scholarly journals Pericarp, Leachate, and Carbohydrate Involvement in Thermoinhibition of Germinating Spinach Seeds

1999 ◽  
Vol 124 (3) ◽  
pp. 301-306 ◽  
Author(s):  
Daniel I. Leskovar ◽  
Virgil Esensee ◽  
Helen Belefant-Miller
Keyword(s):  
Seed Germination ◽  
Constant Temperature ◽  
Spinacia Oleracea ◽  
Germination Percentage ◽  
Germination Inhibition ◽  
Physical Barrier ◽  
Glucose Levels ◽  
Incubation Temperatures ◽  
Aba Content ◽  
Genotype Sensitivity

Spinach (Spinacia oleracea L.) seed germination can be inhibited by high temperatures. An understanding of thermoinhibition in spinach is critical in predicting germination and emergence events. The purpose of this study was 3-fold: 1) to determine seed germination percentage and rate of spinach genotypes—`Cascade', `ACX 5044', `Fall Green', and `ARK 88-354'—exposed to constant and alternating temperatures; 2) to determine the nature and extent of inhibition imposed by the pericarp; and 3) to investigate leachate and oligosaccharide involvement in thermoinhibition. Germination inhibition began at >20 °C constant temperature and was totally suppressed at 35 °C. Alternating temperatures at 30/15 °C (12-hour day/12-hour night) resulted in greater germination than a constant 30 °C. The genotype sensitivity to supraoptimal temperatures was in the order of `ARK 88-354' ≤ `Fall Green' < `ACX 5044' < `Cascade', but the highly thermoinhibited `Cascade' seeds retained the ability to germinate when shifted to lower incubation temperatures. The pericarp inhibited germination, since seeds deprived of the pericarp had ≈90% germination at 30 °C. `ACX 5044' and `Cascade' had higher ABA content in the pericarp than `ARK 88-354' and `Fall Green'. Before imbibition at 30 °C, raffinose levels in each genotype were in the order of `ARK 88-354' > `Fall Green' > `Cascade'. After 48 hours of imbibition, sucrose and glucose levels were highest and raffinose levels were lowest in `ARK 88-354' and `Fall Green' seeds, while `Cascade' seeds remained less active metabolically. These data suggest that the pericarp apparently acts as a physical barrier as well as a source of inhibitors during thermoinhibition.

The influence of diffused light and temperature on seed germination of three genetically nondormant lines of wild oats (Avena fatua) and its adaptive significance

1986 ◽  
Vol 64 (9) ◽  
pp. 1910-1915 ◽  
Author(s):  
Ramma Sawhney ◽  
Andrew I. Hsiao ◽  
William A. Quick
Keyword(s):  
Seed Germination ◽  
Light Intensity ◽  
Adaptive Significance ◽  
Avena Fatua ◽  
Wild Oat ◽  
Germination Inhibition ◽  
Wild Oats ◽  
Two Factors ◽  
Incubation Temperatures ◽  
Diffused Light

Freshly harvested seeds of three genetically nondormant populations of wild oat (Avena fatua L.) germinated readily in the dark at optimum temperatures. Direct or diffused light caused germination inhibition in seeds of all these populations. This light-induced germination inhibition was intensity dependent; the higher the light intensity, the greater the inhibition. Germination inhibition by light was accentuated by higher incubation temperatures, indicating an interaction between these two factors on the induction of secondary seed dormancy in genetically nondormant populations. This interaction may be of adaptive significance to the survival of nondormant populations, and reconciles some apparently conflicting reports in the literature.

scholarly journals Effect of Temperature on Seed Germination in Spinach (Spinacia oleracea)

HortScience ◽  
2016 ◽  
Vol 51 (12) ◽  
pp. 1475-1478 ◽  
Author(s):  
Jessica Chitwood ◽  
Ainong Shi ◽  
Michael Evans ◽  
Curt Rom ◽  
Edward E. Gbur ◽  
...  
Keyword(s):  
Seed Germination ◽  
Heat Tolerance ◽  
Spinacia Oleracea ◽  
Early Stage ◽  
Germination Percentage ◽  
Effect Of Temperature ◽  
Randomized Design ◽  
Heat Tolerant ◽  
Completely Randomized Design ◽  
Germination Experiment

Breeding heat-tolerant spinach is an important project to meet the demand of increasing spinach production in heat conditions. Seed germination is the early stage to test, screen, and develop heat-tolerant spinach genotypes. The objective of this research was to determine temperature effect on the seed germination percentage and to select heat-tolerant spinach genotypes. A total of nine spinach genotypes were used in this research. The germination experiment was conducted using seven temperatures: 10, 15, 20, 25, 30, 32, and 35 °C under growth chambers. The temperature trials were conducted using completely randomized design (CRD) with three replicates. Spinach seed germination percentage varied among the nine spinach genotypes under the seven temperatures, indicating that genetic variation for heat tolerance existed in the nine spinach genotypes. ‘Donkey’, ‘Marabu’, and ‘Raccoon’ showed higher seed germination percentage with over 70% at 30 and 32 °C, indicating the three spinach genotypes had heat tolerance for germination. However, all spinach genotypes except ‘Ozarka II’ dropped their germination percentages sharply to less than 30%; ‘Ozarka II’ had 63% germination under 35 °C, indicating it is a good source of heat tolerance for seed germination. The higher germination percentages above 30 °C of ‘Ozarka II’, ‘Donkey’, ‘Marabu’, and ‘Raccoon’ may indicate their potential as donors of heat-tolerant traits in spinach breeding program.

scholarly journals Germination Behaviour of Pea Seeds on Municipality Sewage and Some Industrial Effluents of Biratnagar

Our Nature ◽  
1970 ◽  
Vol 1 (1) ◽  
pp. 33-36 ◽  
Author(s):  
Mohan Kumar Shrestha ◽  
Bhabindra Niroula
Keyword(s):  
Seed Germination ◽  
Industrial Effluents ◽  
Inhibitory Effect ◽  
Germination Percentage ◽  
Dairy Farming ◽  
Sewage Effluent ◽  
Germination Inhibition ◽  
Pisum Sativum L ◽  
Germination Behaviour ◽  
Pea Seeds

Municipality sewage and effluents from Dairy Farming and Shah Udyog were chosen to assess the germination activity of Pea (Pisum sativum L. var. arkel). The effluents from Municipality Sewage and Dairy Farming inhibited seed germination while Shah Udyog effluent promoted. The effluent from Municipality Sewage and Dairy Farming delayed seed germination during early hours i.e., 24 hours of sowing. The inhibition was maximum in the Municipality Sewage effluent where as the germination percentage never exceeded 48% even after 120 hours of sowing. The dilution experiment revealed that the effluent of Municipality Sewage was still inhibitory upto 25% (v/v) concentration while the inhibitory effect of Dairy Farming was overcome at 50% (v/v) concentration. The Shah Udyog effluent was safe for seed germination at all dilution. Keywords: Effluent, Seed Germination, Inhibition and Promotiondoi:10.3126/on.v1i1.302Our Nature (2003) 1: 33-36

Assessing tree germination resilience to global warming: a manipulative experiment using sugar maple (Acer saccharum)

2016 ◽  
Vol 26 (2) ◽  
pp. 153-164 ◽  
Author(s):  
Kevin A. Solarik ◽  
Dominique Gravel ◽  
Aitor Ameztegui ◽  
Yves Bergeron ◽  
Christian Messier
Keyword(s):  
Seed Germination ◽  
Constant Temperature ◽  
Climate Warming ◽  
Acer Saccharum ◽  
Sugar Maple ◽  
Incubation Temperature ◽  
Germination Percentage ◽  
Seed Sources ◽  
Seed Origin ◽  
Maple Seed

AbstractA climate warming of 2–5°C by the end of the century will impact the likelihood of seed germination of sugar maple (Acer saccharum), a dominant tree species which possesses a restricted temperature range to ensure successful reproduction. We hypothesize that seed origin affects germination due to the species' local adaptation to temperature. We tested this by experimentally investigating the effect of incubation temperature and temperature shifting on sugar maple seed germination from seven different seed sources representing the current species range. Survival analysis showed that seeds from the northern range had the highest germination percentage, while the southern range had the lowest. The mean germination percentage under constant temperatures was best when temperatures were ≤5°C, whereas germination percentages plummeted at temperatures ≥11°C (5.8%). Cool shifting increased germination by 19.1% over constant temperature treatments and by 29.3% over warm shifting treatments. Both shifting treatments caused earlier germination relative to the constant temperature treatments. A climate warming of up to +5°C is shown to severely reduce germination of seeds from the southern range. However, under a more pronounced warming of 7°C, seed germination at the northern range become more affected and now comparable to those found from the southern range. This study states that the high seed germination percentage found in sugar maple at the northern range makes it fairly resilient to the warmest projected temperature increase for the next century. These findings provide forest managers with the necessary information to make accurate projections when considering strategies for future regeneration while also considering climate warming.

scholarly journals Effect of Potassium Nitrate Priming on Seed Germination of Seashore Paspalum

HortScience ◽  
2008 ◽  
Vol 43 (7) ◽  
pp. 2259-2262 ◽  
Author(s):  
Sang In Shim ◽  
Jun-Cheol Moon ◽  
Cheol Seong Jang ◽  
Paul Raymer ◽  
Wook Kim
Keyword(s):  
Seed Germination ◽  
Constant Temperature ◽  
Critical Factor ◽  
Potassium Nitrate ◽  
Germination Percentage ◽  
Seashore Paspalum ◽  
Second Stage ◽  
Priming Condition ◽  
Osmotic Solution ◽  
Alternating Temperature

Germination of seashore paspalum (Paspalum vaginatum Swartz) is a critical factor influencing seedling establishment when seeded directly in fields. In this research, pregermination priming with osmotic solution was used to improve the germination percentage of seashore paspalum. The goal of this study was to develop techniques that improve the germination of a seashore paspalum cultivar (SeaSpray). Seeds were subjected to priming in petri dishes with solutions of KNO3 at 25 °C for 24, 48, and 72 h in growth chambers. Germination percentage differed by priming duration as well as concentration of priming media. Based on the germination percentage 14 days after imbibition, the most promising priming condition was the treatment with 0.2% or 0.5% KNO3 for 72 h at a constant temperature of 30 °C and 0.2% or 0.5% KNO3 for 48 to 72 h at alternating temperature of 25/35 °C. Both concentrations showed reasonable germination percentage greater than 85% at alternating temperature condition. Priming with KNO3 solution for 48 to 72 h improved not only germination percentage, but also uniformity. The increased duration of priming with KNO3 was positively correlated with an improved germination percentage. The effect of increasing concentration was the most apparent at a constant temperature (30 °C) regime with the treatment of 0.2% KNO3 priming. Germination percentage was increased from 34.3% to 68.0% 2 weeks after imbibition (WAI) as the priming duration was increased from 24 to 72 h. Priming with KNO3 for 3 days also had a modest effect on germination percentage (greater than 74.7%) at 1 WAI. Therefore, priming with 0.2% or 0.5% solution of KNO3 for 72 h is a recommended method that can be practically applied for increasing germination of paspalum under an alternating temperature (25/35 °C) condition. The regression analysis between odds of germination percentage and germination time showed that priming treatment increased internal activities during the second stage of seed germination.

scholarly journals Effect of H2O-Based Low-Pressure Plasma (LPP) Treatment on the Germination of Bambara Groundnut Seeds

Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 338
Author(s):  
Naeem Ahmed ◽  
Asad Masood ◽  
Kim S. Siow ◽  
M. F. Mohd Razip Wee ◽  
Rahmat Zaki Auliya ◽  
...  
Keyword(s):  
Food Security ◽  
Seed Germination ◽  
Chemical Modification ◽  
Low Pressure ◽  
Germination Percentage ◽  
Bambara Groundnut ◽  
Pressure Plasma ◽  
Low Pressure Plasma ◽  
Amine Groups

In general, seed germination is improved by low-pressure plasma (LPP) treatment using precursors such as air, nitrogen, argon, or water (H2O). Here, H2O-based LPP treatment using the optimized parameters of 10 W and 10 s improves the germination of Bambara groundnut seeds by 22%. LPP increases the wettability and roughness of the seed hilum while oxidizing the surface with carboxyl and amine groups. In this H2O-based treatment of Bambara groundnut seeds, combinatory etching and chemical modification facilitated the imbibition process and increased the germination percentage. The success of this method has the potential to be scaled up to solve food security with seeds otherwise facing germination-related issues.

scholarly journals Asymbiotic germination of Vanilla planifolia in relation to the timing of seed collection and seed pretreatments

2021 ◽  
Vol 62 (1) ◽  
Author(s):  
Chih-Hsin Yeh ◽  
Kai-Yi Chen ◽  
Yung-I. Lee
Keyword(s):  
Seed Germination ◽  
Seed Development ◽  
Seed Coat ◽  
Germination Percentage ◽  
Vanilla Planifolia ◽  
Outermost Layer ◽  
Seed Collection ◽  
Seed Pretreatment ◽  
Immature Seeds ◽  
Mature Seeds

Abstract Background Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, propagation with seed germination of V. planifolia is intricate and unstable because the seed coat is extremely hard with strong hydrophobic nature. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla. Results We found that soaking mature seeds in 4% sodium hypochlorite solution from 75 to 90 min significantly increased germination. For the culture of immature seeds, the seed collection at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. Seeds at 60 DAP and subsequent stages germinated poorly. As the seed approached maturity, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope at maturity. On toluidine blue O staining, the wall of outer seed coat stained greenish blue, indicating the presence of phenolic compounds. As well, on Nile red staining, a cuticular substance was detected in the surface wall of the embryo proper and the innermost wall of the inner seed coat. Conclusion We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The window for successful germination of culturing immature seed was short. The quick accumulation of lignin, phenolics and/or phytomelanins in the seed coat may seriously inhibit seed germination after 45 DAP. As seeds matured, the thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, which may play an important role in inducing dormancy. Further studies covering different maturity of green capsules are required to understand the optimal seed maturity and germination of seeds.

scholarly journals Effect of Environmental Factors on the Germination and Emergence of Drunken Horse Grass (Achnatherum inebrians)

Weed Science ◽  
2020 ◽  
pp. 1-29
Author(s):  
Yonghuan Yue ◽  
Guili Jin ◽  
Weihua Lu ◽  
Ke Gong ◽  
Wanqiang Han ◽  
...  
Keyword(s):  
Seed Germination ◽  
Environmental Factors ◽  
Abiotic Factors ◽  
Seedling Emergence ◽  
Management Strategies ◽  
Germination Percentage ◽  
Western China ◽  
Burial Depth ◽  
Achnatherum Inebrians ◽  
Water Ph

Abstract Drunken horse grass [Achnatherum inebrians (Hance) Keng] is a perennial poisonous weed in western China. A comprehensive understanding of the ecological response of A. inebrians germination to environmental factors would facilitate the formulation of better management strategies for this weed. Experiments were conducted under laboratory conditions to assess the effects of various abiotic factors, including temperature, light, water, pH and burial depth, on the seed germination and seedling emergence of A. inebrians. The seeds germinated at constant temperatures of 15, 20, 25, 30, 35°C and in alternating-temperature regimes of 15/5, 20/10, 25/15, 30/20, 35/25, 40/30°C, and the seed germination percentages under constant and alternating temperatures ranged from 51% to 94% and 15% to 93%, respectively. Maximum germination occurred at a constant temperature of 25°C, and germination was prevented at 45/35°C. Light did not appear to affect seed germination. The germination percentage of seeds was more than 75% in the pH range of 5 to 10, with the highest germination percentage at pH 6. The seeds germinated at osmotic potentials of 0 MPa to -1.0 MPa, but decreasing osmotic potential inhibited germination, with no germination at -1.2MPa. After 21 d of low osmotic stress, the seeds that did not germinate after rehydration had not lost their vitality. The seedling emergence percentage was highest (90%) when seeds were buried at 1 cm but declined with increasing burial depth and no emergence at 9 cm. Deep tillage may be effective in limiting the seed germination and emergence of this species. The results of this study provide useful information on the conditions necessary for A. inebrians germination and provide a theoretical basis for science-based prediction, prevention and control of this species.

The Effect of High Concentrations of Ethylene on Seed Germination of Douglas Fir (Pseudotsugamenziesii (Mirb.) Franco)

1975 ◽  
Vol 5 (3) ◽  
pp. 419-423 ◽  
Author(s):  
Carey Borno ◽  
Iain E. P. Taylor
Keyword(s):  
Seed Germination ◽  
Germination Rate ◽  
Inhibitory Effect ◽  
Germination Percentage ◽  
Douglas Fir ◽  
Control Treatment ◽  
Continuous Exposure ◽  
Short Term ◽  
Short Term Exposure ◽  
High Concentrations

Stratified, imbibed Douglas fir (Pseudotsugamenziesii (Mirb.) Franco) seeds were exposed to 100% ethylene for times between 0 and 366 h. Germination rate and germination percentage were increased by treatments up to 48 h. The 12-h treatment gave largest stimulation; 30% enhancement of final germination percentage over control. Treatment for 96 h caused increased germination rate for the first 5 days but reduced the germination percentage. Germinants were subject to continuous exposure to atmospheres containing 0.1 – 200 000 ppm ethylene in air, but it did not stimulate growth, and the gas was inhibitory above 100 ppm. Although some effects of high concentrations of ethylene may have been due to the lowering of oxygen supplies, this alone was insufficient to account for the full inhibitory effect. The mechanism of stimulation by short-term exposure to ethylene is discussed.

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