternaria alternata, Drechslera tetramera, Emericellopsis terricola, Fusarium moniliforme, F.semitectum, Macrophomina phaseolina and Phoma oleracea. Of four seed diffusates, those from A.indica and C.sativum controlled the fungal populations almost 100%. Seed germination was increased in seed samples of both sunflower cultivars under study, HO-1 and NK-212. The obtained results indicate that seed diffusates could substitute costly chemicals for safe control of seed-borne diseases, protecting at the same time the environment from chemical pollution.


2021 ◽  
pp. 147612702098287
Author(s):  
Peng Wang ◽  
Xu Jiang ◽  
Maggie Chuoyan Dong

Alliance experience has been a frequent topic in strategic alliance research in recent decades. Nonetheless, its performance consequences, either as a whole or differentiated into general versus partner-specific alliance experience, are neither theoretically clear nor empirically consistent. We use a range of meta-analytic techniques to integrate the empirical findings of 143 studies and provide a more conclusive assessment compared to prior research. Our study thus addresses a long-standing, understudied, and controversial topic: the distinction between the two types of alliance experiences. Going beyond traditional sub-group analysis, we reveal the contextual contingencies by examining how different types of alliance experiences and performance outcomes jointly affect the alliance experience–performance relationship. Moreover, we identify critical country-level institutional contingencies that moderate the focal effect.


2020 ◽  
pp. 107780042096013
Author(s):  
Pille Pruulmann-Vengerfeldt

This article discusses how different forms of autoethnographic production prompted by diverse forms of academic self-expression can lead to different types of knowing. Utilizing five examples from the Massive_Microscopic project, where participants responded to 21 different prompts inviting autoethnographic reflections about COVID-19 global pandemic, the article explores the responses from the perspective of alternative ways of knowing, reflecting on questions of motherhood, self-care, and performance in academia. Whether visual, rhythmic, or text produced from the perspective of things, the different modalities of the prompts allowed unexpected knowledge to emerge and supported deeper and more colorful reflections. Exploring the personal experience with the pandemic is expanded by the qualitative inquiry supported by different (self-)expression formats.


2018 ◽  
Vol 40 (1) ◽  
pp. 36-43 ◽  
Author(s):  
Ayslan Trindade Lima ◽  
Paulo Henrique de Jesus da Cunha ◽  
Bárbara França Dantas ◽  
Marcos Vinicius Meiado

Abstract: Seed hydration memory is the ability of seeds to retain biochemical and physiological changes caused by discontinuous hydration. This study aimed to determine if Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S.Irwin & Barneby (Fabaceae) present seed memory and evaluate the effects of hydration and dehydration cycles (HD) on the seed germination of this species when submitted to conditions of water stress. Seeds underwent HD cycles (0, 1, 2 and 3 cycles) corresponding to the hydration times X (6 hours), Y (16 hours) and Z (24 hours), determined from the imbibition curve, with 5 hours of dehydration and submitted to water stress conditions. Germination was evaluated at 0.0, -0.1, -0.3, -0.6 and -0.9 MPa, obtained with polyethylene glycol 6000 solution. Germinability (%), mean germination time (days) and hydrotime (MPa d-1) were calculated. The seeds of S. spectabilis var. excelsa are sensitive to the low osmotic potentials tested in this study, however, when submitted to the HD cycles of 16 hours hydration (time Y), the tolerance to water stress conditions is increased. In addition, the observed benefits on the evaluated germination parameters show that S. spectabilis var. excelsa present seed hydation memory.


2003 ◽  
Vol 60 (3) ◽  
pp. 477-480 ◽  
Author(s):  
Warley Marcos Nascimento

Lettuce (Lactuca sativa L.) seed germination is strongly temperature dependent and under high temperatures, germination of most of genotypes can be erratic or completely inhibited. Lettuce seeds of 'Dark Green Boston' (DGB) were incubated at temperatures ranging from 15° to 35°C at light and dark conditions. Other seeds were imbibed in dark at 20°; 25°; 30°; and 35°C for 8 and 16 hours and then transferred to 20 or 35°C, in dark. Seeds were also incubated at constant temperature of 20° and 35 °C, in the dark, as control. In another treatment, seeds were primed for 3 days at 15°C with constant light. DGB lettuce seeds required light to germinate adequately at temperatures above 25°C. Seeds incubated at 20°C had 97% germination, whereas seeds incubated at 35°C did not germinate. Seeds imbibed at 20°C for 8 and 16 hours had germination. At 35°C, seeds imbibed initially at 20°C for 8 and 16 hours, had 89 and 97% germination, respectively. Seeds imbibed at 25°C for 16 hours, germinated satisfactory at 35°C. High temperatures of imbibition led to no germination. Primed and non-primed seeds had 100% germination at 20°C. Primed seeds had 100% germination at 35°C, whereas non-primed seeds germinate only 4%. The first hours of imbibition are very critical for lettuce seed germination at high temperatures.


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