• Korean Journal of Medicinal Crop Science
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• v.24 no.3
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• pp.177-182
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• 2016

Background: Many Taraxacum spp. plants are widely used in medicine, but some of them have propagation problems, such as strong dormancy and poor germination rates. This study investigated the effects of temperature, gibberellic acid ($GA_3$), and potassium nitrate ($KNO_3$) on seed germination in Taraxacum ohwianum. Methods and Results: The seeds (NIBRGR0000135524) were exalbuminous, and their length and width were $4.54{\pm}0.032mm$ and $0.97{\pm}0.029mm$, respectively. Various germination temperatures were tested (15, 20, 25, and $30^{\circ}C$), the optimum temperature for germination was found to be $20^{\circ}C$ (31.3%). High temperature ($30^{\circ}C$) resulted in non-typical seedlings (thickened and crumpled cotyledons, with a restricted root system). To increase the germination capacity, $GA_3$ (200, 500, and $1,000mg/{\ell}$) or $KNO_3$ (20, 50, 100, 200, and $500mg/{\ell}$) solutions were used as pre-soaking solutions instead of water. The $GA_3$ treatments increased the germination percentage and rate, but germination percentage was higher with the $KNO_3$ treatments. Under the $50-200mg/{\ell}\;KNO_3$ treatments, the germination percentage exceeded 80% after 12 days, and $50mg/{\ell}\;KNO_3$ was notably effective (91.2% after 15 days). Conclusions: T. ohwianum seeds showed improved germination at low temperatures. The best method for germination was presoaking in $50mg/{\ell}\;KNO_3$ for 24 h, in the dark at $4^{\circ}C$, and then incubating the germinated seed at $20^{\circ}C$ for 15 days.

• Korean Journal of Medicinal Crop Science
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• v.21 no.6
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• pp.461-465
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• 2013

This study was investigated to evaluate germination rate of Astragalus membranaceus B. in Korea as affected by storage temperature, germination temperature and storage period of seed. The highest germination rate was obtained from condition of $25^{\circ}C$ in germination temperature. Seeds were stored at $-20^{\circ}C$ and $5^{\circ}C$ for 8 weeks has showed higher germination rate than one at room temperatures. The germination rates showed significantly difference by harvested year of 2010, 2011 and 2012. The seed of A. membranaceus in harvested year of 2011 and 2012 had germinated well. On the other hand, seeds in harvested year of 2010 were not nearly germinated. Consequently, the longer storage period after seed harvest lower germination rate and seed vigor as well.

• Korean Journal of Environment and Ecology
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• v.12 no.1
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• pp.9-13
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• 1998

Because Lysimachia mauritiana is not able to maintain the seed viablity for a long time, it has difficulties in using for the ornamental plants or landscape gardening. This study was conducted to elucidate the optimal germination conditions of Lysimachia mauritiana seeds. The germination rate of the seeds was higer in light condition than in dark one. In experment determining the proper germination temperature, the germination rates were 2.2%, 96.9% and 91.2% under 35$\circ $C, 25$\circ $C, and 20$\circ $C, respectively in light condition. The approprate temperature for the germination was 25$\circ $C in light. The decreases of germination rate with the increase of the preservation periods was able to recover by priming pretreated with NaCl solution and KNO$_{3}$ + K$_{3}$H$_{2}$PO mixed solutions. When the storage period was 300 days, the germination rate was 75% without priming treatments. But the seeds primed with NaCl 0.1M and KNO$_{3}$ + K$_{3}$H$_{2}$PO mixed solutions 0.1M, showed germination rate above 90%. T$_{50}$ also was shorten from 5.25 without priming to 3.78 with NaCl 0.1M. Seed priming may induce earlier sprouts and increase germination rate of long-preserved seeds of native wild plants.

• Horticultural Science & Technology
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• v.34 no.3
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• pp.372-382
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• 2016

In this study, we investigated the effect of seed collection stage and alternating temperature on the germination of Deutzia paniculata (Hydrangeaceae). The seeds were collected from naturally growing D. paniculata populations in Mt. Palgong, Gyeonsangbuk-do, Korea every two weeks over a three month period from August through October, 2014, totaling five collections. We examined seed characteristics such as seed size (length and width) and weight, and germination percentages for each collection stage under four different germination temperature regimes. We also examined germination after 30 and 60 days of cold moist stratification. Each collection phase had a different germination percentage and the lowest germination percentage was observed in the seeds from phase I (average GP of 15.7%). The germination percentage was similar at the later collection phases and in the higher temperatures suggesting that later collection times and higher temperatures are optimal for D. paniculata germination. We found that the optimum collection stage with high viability and germination percentage of for D. paniculata was during the middle of the September.

• The Korean Journal of Ecology
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• v.19 no.4
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• pp.329-340
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• 1996

The extracts of selected plants and analyzed phenolic compounds were used to study the effects of alleloKDICicals on seed germination and seedling growth. HPLC analysis of the aqueous extracts of seven species identified 15 phenolic compounds including caffeic acid. Among them, protocatechuic acid was detected at 65.87ppm and 6.84ppm, in Erigeron canadensis and Pinus rigida, respectively. And the extract of P. rigida showed the strongest inhibitory effect on seed germination. The extract of P. rigida leaves significantly inhibited germination and radicle growth of Raphanus sativus var. hortensis for. acanthiformis in direct proportion to concentration. However, germination of Cassia mimosoides var. nomame was stimulated by the treated extracts at the same concentrations, but root growth was inhibited at high concentrations. Except chlorogenic acid, eleven of the twelve phenolic compounds inhibited the germination of R. sativus var. hortensis for. acanthiformis. In the case of C. mimosoides var. nomame, some phenolic compounds such as chlorogenic acid, vanillic acid, protocatechuic acid, ferulic acid, gallic acid and ${\rho}-coumaric$ acid stimulated germination, while the others reduced it.

• The Korean Journal of Ecology
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• v.9 no.1
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• pp.19-24
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• 1986

Effects of temperature, pH, light-and-dark and degree of oxygen supply on germination of Papaver somniferum L. seeds were investigated. The optimum temperature of the germination was 2$0^{\circ}C$, but the germination was decreased as temperatures changed to the upper and lower. The largest elongation of both radicle and hypocotyl also occurred at 2$0^{\circ}C$. The best germination occurred at pH 7 but this decreased suddenly the above and below of that pH value. Although no effect of light-and-dark on the germination was, this was restricted under limited. oxyten supply in terms of underwater germination as compared with abovewater one.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.2
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• pp.134-138
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• 2000

Most parts of alfalfa plant have been reported to contain autotoxic substances that inhibit seed germination and early seedling growth, however, the chemical(s) is not still studied much. Effect of seed leachates of 'Vernal' alfalfa (Medicago sativa L.) was evaluated for inhibition of alfalfa germination and root growth through bioassay. Alfalfa seeds were extracted in 1 L deionized water for 1 h after soaking and the leachates caused to reduce root length of alfalfa significantly as the soaking time increased. Crude seeds at 4 g L$L^{-1}$ exudated autotoxins that reduce significantly root length by 34 % compared to the control, when the seeds soaked in deionized water for 24 h. However, the extracts did not affect final germination as well as speed of germination. Extracts from ground seeds significantly reduced speed of germination (GT 50) and root length. The results indicate that release of autotoxic substances from seeds during seed imbibition was increased with increase of soaking time and seed amount, and that autotoxicity was more occurred in ground seeds than in crude seeds.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.106-110
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• 1998

The present study has been undertake to obtain the fundatmental data of optimum germination condition and to establish storage time for artificial pollinationin Codonopsis lancelata pollen. In vitro condition for germination of freshly collected and stored pollen were examined. The optium temperature for germination of fresh pollen was $25^{\circ}C$. The optium sucrose concentration in the medium ranged from 30 to 40 % and optium pH 6.0% for pollen germination. The rate of pollen germination accelerated considerably in the medium with 1% agar. 30% sucrose, and pH 6. C. lanceolata pollen remained viable for 15 days when stored at 5$^{\circ}C$ with silica gel as desiccant.

• Korean Journal of Plant Resources
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• v.7 no.2
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• pp.133-135
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• 1994

Germination rate of encapsulated somatic embryos shelved significant differences under different concentrations of AgN03. The highest germination rate of 81.2% was found on MS medium withouthormones mixed with 10 mg/1 of AgN03. In vitro vermiculite planted with encapsulated embryostreated with 10 mg/1 of AgN03 induced 24.7% germination rate, and vermiculite planted with encap-sulated embryos treated with 40 mg/1 or 80 mg/1 of AgNO, induced no germination at all.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.43-47
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• 1989

Characteristics and roles of protease released during the germination of Dictyostelium discoideum spores were investigated. When geat activated, the spores germinated, progressively releasing the protease into the extracellular medium. The protease activity exhibited high at pH 2.5. When cyclogeximide was added to culture, complete germination (emergence) and protease release were stopped. Addition of purified nonspecific protease to culture speeded up germination. These results suggest that excreted protease may play a role in removal of the spore wall.