A Correlative Study of Sunflower Seed Vigor Components as Related to Genetic Background

Seed vigor is an important trait that determines seed performance in the field, which corresponds to seed germination rate and seedling establishment. Previous works brought helpful equations to calculate several parameters allowing vigor characterization. In this work we used base water potential (Ψb), base temperature (Tb) and seed lot (Ki) constants to characterize the vigor of 44 sunflower seed lots. Contrasting responses to water or temperature stress and storage potential were recorded within this population, the most interesting being the opposite responses between Ψb and Ki. The genotypes that were resistant to water stress presented low ability for storage and vice versa. Furthermore, Ψb and Ki presented narrow ranges while Tb showed important variability within the 44 genotypes. The analysis of the whole dataset showed that these constants are not correlated to each other or to the seed size, suggesting that genetic background is the most important determining factor in seed performance. Consequently, vigor characterization of genotypes is needed in the crop selection process in order to optimize agricultural productivity.

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Hydropriming accelerates seed germination of Medicago sativa under stressful conditions: A thermal and hydrotime model approach

Legume Research - An International Journal ◽

10.18805/lr.v0i0.8404 ◽

2017 ◽

Author(s):

Rong Li ◽

Dandan Min ◽

Lijun Chen ◽

Chunyang Chen ◽

Xiaowen Hu

Keyword(s):

Water Potential ◽

Germination Rate ◽

High Water ◽

Nacl Stress ◽

Base Temperature ◽

Severe Water Stress ◽

Hydrotime Model ◽

Response To Temperature ◽

Base Water Potential ◽

Temperature Water

This study determined the effects of priming on germination in response to temperature, water potential and NaCl. Thermal and hydrotime models were utilized to evaluate changes in parameters of the model after priming. Priming reduced the amount of thermal time in both cultivars, but slightly increased the base temperature for germination from 1.0 to 3.5°C in “Longdong”. Priming significantly increased germination rate at high water potential but had no effect at low water potential. Further, priming reduced the hydrotime constant but made the median base water potential value slightly more positive in both cultivars. Thus, priming increased germination rate in water but decrease it under severe water stress. Germination rate was significantly increased in both cultivars under salinity (NaCl) stress. Moreover, priming improved seedling growth in response to temperature, water and salinity stress in both cultivars.

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Germination response of Hylocereus setaceus (Salm-Dyck ex DC: ) Ralf Bauer (Cactaceae) seeds to temperature and reduced water potentials

Brazilian Journal of Biology ◽

10.1590/s1519-69842010000100019 ◽

2010 ◽

Vol 70 (1) ◽

pp. 135-144 ◽

Cited By ~ 8

Author(s):

E. Simão ◽

M. Takaki ◽

VJM. Cardoso

Keyword(s):

Water Potential ◽

Germination Rate ◽

Base Temperature ◽

Temperature Range ◽

Water Potentials ◽

Germination Response ◽

Wide Range ◽

Optimum Interval ◽

Time Courses ◽

Base Water Potential

The germination response of Hylocereus setaceus seeds to isothermic incubation at different water potentials was analysed by using the thermal time and hydrotime models, aiming to describe some germination parameters of the population and to test the validity of the models to describe the response of the seeds to temperature and water potential. Hylocereus setaceus seeds germinated relatively well in a wide range of temperatures and the germination was rate limited from 11 to 20 °C interval and beyond 30 °C until 40 °C, in which the germination rate respectively shifts positively and negatively with temperature. The minimum or base temperature (Tb) for the germination of H. setaceus was 7 °C, and the ceiling temperature varied nearly from 43.5 to 59 °C depending on the percent fraction, with median set on 49.8 °C. The number of degrees day necessary for 50% of the seeds to germinate in the infra-optimum temperature range was 39.3 °C day, whereas at the supra-optimum interval the value of θ = 77 was assumed to be constant throughout. Germination was sensitive to decreasing values of ψ in the medium, and both the germinability and the germination rate shift negatively with the reduction of ψ, but the rate of reduction changed with temperature. The values of base water potential (ψb) shift to zero with increasing temperatures and such variation reflects in the relatively greater effect of low ψ on germination in supra optimum range of T. In general, the model described better the germination time courses at lower than at higher water potentials. The analysis also suggest that Tb may not be independent of ψ and that ψb(g) may change as a function of temperature at the infra-otimum temperature range.

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Calculating "Hydrothermal time" to quantify seed germination of tall fescue

Journal of New Zealand Grasslands ◽

10.33584/jnzg.2016.78.499 ◽

2016 ◽

Vol 78 ◽

pp. 163-168 ◽

Cited By ~ 3

Author(s):

S. Sharifiamina ◽

D.J. Moot ◽

M. Bloomberg

Keyword(s):

Water Potential ◽

Tall Fescue ◽

Festuca Arundinacea ◽

Germination Rate ◽

Base Temperature ◽

Hydrothermal Time ◽

Effects Of Temperature ◽

Moisture Conditions ◽

Base Water Potential ◽

Moderate Stress

The objective of this study was to quantify the combined effects of temperature and moisture on germination of tall fescue seed. Seeds were incubated for up to 50 days at a range of constant temperatures (5-35ºC) and germinated at five water potentials (0, -0.18, -0.37, -0.63 and -0.95 MPa). The maximum final germination percentages were 94 to 98 at 15-30ºC when water was not limited (0 MPa). Germination rate increased linearly from 5 to 27.5ºC, and then decreased linearly from 27.5 to 32.5ºC. Extrapolation of the sub-optimal temperatures identified a base temperature of 3.5 ± 0.5ºC and an optimum temperature of 27.5ºC. More negative water potential indicative of drier conditions, delayed germination and reduced germination rate. The average base water potential was -0.95 MPa at the suboptimal range of temperatures. An optimum range of germination (80-100%) occurred when temperatures were between 10 and 30ºC and water potential was between 0 to -0.37 MPa (moderate stress). These results provide a matrix of soil temperature and moisture conditions that are expected to result in successful germination and therefore provide the maximum opportunity for emergence of tall fescue seedlings. Keywords: Festuca arundinacea, 'Finesse Q', hydrothermal time

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The G-Protein α-Subunit GasC Plays a Major Role in Germination in the Dimorphic FungusPenicillium marneffei

Genetics ◽

10.1093/genetics/164.2.487 ◽

2003 ◽

Vol 164 (2) ◽

pp. 487-499 ◽

Cited By ~ 2

Author(s):

Sophie Zuber ◽

Michael J Hynes ◽

Alex Andrianopoulos

Keyword(s):

G Protein ◽

Germination Rate ◽

Yeast Cells ◽

Class Iii ◽

Temperature Dependent ◽

Gene Encoding ◽

Α Subunit ◽

G Protein Α Subunit ◽

Opportunistic Human Pathogen

AbstractThe opportunistic human pathogen Penicillium marneffei exhibits a temperature-dependent dimorphic switch. At 25°, multinucleate, septate hyphae that can undergo differentiation to produce asexual spores (conidia) are produced. At 37° hyphae undergo arthroconidiation to produce uninucleate yeast cells that divide by fission. This work describes the cloning of the P. marneffei gasC gene encoding a G-protein α-subunit that shows high homology to members of the class III fungal Gα-subunits. Characterization of a ΔgasC mutant and strains carrying a dominant-activating gasCG45R or a dominant-interfering gasCG207R allele show that GasC is a crucial regulator of germination. A ΔgasC mutant is severely delayed in germination, whereas strains carrying a dominant-activating gasCG45R allele show a significantly accelerated germination rate. Additionally, GasC signaling positively affects the production of the red pigment by P. marneffei at 25° and negatively affects the onset of conidiation and the conidial yield, showing that GasC function overlaps with functions of the previously described Gα-subunit GasA. In contrast to the S. cerevisiae ortholog Gpa2, our data indicate that GasC is not involved in carbon or nitrogen source sensing and plays no major role in either hyphal or yeast growth or in the switch between these two forms.

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Identification and Characterization of Novel Maize Mirnas Involved in Different Genetic Background

International Journal of Biological Sciences ◽

10.7150/ijbs.11619 ◽

2015 ◽

Vol 11 (7) ◽

pp. 781-793 ◽

Cited By ~ 10

Author(s):

Lei Sheng ◽

Wenbo Chai ◽

Xuefeng Gong ◽

Lingyan Zhou ◽

Ronghao Cai ◽

...

Keyword(s):

Genetic Background ◽

Different Genetic Background ◽

Identification And Characterization

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Characterization of a sunflower seed albumin which associates with oil bodies

Plant Science ◽

10.1016/0168-9452(96)04429-9 ◽

1996 ◽

Vol 118 (2) ◽

pp. 119-125 ◽

Cited By ~ 12

Author(s):

Patrick J.E. Thoyts ◽

Johnathan A. Napier ◽

Mark Millichip ◽

A.Keith Stobart ◽

W.Trevor Griffiths ◽

...

Keyword(s):

Sunflower Seed ◽

Oil Bodies

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High gamma irradiation doses and long storage times reduce soybean seed quality

Semina Ciências Agrárias ◽

10.5433/1679-0359.2016v37n3p1219 ◽

2016 ◽

Vol 37 (3) ◽

pp. 1219

Author(s):

Danúbia Aparecida Costa Nobre ◽

Carlos Sigueyuki Sediyama ◽

Valter Arthur ◽

Newton Deniz Piovesan ◽

Alisson Santos Lopes da Silva

Keyword(s):

Gamma Irradiation ◽

Seed Quality ◽

Germination Rate ◽

Soybean Seed ◽

Response Surfaces ◽

Seed Vigor ◽

Production Cycle ◽

High Gamma ◽

Storage Times ◽

Long Storage

High quality seeds are required for soybean production. This study evaluated the effect of gamma irradiation and storage time on seed quality in soybean lines VX04-6828 and VX04-5692. Seeds were gamma irradiated (60Co) with 0, 50, 150, and 250 Gy. After the first seed production cycle (M1), the harvested seeds were stored in the laboratory for 0, 2, 4, and 6 months. Moisture content, seed quality (germination rate, dead seeds, and normal and abnormal seedlings), and seed vigor (first germination count, germination index, and seedling length) were determined. Data were submitted to analysis of variance for each soybean line using a 4 x 4 factorial design (four storage times x four gamma irradiation doses). Response surfaces were constructed based on the F test significance (p ? 0.05). VX04-5692 seeds were more sensitive to gamma radiation than were VX04-6828 seeds. Soybean seed quality was highest in M2 seeds derived from seeds irradiated with less than 100 Gy and stored for up to two months. High gamma irradiation doses and long storage times reduced soybean seed quality.

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Effects of seed priming treatments on the germination and development of two rapeseed (Brassica napus L.) varieties under the co-influence of low temperature and drought

PLoS ONE ◽

10.1371/journal.pone.0257236 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257236

Author(s):

Zong He Zhu ◽

Abdul Sami ◽

Qing Qing Xu ◽

Ling Ling Wu ◽

Wen Yin Zheng ◽

...

Keyword(s):

Low Temperature ◽

Germination Rate ◽

Seed Priming ◽

Seed Vigor ◽

Stress Conditions ◽

Stem Length ◽

Activity Levels ◽

Sod Activity ◽

Germination Time ◽

Rape Seedlings

The present study was performed to evaluate the effects of seed priming. This was done by soaking the seeds of two rapeseed cultivars, namely, ZY15 (tolerant to low temperature and drought) and HY49 (sensitive to low temperature and drought), for 12 h in varying solutions: distilled water, 138 mg/L salicylic acid (SA), 300 mg/L gibberellic acid (GA), 89.4 mg/L sodium nitroprusside (SNP), 3000 mg/L calcium chloride (CaCl2), and 30 mg/L abscisic acid (ABA). Primed and non-primed seeds were left to germinate at 15°C and -0.15 MPa (T15W15) and at 25°C and 0 MPa (T25W0), respectively. The results showed that SA, GA, SNP, CaCl2, and ABA significantly improved the germination potential (GP), germination rate (GR), germination index (GI), stem fresh weight (SFW), stem dry weight (SDW), root length (RL), stem length (SL), and seed vigor index (SVI) under T15W15. For ZY15 seeds under T25W0, GA, SNP, CaCl2, and ABA priming reduced the average germination time (96% after 5 days) compared to that of the control (88% after 5 days). For ZY15 seeds under T15W15, SA, SNP, CaCl2, and ABA priming, with respect to the control and water-treated groups, shortened the average germination time (92% after 5 days) compared to that of the control (80% after 5 days). For HY49 seeds under T25W0, GA, SNP, CaCl2, and ABA priming reduced the average germination time (92% after 5 days) compared to that of the control (85% after 5 days). Similarly, for HY49 seeds under T15W15, GA priming shortened the average germination time (89% after 5 days) compared to that of the control (83% after 5 days). These priming agents increased the net photosynthesis, stomatal conductivity, and transpiration rate of rape seedlings under conditions of low temperature and drought stress, while also decreasing intercellular carbon dioxide (CO2) concentrations. Additionally, SA, GA, SNP, CaCl2, and ABA increased superoxide dismutase concentrations (SOD) and ascorbic peroxidase (APX) activities of rape seedlings under stress conditions, while decreasing catalase (CAT) and peroxidase (POD) activities in ZY15 seedlings. In HY49, which is sensitive to low temperature and drought, all priming solutions, except for SNP, led to an increase in SOD activity levels and a decrease in CAT activity levels. Overall, SA, GA, SNP, and CaCl2 increased the concentrations of indoleacetic acid (IAA), GA, ABA, and cytokinin (CTK) in seedlings under stress conditions. Moreover, compared to SA, CaCl2, and ABA, GA (300 mg/L) and SNP (300 mol/L) showed improved priming effects for ZY15 and HY49 under stress conditions.

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Effects of Matric and Osmotic Priming Treatments on Broccoli Seed Germination

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.121.3.423 ◽

1996 ◽

Vol 121 (3) ◽

pp. 423-429 ◽

Cited By ~ 17

Author(s):

Lewis W. Jett ◽

Gregory E. Welbaum ◽

Ronald D. Morse

Keyword(s):

Polyethylene Glycol ◽

Seed Germination ◽

Root Growth ◽

Growth Rates ◽

Germination Rate ◽

Membrane Integrity ◽

Seed Vigor ◽

Radicle Emergence ◽

The Mean ◽

Peg 8000

Priming, a controlled-hydration treatment followed by redrying, improves the germination and emergence of seeds from many species. We compared osmotic and matric priming to determine which was the most effective treatment for improving broccoli seed germination and to gain a greater understanding of how seed vigor is enhanced by priming. Broccoli (Brassica oleracea L. var. italica) seeds were osmotically primed in polyethylene glycol (PEG 8000) at -1.1 MPa or matrically primed in a ratio of 1.0 g seed:0.8 g synthetic calcium silicate (Micro-Cel E):1.8 ml water at -1.2 MPa. In the laboratory, germination rates and root lengths were recorded from 5 to 42C and 10 to 35C, respectively. Broccoli seeds germinated poorly at >35C. Root growth after germination was more sensitive to temperatures >30C and <15C than radicle emergence. Matric and osmotic priming increased germination rate in the laboratory, greenhouse, and field. However, matric priming had a greater effect on germination and root growth rates from 15 to 30C. Neither priming treatment affected minimum or maximum germination or root growth temperatures. Both priming treatments decreased the mean thermal time for germination by >35%. The greater germination performance of matrically primed seeds was most likely the result of increased oxygen availability during priming, increased seed Ca content, or improved membrane integrity.

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Hydrotime model to evaluate the effects of a set of priming agents on seed germination of two leek cultivars under water stress

Seed Science and Technology ◽

10.15258/sst.2021.49.2.07 ◽

2021 ◽

Author(s):

Alessandro Romano ◽

Romana Bravi

Keyword(s):

Water Stress ◽

Water Deficit ◽

Germination Rate ◽

Intraspecific Variability ◽

Germination Percentage ◽

Allium Ampeloprasum ◽

Cultivated Species ◽

Hydrotime Model ◽

Base Water Potential ◽

Peg 8000

Water deficit is one of the main constraints of germination for many cultivated species. Among the techniques used to promote germination, seeds priming has been found to play a key role. In the present study, a set of different priming agents (KCl, KH2PO4, CaCl2 and PEG 8000) was tested on seeds of two leek (Allium ampeloprasum L.) cultivars (“Lungo della riviera” and “Monstrueux de Carentan”) to assess the effects on germination performances both in optimal hydration condition (Ψw = 0 MPa) and under water deficit (−0.3 and −0.6 MPa). Germination percentage of “Lungo della riviera” was improved by PEG and KCl at −0.3 MPa and −0.6 MPa, respectively, whereas CaCl2 improved germination of “Monstrueux de Carentan” at −0.6 MPa. Osmopriming was beneficial in terms of germination rate although to different extent depending on genotype and priming agent. The hydrotime model showed that the effects of priming on germination rate was mostly due to a lowering of the predicted hydrotime constant (θH), whereas median base water potential Ψb(50) tended to increase following treatments albeit with some exception. In this study, hydrotime model proved to be a useful tool to test the effectiveness of different priming treatments on leek seeds and the intraspecific variability in germination capability and speed under water stress.

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