• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.477-482
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• 1986

This trial was carried out to set up a proper drum speed of thresher to minimize the mechanical damage from threshing and thereby to obtain rye seeds possessing higher qualities for seeds. Rye plants were harvested at from 40 to 60 days after heading (DAH) with 5 days intervals and spread out on the field for 0, I, 2, 3 days for drying, respectively. After drying the plants were subjected to threshing at seven steps of drum speed from 400 to 1000 rotation per minute (RPM) of a thresher, drum diam. 18.6cm, teeth length 6cm. At 500 to 600 RPM and from the plants harvested at 55DAH with drying for one or two days, the seeds possessed low grain damage, high germinability over 90%, and field emergence rate over 80%.

• 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.31 no.2
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• pp.143-149
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• 1986

Anatomical changes in the forming and germinating processes of tobacco seeds were investigated to obtain basic information on the ecological characteristics of tobacco seeds. Seed development studied through the longitudinal section of the fertilized ovule clarified that the cell division of the zygote was initiated after 7 days of flowering. After 12 days of flowering, perfect seed constituents such as cotyledon, epicotyle and radicle were formed and those were expressed to recognizable level of germinability. After 15 days of flowering germination rate reached higher than 30% and 17 and 21 days after flowering a perfect seed which have 70% or higher germinability were produced. Seed size was ranged between 0.3-0.6 mm and varietal differences were noted in the given seed size range. Under the light treatment, the morphological changes were observed by elongation of radicle after 2 days of imbibition and apparent germination after 3 days of imbibition. But no responses of the seeds imbibed 6 days under the dark condition were observed.

• Journal of Environmental Science International
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• v.30 no.1
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• pp.77-85
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• 2021

This study was carried out to establish optimal conditions for breaking dormancy of Agastache rugosa O. Kuntze seeds. A series of experiments according to seed maturity and treatment with plant growth regulators were performed to improve germination percentage and synchronize germination of the seeds. In addition, it was conducted to test whether the useful effect of seed treatment before sowing leads to healthy seedling and early vigorous growth. The average seed size was 1.85 mm (length) × 0.82 mm(width). The seed size was much smaller than other vegetable seeds. Seeds colorappeared dark brown, the shape of the seeds was oval and the weight of 1,000seeds was 352.8 mg. The optimum germination temperature was 22℃. Light exposure during germination did not affect germination promotion, suggesting that A. rugosa seeds are a kind of dark germinating seeds. Seed dormancy lasted for 40 days after harvesting, and GA3 treatment of dormant seeds could break dormancy. There were significant differences in germination percentage and rate according to the maturity of seeds. The germination percentage of mature seeds was 10 - 18% higher than that of immature seeds, and germination rate was 2 days faster. GA3 treatment during growth regulator treatment improved germinability, but BAP or ethephone treatment did not. The optimal growth regulator concentration of for germination was the combination treatment of 100 mM GA3 ＋ 100 mM BAP.

• Journal of Practical Agriculture & Fisheries Research
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• v.24 no.3
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• pp.25-31
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• 2022

Low-temperature germinability (LTG) is an important trait for the direct seeding of rice in temperate and high altitudes regions. Water temperature of rice fields at sowing season is frequently under 15℃ in Korea, resulting in poor seedlings establishment. The objective of this study was to phenotypically and genetically evaluate 600 rice germplasm composed of six rice subpopulations. In the phenotypic evaluation, aus (AUS) showed the highest visual rating (VR) and germination rate (GR) of 5 and 83.1%, respectively, than other subpopulations. The lowest value of VR (7.1) and GR (53.1%) was observed in aromatic (ARO) subpopulation. Association of the phenotype for LTG with the genotype for qLTG3-1, a major QTL for LTG, and other three SNP markers (LTG_8, qLTG4b-1, qLTG2-6) was conducted. The results suggested that the allele distribution of two markers, qLTG3-1 and qLTG2-6, affects the difference in VR and GR between subpopulations. qLTG4b-1 and LTG_8 were also highly significant with LTG in all subpopulations except that qLTG4b-1 did now show significance in AUS. Therefore, the combination use of these four markers might be effective for evaluation of LTG in rice germplasm.

• The Korean Journal of Mycology
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• v.11 no.1
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• pp.27-32
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• 1983

Five species of the genus Pythium were identified from 91 isolates which were collected from rice seedlings in machine transplanting nursery boxes and paddy fields in Korea. They included P. graminicola complex, P. monospermum complex, P. rostratum complex, and P. ultimum complex. The most frequently found species of the genus Pythium was P. graminicola complex followed by P. monospermum complex. Rice seed germinability was greatly decreased by being infested with P. graminicola complex at nursery box. P. graminicola complex was the most virulent in terms of prohibiting germinations and stunting plants in nursery boxes.

• Journal of Korean Society of Forest Science
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• v.26 no.1
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• pp.23-30
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• 1975

To elucidate the dependability of seed variability determination by tetrazolium, 15 tree species were checked. For the comparison of potential germinability for these tree seeds, x-ray photography and routine germination test in a incubator were implemented. Though there were considerable differences of seed variability in percentage between germination test and tetrazolium test, the judgement by tetrazolium test and x-ray test gave similar results. These findings indicated that tetrazolium test is a reliable method if treated and inferred properly. Solution of 0.25 percent tetrazolium could give a complete colour reaction as well as 0.50 percent solution.

• Asian Journal of Turfgrass Science
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• v.2 no.1
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• pp.70-77
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• 1988

In order to determine and to reduce the differences between biochemical test method for the seed viability with T.T.C. (2, 3, 5. Triphenyl tetrazolium Chloride) reagent and germinator method, the topographical diagram of red colored formazan was carried out in 15-16 parts differences. From this resulted information, the classification of the typical staining reaction given for 3 species were derived into 3-4 parts for the germinable in normal seedling, the same as the following results. 1. Corn (Gram inaceae) * Entier embryo stained in bright red color. * Both extremities of scutellum unstained * Both extremities of scuttlium, coleorhiza and non-critial portions of radicle unstained. 2. Soybean (Leguminosae) *Seed completely stained in red color. *Minor unstained areas on cotyledons. *Extreme tip of radicle unstained; minor unstained areas on cotyledons 3. Radish (Cruciferae) *Seed completely stained. *Minor unstained areas on cotyledons. *Outer cotyledon mostly unstained: inner cotyledon completely stained Extreme tip of radicle unstained: large portion of outer cotyledon unstained.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.308-314
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• 2011

Seed germination and dormancy of three green manure seeds such as hairy vetch, crimson clover and narrow-leaved vetch (Vicia angustifolia L.) produced in Milyang, southern part of Korea were investigated to provide a basic information on the stability of seedling establishment in green manure seeds. In addition, the effect of seed storage duration on the germinability of imported hairy vetch and crimson seeds was also investigated. To determine the seed maturity time of three green manure seeds, the seeds were harvested manually at May 25, May 30, and June 4, and the 100-seed weight, germinability and percentage of hard seed were evaluated. Freshly harvested seeds of three green manure crops were strongly dormant because of hard seed coat. Germination percentage of the three green manure crops varied depending on the seed harvest time ranging from 30 - 52% in hairy vetch, 16 - 35% in crimson clover and 2 - 61% in V. angustifolia, respectively. Of the three crops, crimson clover and V. angustifolia matured early on May 30 to June 4 (around 35 to 40 days after flower) but hairy vetch seed did not mature until June 4 based on the seed germinability. The matured seed of crimson clover and V. angustifolia germinated less than 20% while scarification on seed coat significantly overcome the innate dormancy. On the other hand, the seed germination of hairy vetch and crimson clover was lower under dark than in the presence of light. The germination percentage of the imported hairy vetch and crimson clover seeds showed high with 77 - 79%, 94 - 95%, respectively, but the seed germination significantly declined by 21 - 32%, 30 - 40% after one-year of storage under natural conditions. The seeds germinated only 8 - 13% for hairy vetch but crimson clover did not germinate at all after two years storage. These results indicate V. angustifolia and crimson clover mature at May 30 to June 4 but hairy vetch did not. The imported hairy vetch and crimson clover seeds should be used within one-year after import for stable seedling establishment in green manure-rice cultivation cropping system.

• Horticultural Science & Technology
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• v.18 no.3
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• pp.321-326
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• 2000

To compare germinability of primed seeds with that of water imbibed and nonprimed seeds at different temperatures, percent germination, number of days to attain 50% of the final germination percentage (T50) and mean number of days to germination (MDG) were evaluated at various temperatures ranged from $10^{\circ}C$ to $35^{\circ}C$. Primed carrot seeds in -0.50 MPa PEG 8000 showed higher percent germination at $10^{\circ}C$ or $35^{\circ}C$. Reductions in T50 and MDG values were observed at all germination temperatures when primed with the PEG. The PEG combined with 100 mM $K_3PO_4$ was not as effective as the PEG alone in improving the germinability of carrot seeds. Nonprimed lettuce seeds germinated only 2% at $30^{\circ}C$ or $35^{\circ}C$. However, priming with 50 mM $K_3PO_4$ increased germination to 40% at $30^{\circ}C$ and to 21% at $35^{\circ}C$. In contrast to the single treatment of 50mM $K_3PO_4$, priming lettuce seeds in a mixture of 50mM $K_3PO_4$ and 200 mM $KH_2PO_4$ resulted in a lower percentage of germination, but a significant greater reduction of T50 and MDG. Percent germination was increased when 200 mM $KH_2PO_4$-primed onion seeds and 100 mM $Ca(NO_3)_2$-primed Welsh onion seeds were germinated at $10^{\circ}C$ or $35^{\circ}C$. Combined treatments with $Ca(NO_3)_2$ for onion and with $KH_2PO_4$ for Welsh onion seeds did not improve percent germination, but they significantly reduced T50 and MDG.