• Korean Journal of Plant Resources
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• v.5 no.1
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• pp.1-10
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• 1992

Germination characteristic between Korean species and Japanese one were identified. Seed waslow temperture germinability. Optimum temperature of germination:on was 16$^{\circ}C$ -19$^{\circ}C$. Germinationrate was effected more when treated with GA3 of 1000ppm at shade and light place. Germinationrate was no significant difference between Korean species and japanese one. e.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.174-178
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• 1986

This experiment was carried out to study the influence of temperature treatments on germination of sorghum (cv. Pioneer 931), sorghum-sudangrass (cv. Pioneer 988), sudangrass (cv. Piper) and corn (cv. Suweon 19) in growth chamber. Each crop seeds were germinated under different day/night temperature of 10/5, 15/10, 20/15, 25/20, 30/25, 35/30 and $40/35^{\circ}C$ over 14/10 hour days. The results obtained are summarized as follows. 1. Germination of sorghum and sorghum-sudangrass were less affected by high temperature than those of corn and sudangrass. The optimum temperatures for germination were $20-40^{\circ}C$ for sorghum and $20-30^{\circ}C$ for corn. High temperature($40/35^{\circ}C$), however, resulted in great decrease of seed germination rates of seed germination rates of corn, while those of sorghum and sorghum-sudangrass shown high germination rates with the value of 95.8% and 89.9%, respectively. 2. Sorghum-sudangrass hybrid was shown to have a great tolerance to low temperature. Under low temperature($10/5^{\circ}C$) seed germination of sorghum-sudangrass was 80.0% but those of corn and sudangrass were 43.2% and 24.8% respectively. Germination rates of sorghum were decreased to about 68.8% at low temperature from a value of 98.1% at optimum temperature. 3. The days required to the seed germination of sorghum and sorghum-sudangrass hybrid were shortened by increasing of temperature. Under different temperature treatments, it was required 12 days ($15/10^{\circ}C$), 6 days ($25/20^{\circ}C$) and 3 days ($40/35^{\circ}C$) in sorghum but corn required 16, 7 and 3 days, respectively.

• Korean Journal of Plant Resources
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• v.22 no.6
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• pp.535-539
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• 2009

The time of seed collection is regarded as one of major concerns to obtain sound seeds. The physical and germinal aspects of Cryptomeria japonica D. Don (Taxodiaceae) seeds were analyzed to determine the optimum harvesting time in Korea. Cones were picked every 10 days from the $30^{th}$ of July to the $30^{th}$ of October in both 2005 and 2006. Seeds were collected from picked cones. Seed size and weight were not significant in two consecutive years. The 1,000-seed weight was 3.3 g for cones picked at the $18^{th}$ of August and 5.3 g for cones picked at the $30^{th}$ of September. The size of seeds was increased as the time of collection from the $18^{th}$ of August to the $30^{th}$ of September: from 19.3 mm to 21.3 mm in length and from 15.8 mm to 18.5 mm in width. Average germination rates in 2005 was 18.3% and 19.6% in 2006. The highest germination rate was 34.3% from seeds collected at the $30^{th}$ of September in 2005. In 2006, the highest germination rate was 31.7% for seeds collected at the same date as the 2005 seeds. After the end of September, germination rate was decreased in both years. The results implied that the best cone picking time for Korean C. japonica seeds is around the end of September.

• Journal of Environmental Science International
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• v.32 no.2
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• pp.121-130
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• 2023

This study was conducted to investigate changes in seed vigor based on temperature of dry heat and duration treatment of watermelon seeds and examine the effect on percent of emergence and seedling vigor. When the upper limit temperature of dry heat treatment was raised to 80℃, the percent of the germination decreased. Moreover, T₅₀ was delayed as the upper limit temperature of dry heat treatment increased. The higher the upper limit temperature of dry heat treatment and the longer the treatment period, the higher the percentage of abnormal seedlings. The optimum upper limit temperature for dry heat treatment was 72℃, and the treatment period was five days. Seed vigor was better maintained at 30℃, 45℃, and 52℃, followed by stepwise exposure to high temperatures of 72℃, the upper limit of dry heat treatment, rather than dry heat treatment at a high temperature of 72℃ for 5 days from the initial stage of treatment. When the fungicide was added during the dry heat treatment process, the germination percentage decreased and the percent of the abnormal seedling percentage increased. However, the addition of 10 mg/kg fungicide did not significantly reduce seed vigor.

• Journal of Environmental Science International
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• v.23 no.5
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• pp.771-780
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• 2014

Tetragonia tetragonides is a medicinal plant native to ocean sand soil of southern provinces and has significant effects on the prevention and curing of gastroenteric disorders. Despite of its popularity, supply of the plant has never met the level of demand because of the absence of an adequate culturing method. The present study, thereby, was conducted for classifying the plants with geographically different characteristics, studying growth habits, developing a new culturing method and establishing a large scale propagation system of selected superior individual plants. The study was also aimed for revealing optimum conditions for seed treatment, fertilization, and efficient culturing system and thereby, for utilizing the plant as a new income source for rural communities. The seed was elongated with size of 2.6 mm (width) ${\times}$ 1.8 mm (length). No difference in seed size was observed depending on different inhabitate. Each flower produced about 4.5~4.8 seeds. Germination rate was high for seeds matured for 40 days after fertilization, but deceased to 50% for seeds matured only for 20 or 30 days. Seed dormancy lasted 6 months and seed storage at humid $5^{\circ}C$ facilitated germination. Mechanical obstruct of seed germination was due to seed coat and removal of seed coat enhanced the germination rate. Optimum temp. for seed storage was $5^{\circ}C$, and high germination rate was maintained for 350 days. However, for stratification condition or at room temperature, germination was significantly reduced as storage time increased Optimum treatment of plant growth regulators was soaking in $GA_3$ 250 mg/L for 1 hr. The priming treatment with 50 mM $Ca(NO_3)_2$ at $20^{\circ}C$ for two days improved the seed germination with 10% compared to non-treated control. The treatment of 20% NaOCl for 3 hr. improved the seed germination rate up to 10% and 1 day ahead.

• Korean Journal of Medicinal Crop Science
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• v.8 no.2
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• pp.129-133
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• 2000

The experiment was conducted to increase germination of Agrimonia pilosa seeds, one of the natural medicinal plants, by various treatments, and also the effects of seed treatments on the growth of plants after sowing in field. The optimum temperature for germination of A. pilosa seeds was $20^{\circ}C$ after 20 days stratification duration at $4^{\circ}$, the germination rate than highest, 86% at that temperature. The stratification increased germination rate in all the temperatures treated, shortened $26{\sim}32$ days of germination period and promoted more 20% germination rate than the other treatments. Flowing water, low temperature, $GA_3$ and NaOCl were not effective for germination and high temperature reduced germination rate. At the early growth stage, the plant height was taller $3{\sim}4\;cm$, one or more leaves were increased by the stratification treatments, and also stratification increased the number of leaves per plants 10 or more leaves compare with other treatments at harvesting stages. By stratification, the flowering date was 5 days earlier, June 18th than other treatments due to earlier sprouting.

• Korean Journal of Plant Resources
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• v.36 no.4
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• pp.381-389
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• 2023

The germination characteristics of Pseudolysimachion kiusianum var. diamantiacum (Nakai) T.Yamaz., a rare and endemic plant designated by the Korea Forest Service, were investigated according to light conditions, temperature, and pretreatment. As a result of the germination experiment according to light conditions, it was determined that P. kiusianum is a photoblastic seed that does not germinate at all in dark conditions. The optimum germination temperature of the seeds was found to be 20-25℃, considering the final germination rate and germination time. Three growth regulators (IAA, GA₃, kinetin) and two inorganic salts (KNO₃, KCl) were pretreated to improve the germination rate of P. kiusianum seeds. The growth regulators IAA and kinetin had no significant effect on improving the germination rate of P. kiusianum seeds. On the other hand, GA₃ significantly increased the final germination percentage and germination rate regardless of the concentration, especially the treatment of more than 500 mg·L^-1 at 20℃ was more than 4 times more effective than the untreated. The inorganic salts KNO₃ and KCl had no significant effect on the seeds of P. kiusianum at low concentrations, but at higher concentrations (40 mM and 300 mM, respectively), they improved the germination rate and germination age by 2 times compared to the untreated. The results of this study will be useful for the mass propagation of P. kiusianum, which has the potential to be utilized as a native plant for restoration.

• Korean Journal of Plant Resources
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• v.20 no.5
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• pp.398-403
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• 2007

This study was carried out to enhance germination of the seed by different immersion temperatures(15, 20, 25, 30 and $35^{\circ}C$) and times(1, 6, 12, 18, 24, 36 and 48 hours) in Cryptomeria japonica that is a major plantation species in the southern Korea. Optimum germination temperature was between $20^{\circ}C$ and $25^{\circ}C$, and the lowest germination was observed at $35^{\circ}C$ Moisture absorption increased with increasing immersion time as a whole and was high at $30^{\circ}C$ and $35^{\circ}C$. Initial moisture absorption rate was highest at $30^{\circ}C$ whereas was lowest at $15^{\circ}C$ Moisture absorption rate constant was also high at $30^{\circ}C$ and $35^{\circ}C$, however, it was relatively low at $15^{\circ}C$ and $20^{\circ}C$ Germination was the highest when the seeds were immersed for 48 hours at $30^{\circ}C$. In mean germination time(MGT) the seeds immersed for 48 hours at $30^{\circ}C$ did not differ from non-treatment, while the others showed higher values than non-treatment. Consequently, germination could be enhanced and MGT was kept by optimum immersion temperature and time.

• Asian Journal of Turfgrass Science
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• v.24 no.1
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• pp.31-35
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• 2010

Several experiments were conducted to investigate the germination characteristics among the Rumex crispus, R. japonicus, R. obtusifolius, and R. nipponicus. The germination point of R. japonicus was started 4 days after application, and then R. obtusifolius (5th), R. crispus (6th), R. nipponicus (10th) with appeared order. The optimum temperatures for germination of all tested Rumex spp. occurred at the $15^{\circ}C$. Especially, R. obtusifolius will have the widest germination range at $10^{\circ}C{\sim}30^{\circ}C$. To compared with 1996 and 2004 year selected R. japonicus germination were did not significantly difference, otherwise, all tested Rumex spp. on dark condition was not germinated. The parameters of germination characteristics of Rumex spp. were investigated mean germination rate (MGR, %), mean germination time (MGT, day), mean germination velocity (MGV, No./day), and coefficient of germination uniformity (CGU). The R. japonicus compared in tested Rumex spp. showed the highest MGR. The MGT and MGV of R. obtusifolius was appeared the earliest compared with R. obtusifolius and R. crispus.

• Asian Journal of Turfgrass Science
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• v.8 no.1
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• pp.1-11
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• 1994

Studies were conducted to evaluate the effect of priming and preimbibition on gerraination of unscarified and KOH-scarified zoysiagrass (Zoysia japonica Steud.) seeds, respectively. Germi-nation percentages at 35˚C of seeds primed in $KNO_3$ and Ca($NO_3$)$_2$ were significantly higher than that of untreated seeds. The optimum conditions for priming unscarified seeds were in aerated $KNO_3$ solution at O4 M for 4 days at 20˚C. No additional benefit of $GA_3$ on increasing germination was not found in seed priming with solution of $KNO_3$ + $GA_3$ or in seeds preimbibed with $GA_3$ after priming. Scarified seeds preimbibed with distilled water(DW) for 4 days at 20˚C germinated higher and with fewer days to 50% of total germination(T 50) than untreated seeds. Preimbibition with $GA_3$ solution at 50 ppm for 4 days at 5, 10, 15 and 20˚C enabled up to 97% of seeds to germinate and reduced days to T 50 about 1.1 to 1.2 days at 35˚C Especially, seeds preimbibed with $GA^2$˚$_3_2_1$$\times$ had greatly higher germination and lower T 50 than untreated or DW-preimbibibed seeds at 30˚C, which is inadequate to germination in general. Preimbibed seed performance was unchanged after storage at room temperature for 50 days. Seeds preimbibed with GA $_3$ had higher rate of seedling emergence and faster growth of shoot than untreated seeds after sowing at 30˚C in growing medium in growth chamber.