• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.139-143
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• 1983

Nicotiana Tabacum L., cv. NC2326, Burley2l and Sohyang seeds were coated with different five materials - zeolite, serpentine, coal briquet ash, serpentine+zeolite and coal briquet ash+zeolite - to investigate the effects of coating on germination. The coating materials had different characteristics and gave varied effects on germination. Among three tobacco varieties, coated seeds of Burley2l showed the most sensitive responses in germination rate of decreasing and delaying at low temperature on seedbed and laboratory tests.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.215-219
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• 2003

To investigate the effects of low dose gamma radiation and seed moisture content (SMC) on germination and early growth of vegetable crops, seeds of chinese cabbage (Brassica campestris L.), radish (Raphanus sativus L.), red pepper (Capcicum annuum L.), figleaf gourd (Cucurbita ficifolia Bouche) and bottle gourd (Lagenaria siceraria Standl), with different SMC were irradiated with different doses ($0{\sim}20\;Gy$) of gamma-ray by irradiator ($^{60}Co$, ca.150 TBq of capacity, AECL). Vegetable crops in which low dose gamma radiation was irradiated in seeds with different moisture content showed different response in seed germination and early growth to low dose gamma radiation. The germination rate of chinese cabbage, figleaf ground and bottle gourd irradiated with $2{\sim}8\;Gy$ showed interactive responses against relative SMC. Also, significant interactions occurred for the early growth between those factors. The stimulating effects of gamma radiation were more pronounced for hydrated seeds of chinese cabbage, radish, figleaf gourd and bottle gourd showing prominent responses with $2{\sim}10\;Gy$ irradiation, particularly for chinese cabbage and bottle gourd. These results suggest that radiation may promote germination and early growth of vegetable crops through interaction with SMC.

• Molecules and Cells
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• v.40 no.8
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• pp.577-586
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• 2017

Phytocystatins (PhyCYSs) are plant-specific proteinaceous inhibitors that are implicated in protein turnover and stress responses. Here, we characterized a PhyCYS from Arabidopsis thaliana, which was designated AtCYS5. RT-qPCR analysis showed that the expression of AtCYS5 in germinating seeds was induced by heat stress (HS) and exogenous abscisic acid (ABA) treatment. Analysis of the expression of the ${\beta}-glucuronidase$ reporter gene under the control of the AtCYS5 promoter showed that AtCYS5 expression during seed germination was induced by HS and ABA. Constitutive overexpression of AtCYS5 driven by the cauliflower mosaic virus 35S promoter led to enhanced HS tolerance in transgenic Arabidopsis, which was characterized by higher fresh weight and root length compared to wild-type (WT) and knockout (cys5) plants grown under HS conditions. The HS tolerance of AtCYS5-overexpressing transgenic plants was associated with increased insensitivity to exogenous ABA during both seed germination and post-germination compared to WT and cys5. Although no HS elements were identified in the 5'-flanking region of AtCYS5, canonical ABA-responsive elements (ABREs) were detected. AtCYS5 was upregulated in ABAtreated protoplasts transiently co-expressing this gene and genes encoding bZIP ABRE-binding factors (ABFs and AREB3). In the absence of ABA, ABF1 and ABF3 directly bound to the ABREs in the AtCYS5 promoter, which activated the transcription of this gene in the presence of ABA. These results suggest that an ABA-dependent pathway plays a positive role in the HS-responsive expression of AtCYS5 during seed germination and post-germination growth.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.12-18
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• 1987

Seed dormancy and germination responses to light and gases were determined for Echinochloa colona (L.) Link. E. colons seeds did not require a period of after-ripening for breaking dormancy. Water movement occurred readily across the seed coat. Repeated cycles of hydration and dehydration reduced viability and thence germination. Water imbibition for 24 h increased seed moisture by 21%; seeds returned to their original weight after drying at room temperature for 13 h. Removal of seed-coats increased germination in the dark. Light stimulated germination. Germination at a daylight intensity of 51.9 $Wm^{-2}$ or less was significantly reduced. Germination of seeds which were exposed to light for 1 h each day was significantly less than that of seeds exposed for longer than 2 h a day. Seeds subjected to blue light had delayed and decreased germination compared to seeds exposed to red light. Ethylene or carbon dioxide exogenenously added in the presence of light stimulated germination. The addition of the two gases together had a synergistic effect. In the dark, however, the two gases did not increase germination.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.576-581
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• 2008

The germination responses of Fraxinus rhynchophylla seeds collected from four provenances to constant temperature were investigated over the range $5{\sim}35^{\circ}C$. Difference among seeds in percentage and rate of germination and cardinal temperatures was observed. The seeds from Inje had high germination percentage at low temperature ($5{\sim}15^{\circ}C$) whereas those from Gangneung had high germination percentage at high temperature ($30{\sim}35^{\circ}C$). Three cardinal temperatures viz., the base ($T_b$), the maximum ($T_m$) and the optimum ($T_o$) for germination percentage and germination rate varied among four provenances. $T_b$, $T_m$ and $T_o$ for F. rhynchophylla seed germination as estimated by the quadratic models were the lowest in Inje while those were the highest in Gangneung. The cardinal temperatures ($T_b$, $T_m$ and $T_o$) were estimated by linear sub- and supra-optimal models for germination rate as a function of temperature response. $T_b$ was the lowest in Hoengseong while that was the highest in Gangneung. $T_m$ and $T_o$ were the lowest in Inje while those were also the highest in Gangneung. That is, the seeds from the provenance where the annual mean temperature was high had the higher cardinal temperatures ($T_b$, $T_m$ and $T_o$) as compared to seeds from the provenance where the annual mean temperature was low.

• Korean Journal of Weed Science
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• v.16 no.2
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• pp.114-121
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• 1996

This study was conducted to investigate seed germination, seedling growth, and responses to herbicides of Bidens tripartita L. When the field-collected seeds were stored under a dry-room temperature, dry-low temperature, wet-low temperature, or dry-high temperature condition, no seeds were germinated in a growth chamber with 14 hr photoperiod up to 35 days after the storage. Exceptionally, however, some seeds stored under a wet-room temperature condition were germinated after 25 days of the storage. This might be due to the fact that the seed coats were damaged by fungi which developed during the storage. Seeds stored under a wet-low temperature condition (stratification) began to be germinated after 3 months of the storage and the germination rate increased with a prolonged stratification. Almost all seeds were germinated after 9 months of the stratification. These results suggest that the dormancy of B. tripartita L. seeds relate to the seed coat and thus several attempts were made to induce seed germination through damaging or weakening the seed coat. Freezing($-20^{\circ}C$), drying($100^{\circ}C$), or swelling($40^{\circ}C$) of the seeds was not effective to induce the germination. Treatments of concentrated sulfuric acid, $KNO_3$, or gibberellin to the seeds had no effect on inducing the germination. However, ethrel had a stimulatory effect on the germination of the seeds with an optimum concentration of 250ppm. A seed cutting was also effective to induce the germination, but seedlings from the seeds had cutted cotyledons. Germination of the stratified seeds varied with the temperature condition to which they were subjected, but not with light. The germination rate was the highest at 35 - $40^{\circ}C$. Although the seeds were not able to germinate under a submerged condition, seedlings after 2-leaf-stage exhibited better growth under a submerged or a subirrigated condition than under an upland condition. Among the herbicides tested, pyrazosulfuton-ethyl, linuron, and bentazone were found to be effective for controlling B. tripartita L., having more herbicidal effect with an earlier application.

• Proceedings of the Korean Society of Potoscience Conference
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• spring
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• pp.97-103
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• 2003

Phytochrome controls diverse aspects of plant development in response to the ambient light conditions. HFRl, a basic helix-loop-helix protein, is required for a subset of phytochrome A (phy A)-mediated photo-responses in Arabidopsis. Here, we show that overexpression of HFR1-N105, but not the one of the full-length HFR1, confers exaggerated photo-responses. The transgenic plants overexpressing HFR1- N105 exhibited light-independence in a subset of photo-responses, including germination, de-etiolation, gravitropic hypocotyl growth, and blocking of greening. Overexpression of HFR1-N105 also caused constitutive light-responses in the expression of some light-regulated genes. In addition, the HFR1-N105 overexpressor showed hypersensitive responses under R and FR light, dependently on phyB and phyA, respectively. End-of-day far-red light response and petiole elongation were suppressed in the HFR1-N105 overexpressor plants. Together these results imply that overexpression of HFR1-N105 activated a branch of light signaling, supporting the hypothesis that transcriptional regulation in the nucleus would be the primary mechanism of light signaling in Arabidopsis. We discuss the biotechnological potential of the mutant bHLH protein, HFR1-N105 in regard to suppressed shade avoidance syndrome.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.132-132
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• 2022

The application of direct seeding cultivation reduces time, labor, and cost. However, this application often has poor seedling establishment and leads to lower yield as compared to transplanting system. The tolerance to anaerobic and low temperature germination is important to improve seedling establishment and the wide-spread application of direct seeding method. This study was carried out to evaluate the responses of three japonica cultivars to different temperatures (15℃, 18℃, 21℃, 24℃, and 27℃) and different flooding levels (1 cm, 4 cm, 7 cm, 10 cm) during germination and seedling development. The mean survival percentage significantly increased (P<0.05) when the flooding level decreased and when temperature increased. There were significant effects of the interaction between temperature and water depth on survival percentage and seedling height. When temperature decreased from 27℃ to 15℃, the germination duration significantly increased from 6.4 days to 16.3 days while the germination speed, survival percentage, and seedling height decreased from 5.3 seeds day^-1, 61.9% and 190.6 cm to 2.2 seeds day^-1, 33.2%, and 47 cm, respectively. The increase in temperature under submergence condition was associated with the increased expression of Amy3D and ALDH2a but the decreased expression of ADH1 and PDC1. The results of this research would be used for further studies and breeding programs to improve rice seedling establishment and the application of direct seeding cultivation.

• Korean Journal of Ecology and Environment
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• v.52 no.3
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• pp.210-220
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• 2019

Population growth and the increase of energy consumption due to civilization caused global warming. Temperature on the Earth rose about $0.7^{\circ}C$ for the last 100 years, the rate is accelerated since 2000. Temperature is a factor, which determines physiological action, growth and development, survival, etc. of the plant together with light intensity and precipitation. Therefore, it is expected that global warming would affect broadly geographic distribution of the plant as well as structure and function ecosystem. In order to understand the effect of global warming on the ecosystem, a study about the effect of temperature rise on germination and growth in the plant is required necessarily. This study was carried out to investigate the effects of experimental warming on the germination and growth of two oak species(Quercus mongolica and Q. serrata) in temperature gradient chamber(TGC). This study was conducted in control, medium warming treatment($+1.7^{\circ}C$; Tm), and high warming treatment ($+3.2^{\circ}C$; Th) conditions. The final germination percentage, mean germination time and germination rate of two oak species increased by the warming treatment, and the increase in Q. serrata was higher than that in Q. mongolica. Root collar diameter, seedling height, leaf dry weight, stem dry weight, root dry weight, and total biomass were the highest in Tm treatment. Butthey were not significantly different in the Th treatment. In the Th treatment, Q. serrata had significantly higher H/D ratio, S/R ratio, and low root mass ratio (RMR) compared with control plot. Q. mongolica had lower RMR and higher S/R ratio in the Tm and Th treatments compared with control plot. Therefore, growth of Q. mongolica are expected to be more vulnerable to warming than that of Q. serrata. The main findings of this study, species-specific responses to experimental warming, could be applied to predict ecosystem changes from global warming. From the result of this study, we could deduce that temperature rise would increase germination of Q. serrata and Q. mongolica and consequently contribute to increase establishment rate in the early growth stage of the plants. But we have to consider diverse variables to understand properly the effects that global warming influences germination in natural condition. Treatment of global warming in the medium level increased the growth and the biomass of both Q. serrata and Q. mongolica. But the result of treatment in the high level showed different aspects. In particular, Q. mongolica, which grows in cooler zones of higher elevation on mountains or northward in latitude, responded more sensitively. Synthesized the results mentioned above, continuous global warming would function in stable establishment of both plants unfavorably. Compared the responses of both sample plants on temperature rise, Q. serrata increased germination rate more than Q. mongolica and Q. mongolica responded more sensitively than Q. serrata in biomass allocation with the increase of temperature. It was estimated that these results would due to a difference of microclimate originated from the spatial distribution of both plants.

• Plant Resources
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• v.3 no.1
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• pp.71-78
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• 2000

Autotoxicity restricts reseeding of new alfalfa(Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments, often requiring up to a year or more. One solution for reducing autotoxicity would be to select germplasms or cultivars with tolerance to the autotoxic chemical(5) and use genetically breeding program. Bioassay of seed germination and early seedling growth was conducted to evaluate autotoxic responses of 3 varieties of alfalfa to the water-soluble extracts(at 4 and 8g/L) from alfalfa ‘Cody’leaf by using agar and filter paper medium in a petri-dish assay. Root length at 5 days after seeding was more sensitive to the extract than was hypocotyl length or seed germination, and was a better parameter of autotoxic effects of alfalfa leaf extracts. Use of an agar medium gave better sensitivity of root length than did use of filter paper. Evaluating tolerance with percent of control was more important indicator than was mean of root length because of significant variation among varieties in root length of control treatment. Bioassay ranked varieties in the following order of tolerance on the basis of relative root length; “Cody” >“ Pioneer 5373” >“ Alfagraze”. Seedling growth from old “Cody” seed was more sensitive to the autotoxic chemical(5) than was that from newly produced seed.