• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.39-42
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• 2014

The objective of this study was to estimate cardinal temperatures for germination of lettuce (Lactuca sativar L.) using bilinear, parabolic, and beta distribution functions. Seeds of lettuce were germinated in a growth chamber at 7 constant temperatures: 10, 14, 16, 20, 24, 28, and $32^{\circ}C$. Four replicates of 100 seeds were placed on two layers of filter paper in a 9 cm petri-dish. Radicle emergence of 1 mm was scored as germination. The time course of germination was modeled using a logistic function. These minimum, optimum, and maximum temperatures were estimated by regression of the inverse of time to 50% germination rate against the temperature gradient. In bilinear function, minimum, optimum, and maximum temperatures were $7.9^{\circ}C$, $23.3^{\circ}C$, and $28.0^{\circ}C$, respectively. In parabolic function, minimum, optimum, and maximum temperatures were $9.7^{\circ}C$, $19.5^{\circ}C$, and $29.4^{\circ}C$, respectively. In beta distribution function, minimum, optimum, and maximum temperatures were $3.7^{\circ}C$, $20.7^{\circ}C$ and $32.0^{\circ}C$, respectively. Minimum, optimum, and maximum ranges of temperatures were $3.7{\sim}9.7^{\circ}C$, $19.5{\sim}23.3^{\circ}C$, and $28.0{\sim}32.0^{\circ}C$, respectively.

• Korean Journal of Medicinal Crop Science
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• v.4 no.2
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• pp.163-171
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• 1996

The influences of temperature, harvest time, sowing time, seeding media, moisture content of media and light on the seed germination of Lycoris are as follows, Both L. koreana and L. aurea had over 90% seed setting, and seed maturity came in September or early October. It took six months to have over 60% seed germination. The optimum germination temperature was $25^{\circ}C$, and the alternating treatment was effective at $20{\rightleftarrows}25^{\circ}C$. The optimum harvest-time was around Sep. 20, and the optimum seed-time was immediately after havest. The optimum seeding media was sand loam, and the optimum moisture content was PF 1. 9/400ml seeding media. The dark condition was more effective for the seed germination than the light condition.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.265-272
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• 1988

This experiment was carried to investigate the germination pattern in relation to temperatures and lights, and the emergence pattern in relation to seeding depths, lights and the alpha amylase activity of Youngia sonchifolia, Lactuca indica var. laciniata, Ixeris dentata var. albiflora and Ixeris polycephala. In Y. sonchifolia, the optimum germination temperature was $25^{\circ}C$, the optimum seeding depth to emerge was 0 mm and it could emerge in 0-5mm. In L. indica var. laciniata under cool storage, the optimum germination temperatures were $19^{\circ}C-28^{\circ}C$, the optimum seeding depth was 5mm and it could emerge in 0-20mm. In L. indica var. laciniata under room storage, the optimum germination temperature was $25^{\circ}C$ the optimum seeding depth was 5mm and it could emerge in 0-10mm. In I. dentata emerge was and 0mm and it could emerge in 0-5mm. In I. polycephla, the optimum temperatures were $16^{\circ}C-19^{\circ}C$, the optimum seeding depth to emerge was 0mm and it could emerge in 0-5mm. The alpha amylase activity was lower Y. sonchifolia, L. indica var. laciniata and I. dentata var. abiflora than barley cultivar Dongbor#1. And the increased pattern of alpha amylase activity was likely to it of germination rate.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.9-14
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• 2010

Several presowing seed treatments have been used to facilitate the seed germination and seedling emergence. The study was performed to design a model of presowing seed treatments in Taraxacum platycarpum. Germination and seedling growth responses to temperature, drying, chilling, $GA_3$ and priming were investigated to know the optimum germination conditions and presowing treatment. The optimum temperature condition for germination and seedling growth were $15{\sim}20^{\circ}C$ at dark condition. The seeds exposed to infra red light, however, did not germinate. The moisture content of seeds dried at $35^{\circ}C$ for 3.5 hours was returned to the level of unimbibed seeds. The germination of seeds dried under dark condition was better than those dried under infra red light. Prechilling treatment imposed for 6 weeks showed higher germination rate than $GA_3$ treatment or priming. In field test, the highest field emergence was observed in the seeds dried after prechilled for 6 weeks and followed by drying followed by $GA_3$ > low temperature > $KNO_3$ priming. Imbibition with 0.1 mM $GA_3$ solution for 2 hours then drying at 35 for 3.5 hour under dark condition was effective to the practical presowing treatment for Taraxacum seeds.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.166-172
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• 2001

This study was conducted to investigate the optimum condition of breaking dormancy and to increase the germination rate of Hovenia dulcis Thunb. seeds. Germination of seeds which did not germinate at the various constant temperature was induced by the artificial breaking of seed coat, and the germination rate of seeds which the seed coats were broken was the highest(94%) at $15^{\circ}C$. The germination rate of seed was highest when seeds were treated with concentrated $H_2SO_4$ for 40 minutes. When seeds were stored in dry condition, the germination capability was maintained up to 5 years after harvest. However, their germination rate become lowered and average germinating duration was extended. Germination rate of seeds which were stored for 5 years significantly increased by the low temperature treatment more than 30 days.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.359-364
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• 2014

This text was experimented and investigated the optimum production time and germination characteristic of Fabaceae plant seed that collect in Korean Chungnam. Optimum time of seed production was early-mid October of Chamaecrista nomame, early November of Lespedeza cuneata and early-mid November of Lespedeza bicolor. Epiphytic amount of seed full ripe was the most times in early October of Chamaecrista nomame, early November of Lespedeza cuneata and Lespedeza bicolor, respectively. Seed rate of maturity was the highest times in early November of Chamaecrista nomame, mid November of Lespedeza cuneata and Lespedeza bicolor, respectively. Germination rate by seed collection time was the highest times in early October of Chamaecrista nomame (99.8%), mid November of Lespedeza cuneata (68.3%) and early November of Lespedeza bicolor (24.3%). Germination days by seed production time was the shortest times in mid October of Chamaecrista nomame, mid November of Lespedeza cuneata and Lespedeza bicolor, respectively. Optimum temperature of germination was $15{\sim}35^{\circ}C$ in Chamaecrista nomame, $25{\sim}30^{\circ}C$ in Lespedeza cuneata, and Lespedeza bicolor was difficult judgment of germination optimum temperature because of low germinating rate.

• Korean Journal of Plant Resources
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• v.22 no.3
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• pp.236-241
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• 2009

Dracocephalum argunense Fischer ex Link (Labiatae) is a perennial herbaceous plant used as valuable materials for ornamentals, honey production, and pharmaceutics. Since seed germination of this species was quite difficult, present studies were conducted to improve the germination rate by subjecting the seeds to various environmental conditions (temperature and light) and treatments (scarification, priming and seed coating). Optimum temperature for adequate germination was 20$^{\circ}C$ though it ranged from 15$^{\circ}C$ to 25$^{\circ}C$, and low temperature treatment improved germination rate. Light was required for higher germination rate in this species. The scarification of seeds resulted in much higher germination, especially by the physical treatment with sandpaper or chemical treatment with sulfuric acid for 30 seconds. Various primers with different concentrations were treated on the seeds and it was demonstrated that low temperature enhanced germination rate, regardless of kinds and concentrations of the primers. Three treatment combinations of the primers, 0.5 mM $GA_{3}$ treated for 48 hours, 0.5 mM IAA for 24 hours, and 1.0 mM IAA for 24 hours, increased the seed germination rate profoundly. Soaking treatment of inorganic salts, $KNO_{3}$ and $KH_{3}PO_{4}$, promoted germination when seeds were subjected to low temperature. Water soluble primers such as sucrose at 0.5 and 3% concentration and solid primer talc powder were effective in enhancing germination rate.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.2
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• pp.71-81
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• 2016

This text was experimented and investigated the optimum production time and germination characteristics of seed that collect in Korean Chungnam, in order to offer the basic informations for slope restoration and revegetation using Poaceae plant. Optimum time of seed production was mid-late October of Miscanthus sinensis, Pennisetum alopecuroides, early November to late October of Themeda triandra var. japonica and M. sacchariflorus, and mid November of Phragmites communis. Epiphytic amount of seed full ripe was the most times in mid October of M. sinensis, P. alopecuroides and M. sacchariflorus, early November of T. triandra var. japonica, and mid November of P. communis. Seed rate of maturity was the highest times in early November of M. sinensis, P. alopecuroides and M. sacchariflorus, and mid November of T. triandra var. japonica and P. communis. Germination rate by seed collection time was the highest times in early October of M. sacchariflorus, mid October of T. triandra var. japonica, early November of M. sinensis and mid November of P. communis. Germination days by seed production time was the shortest times in early November of M. sinensis and M. sacchariflorus, mid November of T. triandra var. japonica and P. communis. Optimum temperature of germination was $20{\sim}25^{\circ}C$ in M. sinensis and P. alopecuroides, $25^{\circ}C$ in T. triandra var. japonica, and $25{\sim}30^{\circ}C$ in P. communis.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.2
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• pp.201-206
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• 1985

This experiment was carried out to get the basic information about long term storage (Temp.: -10${\pm}$1$^{\circ}C$ and -l${\pm}$1$^{\circ}C$, RH; 30${\pm}$6) of rice germplasm by using three Japonica and one Indica x Japonica cultivars based on the storage periods (96, 86, 58 and 20 months). The germination ability, based on the storing periods, was tested under the conditions of 30-32$^{\circ}C$ and 15-17$^{\circ}C$ air temperature. The results obtained are summarized as follows: 1. There were no significant differences between the short and long term storage conditions in the percentage of germination, average germination period, germination coefficient of the four varieties tested under both 15-17$^{\circ}C$ of low and 30-32$^{\circ}C$ of optimum temperature conditions. 2. Eventhough there were no significant differences in germination depending on the storage periods under optimum temperature condition (30-32$^{\circ}C$). Longer storage duration resulted in lower germination percentage, longer average germination period and lower germination coefficient under low temperature condition (15-17$^{\circ}C$). Comparing the varieties, the germination percentage of a Indica/Japonica cultivar "Tongil" was lower than that of Japonica cultivars under the low temperature condition (15-17$^{\circ}C$). 3. The longer period of storage, the more abnormal plants had appeared. 4. The germination ability was lost earlier under the condition of high moisture content in the seed and non-ventilation container.

• Korean Journal of Environmental Biology
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• v.30 no.3
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• pp.280-285
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• 2012

We investigated germination rate of Zostera marina and Phyllospadix japonicus, which are the most two abundant seagrass species of Korea, in related to light, salinity and temperature. Light had no significant effect on Z. marina germination, but it promoted P. japonicus germination. The highest germination of Z. marina appeared in 0 psu, and that of P. japonicus appeared in 15 psu. The optimum water temperatures for germination of Z. marina and P. japonicus were $5^{\circ}C$ and $15^{\circ}C$, respectively. These differences of optimum germination requirements of Z. marina and P. japonicus were probably caused by the difference of the habitat environment of the two seagrass species. Since few data exist concerning germination of Korean seagrasses, this study provides valuable information for the conservation of seagrass habitats in Korea.