• Journal of Plant Biotechnology
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• v.40 no.1
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• pp.43-48
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• 2013

Oreorchis coreana Finet is threatened globally by over-collection from its natural habitats for horticultural purposes. Its rarity in nature makes this plant one of the most endangered species in Korea. In this study, we investigated the effects of sodium hypochlorite (NaOCl) on orchid seed viability and seed germination. An in vitro bioassay swelling test using immature seeds was compared with a standard chemical procedure using triphenyl tetrazolium chloride (TTC) to test seed viability. In general, the bioassay was more appropriate for estimating embryo viability after a prolonged pre-treatment (more than 1 h) in 1% NaOCl, a surface sterilant often used to enhance germination of seeds of terrestrial plants. Therefore, an efficient method for investigating in vitro swelling of immature seeds is urgently needed. We established a method for determining the viability and swelling of O. coreana seeds via in vitro examination of immature seeds. Treatment of immature seeds with 1% NaOCl for 10 min greatly enhanced the extent of swelling of immature zygote embryos when compared to untreated seeds. These data obtained here appear to be comparable to viability and swelling that occurs in O. coreana seeds via asymbiotic germination.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.137-141
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• 2006

Germination characteristics and alterations in soluble sugar-starch transition and phytic acid during germination were studied in rice seeds under saline conditions. NaCl significantly reduced the speed of germination. Also, the radicle growth out of seeds was severely inhibited by the exposure to NaCl solution, thus, seeds were almost impossible to grow to seedlings. Soluble sugar was remarkably accumulated, whereas starch was decomposed stepwise during seed germination. The metabolism of soluble sugar and starch in germinating seeds showed a distinct difference. The level of phytic acid in seeds decreased in all NaCl treatments during germination, but the level was affected differently by NaCl concentration in the two varieties. Overall, our results suggest that salt stress retard the radicle growth of rice seeds, and affect the starch-to-sugar conversion and the decomposition of phytic acid differently in two varieties.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.2
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• pp.258-261
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• 1983

This experiment was conducted to evaluate the effect of early seed harvest on germination of tobacco(Nicotiana tabacum L.) seeds. Seeds of seven burley tobacco were harvested every two days from 8 to 30 days after pollination and tested for germination. The results are; 1. Seeds harvested 12days after pollination germinated but germination rates were low and varied across cultivars. These seeds will provide viable seeds adequate for breeding program. 2. Germination rates of seeds harvested 24-28 days after pollination were high and showed none significant differences among cultivars. 4. Over-ripen seeds showed low germination rates cused by after-harvest or temporary dormancy.

• Korean Journal of Medicinal Crop Science
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• v.24 no.1
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• pp.21-26
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• 2016

Background : Acer pictum is a deciduous tree belonging to the family Aceraceae. This study was conducted to collect basic data on mass propagation techniques by surveying the germination and growth characteristics of A. pictum seeds. Methods and Results : A. pictum seeds were harvested in 2014 on August 19, September 5, September 29 and October 31. The seeds were then sown on the same dates they were harvested. A portion of seeds harvested in August 2014 were stored at low temperatures and subsequently sown on March 11, 2015. The germination rate of A. pictum seeds was highest in seeds that were stored harvested on October 31. Mean germination time (MGT) was shortest and germination velocity (Rs) was fastest in seeds harvested on October 31. Root collar diameter, total root length, and dry weight were also highest from seeds collected October 31. Conclusions : A. pictum seeds harvested on October 31 had highest germination and growth rates compared with seeds harvested on earlier dates. It is expected that these results demonstrating optimum harvesting and sowing dates will be applicable to future seedling production for this tree species.

• Horticultural Science & Technology
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• v.34 no.4
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• pp.557-563
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• 2016

To improve the germination of Spiraea fritschiana seeds for mass propagation, we evaluated the effect of a range of temperatures, cold stratification periods, and gibberellic acid ($GA_3$) treatments on three germination characteristics. Final germination percentage (FGP) increased as the temperature for seed germination increased, up to $30^{\circ}C$, while the mean germination time (MGT) and the mean number of days to 30% germination ($T_{30}$) decreased when seeds were germinated at $25-30^{\circ}C$. The optimum germination temperature of S. fritschiana seeds is approximately $30^{\circ}C$ considering FGP, MGT, and $T_{30}$ together. FGP increased with the duration of cold stratification up to a period of 6 weeks, but declined after 8 weeks of cold stratification, as prolonged cold stratification can induce dormancy with a resultant decline in germination. Pretreatment with 6-8 weeks of cold stratification or soaking seeds in distilled water or $500mg{\cdot}L^{-1}$ $GA_3$ for 24 h accelerated and increased the germination of S. fritschiana seeds, regardless of temperature. However, further study might be required to evaluate the effect of $GA_3$ concentrations lower than $500mg{\cdot}L^{-1}$ on the promotion of germination in S. fritschiana seeds.

• Journal of Environmental Science International
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• v.25 no.4
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• pp.557-566
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• 2016

In nine commercial watermelon cultivars, the effects of osmotic seed priming were evaluated for seed viability and seedling growth at different germination temperatures and field conditions. Generally, primed seeds showed improved germination rate and reduced time for emergence at different germination temperatures, as compared to untreated seeds. In particular, priming effect on seed germination was significantly high at $15^{\circ}C$, which is an environment normally resulting in poor germination. Depending on the watermelon cultivar, germination rate under low temperature ($15^{\circ}C$) was improved by up to 15~66% in primed seeds, as compared to untreated seeds. However, priming effect on germination was gradually reduced as the temperature reached to its optimum level for seed germination. Seed priming tended to improve the viability, fresh weight, and dry weight of watermelon seedlings, but its effect on seedling stage was not large, as compared to untreated seeds. Primed watermelon seeds showed improved emergence rate and facilitated germination in the field, but their seedling growth after 30 days from germination was not significantly affected. Our results indicated that seed priming can greatly improve the seed germination at poor temperature conditions in the watermelon.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.1
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• pp.19-24
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• 2004

Germination and emergence habits of Chinese milk vetch (CMV) were examined to obtain the basic information for the effect of environmental conditions and cultural practices on the seedling density. Seed germination tests with different water potentials, temperatures, and soil and water depths showed the environmental effects on the characters related to seed germination in CMV. Imbibition under different temperatures reflects that initial velocity was rapid at higher temperature, however, the times to full imbibition were not different between 15 and $25^{\circ}$. The optimal germination temperature for CMV germination was ranged from 15 to 20 and the germination was highly affected by water potential of media at relatively high temperature above $20^{\circ}$. When the seeds were sown in flooded condition the germination was not proportionally affected by water depth. In addition, there was no correlation between water depth and oxygen concentration. The germination of seeds flooded by 2cm water depth were poorly germinated compared to other depths. Results indicated that the germination of submerged seeds was more highly influenced by flooding depth than the temperature, it was also affected more strongly at 10 than $20^{\circ}$. Emergence of CMV depending on the thickness of covered soil was poor when the soil layer was greater than 5cm. In the experiment with seeds collected between 22 days after flowering (OAF) and 52 DAF, the highest germination ability of CMV seeds was observed at 39 DAF and germinability was decreased subsequently as seeds became mature. The lower germinability may be due to the enhanced seed dormancy.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.9-15
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• 2017

Germination characteristics, seedling emergence, and early seedling growth of iron-coated rice seeds, cultivars Daebo and Samdeokbyeo, under different water depths were compared with those of non-coated seeds (control) and the results evaluated to obtain basic information for establishing stable seedlings in direct water seeding. The total germination percentage of the two seed treatments was similar, but iron-coated seeds had slightly faster germination and shorter mean germination time than non-coated seeds. Water absorption rates of iron-coated seeds were lower than that of non-coated seeds during seed germination. The germination percentage of the two iron-coated rice seed cultivars showed a significant decline of 15-22% after one year of storage under natural conditions. The seedling emergence percentage and uniformity of the two rice cultivars were significantly higher in the iron-coated seeds at 1-13 cm water depths but the percentage of floating seedlings was lower in iron-coated seeds than in non-coated seeds. The iron-coated seeds had a high seedling emergence percentage of 91.3-93.3% at all flooding depths whereas the non-coated seeds had a significantly low seedling emergence percentage of 57.7-71.7% at a water depth of 13 cm. Moreover, the shoot dry weight and seedling health score of iron-coated seeds were significantly higher than those of non-coated seeds, while root dry weights were similar in iron-coated and non-coated seeds, regardless of water depth. These results suggest that iron-coated seeds are more appropriate for stable seedling establishment in direct water seeding than are non-coated seeds.

• Asian Journal of Turfgrass Science
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• v.3 no.2
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• pp.65-72
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• 1989

Tes ratablish a liawn Zoysia' Japonica Steud. with seeds. a experiment was conducted for the invrati ignt ic in oil seed's physic sit ogical maturity. The rt.sultt an' Summarized as follows: 1. The point of maximum weight off 1000 seeds and 100 seedling, germination speed and germination percentage were reached at 30 day. after anthesis. it would be considered as physiological maturity of Zoysia japonica seed. 2. The seeds moistures contents at physiological maturity was decreased in 18%. 3. Germination vigor deteriorated prior to viability. 4. The seeds were capable of germination in 3:4% at 10 days after anthesis. 5. Field deterioration of seeds occurer from 40 (lays after anthesis to 60 days and sprouted seedilng vigor was very poor.

• Korean Journal of Plant Resources
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• v.27 no.3
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• pp.256-262
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• 2014

Viscum album var. coloratum (mistletoe) is considered as one of the endangered plant species in Korea. Our objective is to restore its population and multiplication of plant by ex situ method. In this research we explored the maximum germination (in vitro) of freshly harvested and stored seeds of mistletoe collected in different time intervals. Ex vitro germination after artificial inoculation on the branches of Prunus mume in different physiological conditions was also monitored. The research revealed that the lately harvested seeds (Feb. and March 2014) were superior over early harvested seeds (Nov. 2013 and Jan. 2014) of mistletoe due to the higher percentage of germination (above 93%). According to the data, it is also revealed that the survival and germination rate of mistletoe seeds decreased with the increase in storage duration. In ex vitro germination, the fluctuated temperature of a glass house in natural condition enhanced (four fold) the rate of germination on the branches of Prunus mume than the constant temperature condition in the glass house.