scholarly journals Determination of tobacco (Nicotiana tabacum) seed vigour using controlled deterioration followed by a conductivity test

2020 ◽  
Vol 48 (1) ◽  
pp. 1-10
Author(s):  
Wen-Guang Ma ◽  
Zhi-Hao Zhang ◽  
Yun-Ye Zheng ◽  
Wei Pan ◽  
Tian Qiu ◽  
...  
Keyword(s):  
Correlation Coefficients ◽  
Germination Percentage ◽  
Germination Test ◽  
Seed Vigour ◽  
Soaking Time ◽  
Tobacco Seed ◽  
Emergence Percentage ◽  
Controlled Deterioration ◽  
Relative Conductivity

Seeds of eight lots of four tobacco varieties differing in vigour were studied. The initial germination percentage (GPUT) was 81-100% and the controlled greenhouse emergence percentage (CEP) was 55-91%. All seeds were treated by controlled deterioration (CD) at 20% moisture content and 45°C for 24 hours, then some seeds were subjected to a standard germination test and the rest of the seeds were subjected to a conductivity test. The electrical conductivity (EC) of seed soak water was measured every six hours up to 54 hours. The results showed that relative conductivity after CD (RCCD) was highly significantly correlated with GPCD after 30 to 48 hours soaking (r = -0.9324 to -0.9409, P < 0.001). After 36 and 42 hours, RCCD was significantly correlated (P < 0.01) with CEP (correlation coefficients of -0.9120 and -0.9137, respectively). Therefore, it is suggested that measuring relative conductivity after CD could be used to rank tobacco seed lots for vigour. In addition, the best seed soaking time for EC measurement is 36 to 42 hours, with respect to both efficiency and accuracy.

The assessment of the quality of sugar-beet seed

1985 ◽  
Vol 104 (1) ◽  
pp. 71-84 ◽  
Author(s):  
M. J. Durrant ◽  
S. J. Brown ◽  
A. Bould
Keyword(s):  
Sugar Beet ◽  
Field Experiments ◽  
Correlation Coefficients ◽  
Germination Percentage ◽  
Controlled Conditions ◽  
High Viability ◽  
Rate Of Emergence ◽  
Average Standard Error

SummaryThe accurate prediction of the performance of individual lots of sugar-beet seed in the field is critical when constituting blends of seed for commercial use. Previous studies indicated a need for ‘vigour tests’ to supplement the standard germination test. In many of the studies emphasis was placed on evaluation of tests in the laboratory, whereas in this study equal emphasis was placed on the determination of the values to be predicted. The performance of 20 seed lots with a range of germination between 75 and 95% was assessed in field and laboratory studies in 1981. Further investigations of ten seed lots were made in 1982 and in 1983.The results in 1981 showed little evidence of agronomically important differences in the relative performance of seed lots with respect to establishment in the field at different sites. Similarly, most seed lots showed consistent differences over a range of tests under controlled conditions. However, use of the experiment mean as a measure of stress revealed marked differences in the range of performance between the best and poorest lota in both the field and laboratory. There were clear indications that performance in the field could be modified by non-random factors that tended to reduce the magnitude of differences among seed lots. In 1982 grazing of seedlings by birds was identified as a factor that could cause greater reduction in the establishment of seed lots with high viability relative to those with low viability. Thus, under some circumstances, a single count of seedlings in non-protected field experiments can give misleading estimates of the differences among seed lots (and probably among other treatments which affect the rate of emergence). Correlation coefficients (γ) were about 0·88 for relationships between establishment from pelleted seed in plots protected from birds and germination or emergence under controlled conditions. These results reduced the need for additional vigour tests. However, the studies emphasized that small differences in germination percentage are important as they can be associated with much larger differences in establishment, particularly under adverse seed-bed conditions. The average standard error for the mean viability of individual seed lots was ±1·89 in germination tests with four replicates of 100 seeds at each of six centres. Although inincreased accuracy may not be possible without much greater replication, we found that the distinction between normal and abnormal seedlings was an important source of experimental error. A less subjective measurement, based on hypocotyl height, warrants further study.

scholarly journals Germination and Emergence of Digitaria insularis (L.) Fedde Susceptible and Resistant to Glyphosate

2019 ◽  
pp. 1-7
Author(s):  
Silvio Douglas Ferreira ◽  
Jaqueline de Araújo Barbosa ◽  
Noélle Khristinne Cordeiro
Keyword(s):  
Germination Percentage ◽  
State University ◽  
Germination Test ◽  
Original Population ◽  
Sand Box ◽  
Germination Speed ◽  
Randomized Experimental Design ◽  
Emergence Percentage ◽  
Two Stages ◽  
Selection Of

To Know the behavior shown in seed germination and emergence of Digitaria insularis (L.) Fedde enables develop strategies to reduce the seed bank in cultivated areas. The aim of this research was to evaluate the germination and emergence of weed biotypes of D. insularis susceptible and resistant to glyphosate in two substrates. The experiment was divided into two stages (germination test in BOD and emergence in sand box). In both phases of the study, it was used a completely randomized experimental design, with two treatments (weed biotypes of D. insularis susceptible and resistant to glyphosate) and ten replications. The work was done in the State University of Western Paraná, Brazil, Post-Graduation in Agronomy, between July 2018 and December 2018. In the two tests the experimental units consisted of 25 seeds of D. insularis, evenly distributed. In the germination test was evaluated the first count and the index of germination speed. In the same way, for the emergency test was evaluated the first count and the index of emergence speed. It was also calculated the germination and the emergence percentage, total number of germinated seeds, total number of emerged plants. Differences were observed in the first count, index of germination speed and germination percentage, seeds of D. insularis susceptible and resistant to glyphosate. During the first count, susceptible biotype showed higher germination, with 78% of compared to resistant. Similar behavior was observed for the index of germination speed and for the germination percentage, in which the susceptible biotype surpassed in 80.4% and 47%, respectively, the resistant biotype. Conclusion: The selection of D. insularis biotypes resistant to glyphosate affects the germination and emergence, the species in relation to the original population of susceptible biotypes. For each 100 seeds of the biotype resistant to glyphosate 53 seeds of them germinate and 32.6 seeds can emerge.

scholarly journals Early counts of radicle emergence, counted manually and by image analysis, can reveal differences in the production of normal seedlings and the vigour of seed lots of cauliflower

2021 ◽  
Author(s):  
Takashi Shinohara ◽  
Sylvie Ducournau ◽  
Stan Matthews ◽  
Marie-Helene Wagner ◽  
Alison A. Powell
Keyword(s):  
Image Analysis ◽  
Seed Quality ◽  
Automated Image Analysis ◽  
Genotypic Differences ◽  
Germination Test ◽  
Seed Vigour ◽  
Seed Ageing ◽  
Radicle Emergence ◽  
Controlled Deterioration ◽  
Initial Seed

The ability of a single early count of radicle emergence (RE) to predict differences in the production of normal seedlings (NG) and seed vigour was examined in four seed lots from each of three varieties of cauliflower (Brassica oleracea var botrytis). Initial seed quality was assessed in germination and controlled deterioration (CD) vigour tests. RE (first appearance of the radicle) was counted manually after 48 hours in the germination test (RE 48h 20/30&deg;C) and every two hours for 144 hours at 20&deg;C using automated image analysis. Seed vigour was assessed in field and glasshouse trials. A large proportion of the variance in NG was explained by the RE count. The same RE counts at 20/30&deg;C and 20&deg;C predicted seed vigour in the field and glasshouse and revealed the same vigour differences as the validated CD test. Differences in vigour (field and glasshouse emergence) observed between varieties were related to the extent of previously sustained seed ageing revealed by the CD test, although genotypic differences in vigour could not be excluded. We propose that single counts of RE taken manually or by image analysis can be used to reveal differences in the NG and vigour of seed lots of cauliflower.

scholarly journals Estimation of Barley Seed Vigour with Respect to Variety and Provenance Effects

2011 ◽  
Vol 42 (No. 2) ◽  
pp. 44-49 ◽  
Author(s):  
P. Hrstková ◽  
O. Chloupek ◽  
J. Bébarová
Keyword(s):  
Seed Quality ◽  
Spring Barley ◽  
Germination Test ◽  
Seed Vigour ◽  
Testing Method ◽  
Controlled Deterioration ◽  
Growing Conditions ◽  
One Year ◽  
Post Hoc

The study was aimed at determining potential differences in seed quality of spring and winter barley in relation to varieties (four winter and two spring barley varieties) and growing conditions (six locations, two years). Three tests were performed on each seed sample, i.e. (1) the standard germination test; (2) the low temperature and drought stress germination test and (3) the germination test in a salt solution. The effects of the factors of variety, provenance and year on seed vigour were estimated by the analysis of variance and Tukey&rsquo;s post hoc test. The germination of winter varieties was influenced by provenance, both measures of vigour (2&nbsp;and 3) by year, and significant differences between varieties were found in all three traits. Spring varieties differed only in germination and vigour (3) in one year when the influence of provenance prevailed. The results show different effects of variety and provenance on seed vigour. This could be promising for the breeding of high vigour barley varieties. Some preliminary results were obtained by using controlled deterioration (CD) as a&nbsp;vigour testing method for barley. The suitable conditions seem to be the combination of 45&deg;C and 24% moisture content for the period of 24 hours. &nbsp;

scholarly journals Using seed respiration as a tool for calculating optimal soaking times for ‘on-farm’ seed priming of barley (Hordeum vulgare)

2021 ◽  
pp. 1-9
Author(s):  
Javier Carrillo-Reche ◽  
Adrian C. Newton ◽  
Richard S. Quilliam
Keyword(s):  
Morphological Changes ◽  
Low Cost ◽  
Germination Rate ◽  
Seed Priming ◽  
Embryonic Axes ◽  
Seedling Vigour ◽  
Soaking Time ◽  
On Farm ◽  
Seed Respiration

Abstract A low-cost technique named ‘on-farm’ seed priming is increasingly being recognized as an effective approach to maximize crop establishment. It consists of anaerobically soaking seeds in water before sowing resulting in rapid and uniform germination, and enhanced seedling vigour. The extent of these benefits depends on the soaking time. The current determination of optimal soaking time by germination assays and mini-plot trials is resource-intensive, as it is species/genotype-specific. This study aimed to determine the potential of the seed respiration rate (an indicator of metabolic activity) and seed morphological changes during barley priming as predictors of the priming benefits and, thus, facilitate the determination of optimal soaking times. A series of germination tests revealed that the germination rate is mostly attributable to the rapid hydration of embryo tissues, as the highest gains in the germination rate occurred before the resumption of respiration. Germination uniformity, however, was not significantly improved until seeds were primed for at least 8 h, that is, after a first respiration burst was initiated. The maximum seedling vigour was attained when the priming was stopped just before the beginning of the differentiation of embryonic axes (20 h) after which vigour began to decrease (‘over-priming’). The onset of embryonic axis elongation was preceded by a second respiration burst, which can be used as a marker for priming optimization. Thus, monitoring of seed respiration provides a rapid and inexpensive alternative to the current practice. The method could be carried out by agricultural institutions to provide recommended optimal soaking times for the common barley varieties within a specific region.

Compartmental transfer of mercury released from amalgam

1997 ◽  
Vol 16 (11) ◽  
pp. 667-672 ◽  
Author(s):  
S. Halbach ◽  
L. Kremers ◽  
H. Willruth ◽  
A. Mehl ◽  
G. Welzl ◽  
...  
Keyword(s):  
Oral Cavity ◽  
Urinary Excretion ◽  
Total Mercury ◽  
Excretion Rate ◽  
Absorbed Dose ◽  
Correlation Coefficients ◽  
Urinary Excretion Rate ◽  
Amalgam Fillings

The number of amalgam-covered surfaces and the occlusal area of the fillings, the concentrations of total mercury in plasma, erythrocytes and urine, the urinary excretion rate, and the absorbed daily doses estimated by two separate methods from intra-oral Hg emission were determined in 29 volunteers with a low amalgam load. The transfer ofHg from the fillings via the oral cavity and blood to urinary excretion was evaluated by multiple correla tions between these variables. In addition, the combina tion of variables most representative of the entire compartmental transfer of amalgam Hg was determined. Urinary excretion (1), Hg concentration in plasma (2) and absorbed dose (3) were most closely correlated to each other, followed by correlations with the variables of the fillings (4). Correlation coefficients were 0.75 for variables 1 vs 2 and 2 vs 3, and 0.49 for variables 3 vs 4. It was concluded that variables 1-3 best reflected the transfer of mercury from amalgam fillings throughout the organism and that they were relatively insensitive to dietary mercury. The determination of total mercury in plasma and of its urinary excretion rate appears, under practical aspects, most suitable for the investigation of Hg uptake from amalgam.

EMERGENCE AND SEEDLING GROWTH OF INBRED LINES OF CORN AT SUBOPTIMAL ROOT-ZONE TEMPERATURES

1987 ◽  
Vol 67 (2) ◽  
pp. 409-415 ◽  
Author(s):  
A. MENKIR ◽  
E. N. LARTER
Keyword(s):  
Zea Mays ◽  
Seedling Growth ◽  
Root Zone ◽  
Seedling Emergence ◽  
Correlation Coefficients ◽  
Dry Weight ◽  
Inbred Lines ◽  
Root Zone Temperature ◽  
Emergence Percentage ◽  
Zone Temperature

Based on the results of an earlier paper, 12 inbred lines of corn (Zea mays L.) were evaluated for emergence and seedling growth at three controlled root-zone temperatures (10, 14, and 18 °C). Low root-zone temperatures, 10 and 14 °C, were detrimental to emergence, seedling growth, and root growth of all inbred lines. Differential responses of inbred lines were observed within each temperature regime. The differences in seedling emergence among lines became smaller with increasing root-zone temperature, while the reverse was true for seedling dry weight. Simple correlation coefficients showed a significantly (P = 0.05) negative association between emergence percentage and emergence index (rate). Neither of these two emergence traits was significantly correlated with seedling dry weights. Seedling dry weights were significantly (P = 0.01) and positively associated with root dry weights. Two inbred lines exhibited good tolerance to low root-zone temperatures, viz. CO255 and RB214. A significant and positive correlation existed between emergence percentage at a root-zone temperature of 10 °C and field emergence in test with the same genotypes reported earlier. Selection at a root-zone temperature of 10 °C for a high percentage of seedling emergence, therefore, could be effective in identifying genotypes capable of germinating in cool soils. Furthermore, the significantly (P = 0.01) positive relationship between seedling dry weights at all root-zone temperatures and those from the field test suggest that strains with vigorous seedling growth in the field could be identified using low root-zone temperature regimes.Key words: Zea mays, root-zone temperature, cold tolerance

scholarly journals An Ultrasound Assessed Extraction Combined with Ion-Pair HPLC Method and Risk Assessment of Nitrite and Nitrate in Cured Meat

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Babiker Yagoub Abdulkair ◽  
Amin O. Elzupir ◽  
Abdulaziz S. Alamer
Keyword(s):  
Risk Assessment ◽  
Tetrabutylammonium Bromide ◽  
Meat Products ◽  
Correlation Coefficients ◽  
Dietary Exposure ◽  
Hplc Method ◽  
Processed Meat ◽  
Disodium Hydrogen Phosphate ◽  
Cured Meat

An accurate IPC-UV method was developed and validated for the determination of nitrite (NI) and nitrate (NA) in meat products. The best separation was achieved on a phenyl-hexyl column (150 mm × 4.6 mm, 3 µm) with a mobile phase composed of 25% acetonitrile and 75% buffer (2 mM disodium hydrogen phosphate and 3 mM tetrabutylammonium bromide, pH = 4). Eluents were monitored at 205 nm. Linearity ranges were 1.86 × 10−6–7.5 µg·ml−1 and 0.09–5.0 µg·ml−1 for NI and NA, respectively. The correlation coefficients were greater than 0.999 for NI and NA. This method was applied to a number of processed meat products in Riyadh (n = 155). NI ranged from 1.78 to 129.69 mg·kg−1, and NA ranged from 0.76 to 96.64 mg·kg−1. Results showed extensive use of NI and NA; however, concentrations were within the legal limit of Saudi Arabia except for one sample. Further, the risk assessment and dietary exposure have been estimated for both NI and NA.

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