Factors Affecting Eclipta (Eclipta prostrata) Seed Germination

1996 ◽  
Vol 10 (4) ◽  
pp. 727-731 ◽  
Author(s):  
John V. Altom ◽  
Don S. Murray
Keyword(s):  
Seed Germination ◽  
Incubation Period ◽  
Effect Of Temperature ◽  
Distilled Water ◽  
Solution Ph ◽  
Factors Affecting ◽  
Water Potentials ◽  
Light Intensities ◽  
Eclipta Prostrata ◽  
Water Ph

Controlled environmental chamber experiments were conducted for a 14-d incubation period to measure the effect of temperature, light, light intensity, water potential, and pH on eclipta seed germination. In full light, seed germinated over a range of 10 to 35 C; however, germination was highest at 83% at 35 C. Seeds were strongly photoblastic with none germinating in the dark. Seeds germinated in light intensities between 6 and 100% of full light. Seeds germinated 78 to 88% in water potentials of 0.0, −0.1, and −0.2 MPa. In distilled water (pH ∼ 5.5) and a buffered solution pH 6 and 7, seeds germinated 85 to 89%; however, some seeds germinated in a buffered solution pH range of 5 to 8. After the first 14-d incubation period, ungerminated seeds were transferred to distilled water and incubated at 35 C in full light for 4 to 6 d as a second incubation period. Seeds germinated 89 to 96% after this second incubation period when first incubation was at temperatures 10 to 35 C in full light or darkness, light intensities 0 to 100% of full light, water potentials 0.0 to −0.8 MPa, and buffered solution pH levels of 5.5 to 7.

scholarly journals EXPLORATION OF THE FACTORS AFFECTING THE SOLUBLE PROTEIN EXTRACTION FROM CULTURED SNAKEHEAD FISH (Channa striata) MUSCLE

2018 ◽  
Vol 55 (5A) ◽  
pp. 74
Author(s):  
Vo Hoang Ngan
Keyword(s):  
Soluble Protein ◽  
Extraction Efficiency ◽  
Protein Extraction ◽  
Ph Value ◽  
Fish Muscle ◽  
Effect Of Temperature ◽  
Extraction Temperature ◽  
Solution Ph ◽  
Factors Affecting ◽  
Optimum Extraction

This study was conducted to identify the factors affecting the soluble protein extraction from cultured snakehead fish muscle, a protein having bioavailability and nutritional value. The study investigated the ratio of fish muscle to water (from 1:1 to 1:5 w/v) and salt (NaCl) concentration (from 0.05 M to 0.25 M) that are suitable for extracting soluble protein effectively. Research has applied a response surface methodology using a central composite design to optimize the effect of temperature and time extraction on soluble protein extraction efficiency. In addition, the study investigated the effect of pH of salt solution (pH 2 to pH 12) on the efficiency of soluble protein extraction from cultured snakehead fish muscle. As a result, the use of 0.15 M NaCl solution with 1:2 ratio of fish muscle to water gave high soluble protein extraction efficiency. The optimum extraction temperature and time were determined as 34.8 °C and 15.2 min respectively, and the appropriate pH value was also determined as pH 10. At the optimum extraction conditions, soluble protein recovery calculated by the amount of soluble protein extraction dividing total protein of fish muscle was 14.39 ± 0.18 %.

scholarly journals Factors affecting germination of great bindweed (Calystegia silvatica) seeds

2019 ◽  
Vol 72 ◽  
pp. 147-152
Author(s):  
Kerry C. Harrington ◽  
Tracey L. Gawn ◽  
Cory Matthew ◽  
Hossein Ghanizadeh
Keyword(s):  
Seed Germination ◽  
Seed Banks ◽  
Effect Of Temperature ◽  
Dormancy Breaking ◽  
Factors Affecting ◽  
Hard Seed ◽  
Factors Influencing ◽  
Viable Seeds ◽  
Hard Seed Coat ◽  
Number Of Seeds

Great bindweed (Calystegia silvatica) invades riparian plantings in New Zealand but little is known about the factors influencing seed germination of this species, the number of seeds produced per flower or whether seed banks build up in the soil below infested sites. Dormancy-breaking treatments involving scarification and/or pre-chilling of seeds were evaluated. The effect of temperature on germination was also studied. The presence of viable seeds in capsules on vines and in the soil beneath established stands was quantified. Great bindweed seeds needed scarification but not a period of cold temperature to germinate. Germination occurred from 5oC to 25oC but germination was greater and more rapid at higher temperatures. Seed capsules contained an average of only 2.3 seeds, and the soil beneath plants had, on average, only 21.9 seeds/m2. Seeds were large with one thousand seeds weighing 43.4 g. Once the hard seed coat is broken, seeds will germinate readily at warmer times of the year, but seed production is not prolific so seeds might not be that important for spread of the species.

scholarly journals Factors Affecting Seed Production in Transgenic Ethylene-insensitive Petunias

2004 ◽  
Vol 129 (3) ◽  
pp. 401-406 ◽  
Author(s):  
Donna J. Clevenger ◽  
James E. Barrett ◽  
Harry J. Klee ◽  
David G. Clark
Keyword(s):  
Seed Germination ◽  
Fruit Ripening ◽  
Seed Weight ◽  
Pollen Viability ◽  
Dry Mass ◽  
Effect Of Temperature ◽  
Flower Senescence ◽  
Paternal Effects ◽  
Factors Affecting

Pollen viability, in-vivo pollen tube growth, fruit ripening, seed germination, seed weight, whole plant vigor, and natural flower senescence were investigated in homozygous and heterozygous transgenic ethylene-insensitive CaMV35S::etr1-1 petunias (Petunia ×hybrida `Mitchell Diploid'). Homozygous or heterozygous plants were used to determine any maternal and/or paternal effects of the CaMV35S::etr1-1 transgene. All experiments except for those used to determine natural flower senescence characteristics were conducted in both high and low temperature greenhouses to determine the effect of temperature stress on transgenic plants when compared to wild-type. Results indicated that ethylene-insensitive plants had a decrease in pollen viability, root dry mass, seed weight, and seed germination. Fruit ripening, seed germination, and seed weight were maternally regulated. In contrast, the CaMV35S::etr1-1 transgene is completely dominant in its effect on natural flower senescence.

scholarly journals Soaking curve and effect of temperature on the germination of daisy seeds

2012 ◽  
Vol 30 (2) ◽  
pp. 312-316 ◽  
Author(s):  
Rogério G Pêgo ◽  
José Antônio S Grossi ◽  
José Geraldo Barbosa
Keyword(s):  
Seed Germination ◽  
Effect Of Temperature ◽  
Distilled Water ◽  
Germination Test ◽  
Tukey Test ◽  
Germination Process ◽  
Randomized Experimental Design ◽  
Chrysanthemum Leucanthemum ◽  
Triphasic Pattern

The soaking curve and the effect of temperature on the germination of daisy seeds (Chrysanthemum leucanthemum) were characterized in this study. To determine the soaking curve, four samples of 0.5 g of seeds were soaked in germitest paper moistened with distilled water and maintained in germinator at 25ºC. The seeds were weighed in periods of 0, 3, 6, 9, 12, 24, 36, 48, 60, 72, 84 and 96 hours using a precision digital balance of 0.0001 g. A triphasic pattern germination curve was adjusted, allowing the determination of the beginning and duration of the phase II of the germination process. The germination test was carried out with four replications of 50 seeds disposed in "Gerbox" boxes and placed in germinators at the temperatures of 20, 25, 30 or 20-30ºC. A completely randomized experimental design was used with four replications of 50 seeds. The data were submitted to the analysis of variance and the averages were compared by the Tukey test, at 5% of probability. For analysis of accumulated seed germination, regressions were adjusted based on period of experiment. The seeds presented a triphasic pattern of germination and the phases I and II lasted 12 and 48 hours, respectively. The best temperature for the germination of the seeds is 25ºC. The temperature of 30ºC promoted the thermoinhibition of germination and increased the dead and dormant seeds and abnormal seedlings.

scholarly journals Assessing the germinability of coastal Limonium minutum (Plumbaginaceae) under different temperature and salinity conditions: implications for its conservation

2021 ◽  
Vol 154 (3) ◽  
pp. 332-340
Author(s):  
Carles Cardona ◽  
Iván Cortés ◽  
Pere M. Mir ◽  
Lorenzo Gil
Keyword(s):  
Seed Germination ◽  
Germination Percentage ◽  
Balearic Islands ◽  
Effect Of Temperature ◽  
Distilled Water ◽  
Endemic Plant ◽  
Effects Of Temperature ◽  
Rocky Habitats ◽  
Almost All ◽  
Saline Solutions

Background and aims – Limonium minutum is an endemic plant of the eastern Balearic Islands (Majorca and Minorca), where it grows in coastal rocky habitats. The effects of temperature and salinity on seed germination of Limonium minutum were evaluated in order to set a protocol for recovery of this species in this habitat.Material and methods – Experiments to determine the effect of temperature have been carried out at temperature conditions between 10 and 23°C. Tests to determine the effect of salinity have been evaluated at 18°C with concentrations of 0, 100, 200, 300, and 400 mM of MgCl2, MgSO4, NaCl, and Na2SO4.Key results – Maximum germination took place between 16 and 20°C. Based on the salinity tests, the highest germination values were obtained with distilled water. The use of saline solutions resulted in significant decreases in the germination percentage. However, in almost all treatments, seed germination was observed. The T50 increased at low temperatures and with increasing salt concentration.Conclusion – Limonium minutum has a wide germination temperature range and a high resistance to salinity. After being exposed to different saline solutions, once washed with distilled water, the seeds recover their full germination capacity; therefore, the effect of salts is an osmotic and non-toxic effect for this species. Sowing seeds in late August ensures that the species has an optimal chance to survive in coastal habitats.

Effect of Temperature on ADP-Induced Platelet Aggregation

1973 ◽  
Vol 29 (01) ◽  
pp. 183-189
Author(s):  
C. A Praga ◽  
E. M Pogliani
Keyword(s):  
Platelet Aggregation ◽  
Incubation Period ◽  
Room Temperature ◽  
Important Variable ◽  
Practical Significance ◽  
Effect Of Temperature ◽  
Induce Platelet Aggregation ◽  
Cuvette Holder ◽  
Exact Temperature

SummaryTemperature represents a very important variable in ADP-induced platelet aggregation.When low doses of ADP ( < 1 (μM) are used to induce platelet aggregation, the length of the incubation period of PRP in the cuvette holder of the aggregometer, thermostatted at 37° C, is very critical. Samples of the same PRP previously kept at room temperature, were incubated for increasing periods of time in the cuvette of the aggregometer before adding ADP, and a significant decrease of aggregation, proportional to the length of incubation, was observed. Stirring of the PRP during the incubation period made these changes more evident.To measure the exact temperature of the PRP during incubation in the aggre- gometer, a thermocouple device was used. While the temperature of the cuvette holder was stable at 37° C, the PRP temperature itself increased exponentially, taking about ten minutes from the beginning of the incubation to reach the value of 37° C. The above results have a practical significance in the reproducibility of the platelet aggregation test in vitro and acquire particular value when the effect of inhibitors of ADP induced platelet aggregation is studied.Experiments carried out with three anti-aggregating agents (acetyl salicyclic acid, dipyridamole and metergoline) have shown that the incubation conditions which influence both the effect of the drugs on platelets and the ADP breakdown in plasma must be strictly controlled.

DETERMINATION OF AFTER-RIPENING PERIOD AND HORMONAL RESPONSE OF OROBANCHE SOLMSII C.D. CLARKE SEEDS

1970 ◽  
Vol 11 (1) ◽  
Author(s):  
A. Bista ◽  
G. B. Khattri ◽  
B. D. Acharya ◽  
S. C. Srivastava
Keyword(s):  
Growth Hormone ◽  
Seed Germination ◽  
Key Words ◽  
Incubation Period ◽  
Seed Set ◽  
Summer Season ◽  
Conditioning Period ◽  
Root Parasite ◽  
One Year

To find out the ability of Orobanche seeds to germinate immediately after seed set, seeds were germinated periodically at an interval of three months for one year in GR24. Some Orobanche seeds were capable of germination immediately after seed set but most required about nine months as after ripening or incubation period to be able to germinate. The phenomenon of after ripening in Orobanche seeds could be taken as an ecological measure to dormant over following unfavorable wet summer season. The growth hormone studies on Orobanche seed germination have shown that GA3 at a concentration of 100 ppm substantially enhanced seed germination when applied during pre-conditioning period. NAA showed some stimulatory effect at 0.5 - 1.0 ppm when applied during post-conditioning period but the hormone if applied during pre-conditioning period inhibited the germination. Kinetin failed to stimulate the germination at all the concentrations tested. Key words: Germination, root-parasite, hormone. Ecoprint Vol.11(1) 2004.

Seed-borne fungi of cowpea [Vigna unguiculata (L.) Walp] and their possible control in vitro using locally available fungicides in Botswana.

2016 ◽  
Vol 5 (11) ◽  
pp. 5016 ◽  
Author(s):  
K. B. Khare* ◽  
Loeto D. ◽  
Wale K. ◽  
Salani M.
Keyword(s):  
Seed Germination ◽  
Continuous Light ◽  
Sodium Hypochlorite Solution ◽  
Distilled Water ◽  
Percentage Germination ◽  
Department Of Agriculture ◽  
Hypochlorite Solution ◽  
Cowpea Cultivars ◽  
Petri Plate

Seeds of three cowpea cultivars namely Black eye, ER 7 and Tswana obtained from the Department of Agriculture Research, Gaborone were tested for the presence of seed-borne fungi, and their possible control in vitro using locally available fungicides. Four hundred fifty seeds of each cultivar of cowpea were disinfected with 2% sodium hypochlorite solution for 10 min and washed three times with sterile distilled water before placing them in PDA plates (5 seeds/9 cm Petri plate), incubated at 22±2o C for 12 hour each under continuous light and dark. A total of eight fungi were detected from seeds of cowpea. These were Aspergillus flavus, A. niger, Cylindrocarpon sp., Fusarium equisiti, F. oxyaporum, Penicillium chyrosogenum, Rhizopus oligosporus and R. stolonifer. Rhizopus spp. were dominant fungi recovered from seeds, followed by Penicillium, Aspergillus, Fusarium and Cylindrocarpon. The fungi detected resulted in decay and rotting of seeds, and thereby reducing percentage germination of seeds (22%, 37% and 63 % seed germination in Black eye, ER7 and Tswana varieties of cowpea respectively). Out of four fungicides tested, benlate, captan, dithane M 45 and chlorothalanil. Dithane M45 effectively controlled seed-borne fungi, and enhanced seed germination to an average of 86% (93% germination with no fungi detected in Tswana variety) as compared to chlorothalonile (79%), benlate and captan (77%) and un-treated seeds (45%). The fungal incidence was reduced to 2.3%, 4.3%, 5.3% and 5.3% when seeds were treated with dithane M-45, chlorothalonil, benlate and captan respectively as compared to 62% in non-treated seeds.

NITROGEN TRANSFORMATIONS NEAR UREA IN SOIL WITH DIFFERENT WATER POTENTIALS

1988 ◽  
Vol 68 (3) ◽  
pp. 569-576 ◽  
Author(s):  
YADVINDER SINGH ◽  
E. G. BEAUCHAMP
Keyword(s):  
Water Potential ◽  
Soil Water ◽  
Incubation Period ◽  
Relative Rate ◽  
Soil Water Potential ◽  
Nitrification Inhibitor ◽  
Silt Loam ◽  
Nitrogen Transformations ◽  
Water Potentials ◽  
Initial Soil

Two laboratory incubation experiments were conducted to determine the effect of initial soil water potential on the transformation of urea in large granules to nitrite and nitrate. In the first experiment two soils varying in initial soil water potentials (− 70 and − 140 kPa) were incubated with 2 g urea granules with and without a nitrification inhibitor (dicyandiamide) at 15 °C for 35 d. Only a trace of [Formula: see text] accumulated in a Brookston clay (pH 6.0) during the transformation of urea in 2 g granules. Accumulation of [Formula: see text] was also small (4–6 μg N g−1) in Conestogo silt loam (pH 7.6). Incorporation of dicyandiamide (DCD) into the urea granule at 50 g kg−1 urea significantly reduced the accumulation of [Formula: see text] in this soil. The relative rate of nitrification in the absence of DCD at −140 kPa water potential was 63.5% of that at −70 kPa (average of two soils). DCD reduced the nitrification of urea in 2 g granules by 85% during the 35-d period. In the second experiment a uniform layer of 2 g urea was placed in the center of 20-cm-long cores of Conestogo silt loam with three initial water potentials (−35, −60 and −120 kPa) and the soil was incubated at 15 °C for 45 d. The rate of urea hydrolysis was lowest at −120 kPa and greatest at −35 kPa. Soil pH in the vicinity of the urea layer increased from 7.6 to 9.1 and [Formula: see text] concentration was greater than 3000 μg g−1 soil. There were no significant differences in pH or [Formula: see text] concentration with the three soil water potential treatments at the 10th day of the incubation period. But, in the latter part of the incubation period, pH and [Formula: see text] concentration decreased with increasing soil water potential due to a higher rate of nitrification. Diffusion of various N species including [Formula: see text] was probably greater with the highest water potential treatment. Only small quantities of [Formula: see text] accumulated during nitrification of urea – N. Nitrification of urea increased with increasing water potential. After 35 d of incubation, 19.3, 15.4 and 8.9% of the applied urea had apparently nitrified at −35, −60 and −120 kPa, respectively. Nitrifier activity was completely inhibited in the 0- to 2-cm zone near the urea layer for 35 days. Nitrifier activity increased from an initial level of 8.5 to 73 μg [Formula: see text] in the 3- to 7-cm zone over the 35-d period. Nitrifier activity also increased with increasing soil water potential. Key words: Urea transformation, nitrification, water potential, large granules, nitrifier activity, [Formula: see text] production

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