• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.284-288
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• 2013

This study aimed to get the basic data on the breeding of good varieties in Hypericum patulum Thunberg. The optimum materials, concentration and soaking time were examined to identify the effective approach to induce tetraploid plant by colchicine treatment to cultivate the varieties. For the seed germination rate of seed by colchicine treatment, the higher colchicine concentration was and the longer soaking time was, the more the germination rate decreased. While individuals were germinated in 16 test groups except control group (no treatment group), all the plants were diploid and no tetraploid was induced. For the plant regeneration rate by colchicine treatment on the explant of Hypericum patulum Thunberg that was under in vitro culture, the higher the colchicine concentration increased, the ress the regeneration rate. While total 147 individuals were regenerated in all treatment, when the explant was soaking treatment in more than 0.05% for over 6 hours, tetraploid could be obtained. In the soaking treatment of 0.05% for over 6 hours, tetraploid could be obtained. In particular, for the soaking treatment in 0.05% for 12 hours, 8 tetraploids were induced, which was about 47.1% of the number of plant regenerated. In accordance with the observation on doubling of DNA contents in leaf in order to identify polyploidy, the peak DNA content of G1 phase was 94.5 for diploid and 192.5 for tetraploid. It confirmed doubling of DNA content. Furthermore, the number of chloroplasts per guard cell depending on polyploid was around 10 in diploid and 17 to 19 in tetraploid, which were around 1.7 to 1.9 times as much as diploid.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.273-276
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• 1999

Some metabolites and embryo growth of primed tobacco (Nicotiana tabacum L. cv. ‘KFI09’) seeds were observed during priming. The seeds were primed at 15 and $25^{\circ}C$ for 1, 2, 3, 5, 10 and 15 days in a -0.8 MPa polyethylene glycol 6000 (PEG) solution. The time to 50% seed germination (T$_{50}$) was greatly reduced when the seeds were primed at $25^{\circ}C$ when compared with 15$^{\circ}C$. The $\alpha$-amylase activity and sugars and amino acid contents in the seeds primed at $25^{\circ}C$ greatly increased, while $\alpha$-amylase activity was similar, and sugar and amino acid contents increased slightly in the seeds primed at 15$^{\circ}C$. When the seeds were primed at $25^{\circ}C$, growth of the embryo which was enclosed by endosperm was detected, while the endosperm became thinner as the priming duration was extended.d.

• Journal of the Korean Home Economics Association
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• v.20 no.2
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• pp.85-89
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• 1982

The changes of various lipid content and fatty acids composition of mung-bean sprout during 6 days. The results are summarized as follows 1) The total lipid contents of mung-bean sprouts are generally decreased during growing. 2) On T.L.C. gram, triglyceride contents are decreased and free fatty acids and sterol are increased with time. 3) The ratio of unsaturated fatty acids to saturated fatty acids U/S are increased by six times after 4 days of mung-bean germination. 4) The contents of palmitic acid as main fatty acid in the mangbean but oleid, linoleic acid were increased after 2 days, 4 days, 6 days. 5) Total lipids from mung-bean sprouts contained fatty acid in order of linoleic acid, oleic acid. 6) The content of essential fatty acid are rich in 4 days.

• Journal of Practical Agriculture & Fisheries Research
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• v.12 no.1
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• pp.21-27
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• 2010

The objective of this study was to determine the effects of "Green-one" organic nutrient on mycelial growth and fruiting of P. ostreatus. The dilution concentrations of "Green-one" was treated as follows. There was control, 100, 200, 400 concentrations. That treatments were treated with step of each mycelial growth step. The best of growth steps was mycelial scratching step. At that time, DPI(Day required for primordial formation after inoculation) was shortened for 1 day. Valid germination stipe are 15 pieces, 3 pieces more than control. Stipe length and stipe diameter was long each 4mm, 3mm more than control. Pileus size is shortened than control. Yields per one bottle(g/850cc) was 146g increased 6.5% than control 137g/850cc.

• Korean Journal of Environmental Biology
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• v.41 no.4
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• pp.608-615
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• 2023

The morphological features of germling cells were examined to identify an unspecified resting cyst (described as Cochlodinium cf. polykrikoides-like resting cyst) in the Korean coastal area. LSU rRNA gene sequences were also obtained from a strain established from the germling cells. The resting cysts isolated from Korean coastal sediment were characterized as being brown in color, having a large dark-red body, and fibrous lobed ornaments. The germling cells were ellipsoidal with an irregular outline and had an open comma-shaped ASC (apical structure complex), a wide and deep cingulum, and a deep sulcus. These morphological features were consistent with those of previously described harmful dinoflagellate Pseudocochlodinium profundisulcus. The molecular phylogeny revealed that the germling cells and P. profundisulcus were conspecific. Based on these morphological and phylogenetic data, this study documents the occurrence of P. profundisulcus in a Korean coastal area for the first time.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.2
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• pp.131-136
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• 2022

This study was conducted to evaluate the efficacy and phytotoxic of crop desiccant treatments on the seed production of Italian ryegrass (Lolium multiflorum Lam.) in Gimje and Buan, South Korea. Here, Italian ryegrass was treated 7, 10, and 14 days before harvest (DBH) and no difference in fresh weight, 1000-seed weight, germination rate, and seed yield was observed compared to the untreated control in the standard dose and double dose for seven DBH. However, the standard dose and double dose on the 10 DBH and 14 DBH had a lower 1000-seed weight, germination rate, and seed yield compared to the untreated control. In pesticide persistence analysis, the permitted standards were not exceeded in the seeds and straw according to the treatment time and concentration. These results suggest that the treatment effect and stability of Italian ryegrass can be expected if treated within seven DBH. However, it seems that crop desiccants should be used after considering grain ripening and weather to minimize loss of seeds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.2
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• pp.123-128
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• 1986

The characteristics such as characters of seed, fruit and endosperm, development of embryo, dehisced and germination rate of seeds which harvested at 10 days intervals from 20 days to 60 days after pollination were determined to clarify the optimum time for seed production of ginseng. The sizes of length, width and thickness of fruits, seeds and endosperms investigated on 20 days after pollination were not largely different from those that harvested after 60 days. But the weights of fruits and seeds were increased along with the delay of harvesting time. The seeds which harvested from 30 to 60 days showed comparatively high dehisced and germinated rates, especially 40 days in dehisced rates and 50 days in germinated rates. The embryos were rapidly grown in early stage. Lengths of the embryo on 20 days after pollination were approximately grown to 30 ${\mu}{\textrm}{m}$. And after 30 days pollinated, embryos were not only more rapidly grown to 213 ${\mu}{\textrm}{m}$ but also cotyledon premodia were developed in this time and completely formed after 40 days.

• Journal of Korean Society of Forest Science
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• v.96 no.3
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• pp.307-316
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• 2007

Yellow poplar (Liriodendron tulipifera L.) has low germination rate relatively other species, so the seedling production of Yellow poplar is a hard task. Accordingly this study was conducted to determine the optimal germination conditions for healthy seedling production and to promote survival rate after afforestation. Gemination percentage was examined at different media and seed covering materials using planting flats in the greenhouse. The best germination percentage was observed in sand for media and compound soil for covering materials. But it was time to transplant, seedlings became a poor character (i.e. height, root length, number of root, dry weight) in sand for media. In order to produce healthy seedlings, each different medium was compounded with TKS-2 (this is a gardening bed soil.) in the ratio 1:1 (v/v.), and compared two conditions. Quality of seedling was better than not mixed TKS-2 into each medium. Transplanting seedlings from greenhouse to nursery grew up rapidly 2 months later (early in August~early in October). Growth amount during two months corresponded to 85.6% and 71.3% in total growth amount of height and diameter at root collar, respectively. In the case of the competition-density effect on yellow-poplar seedlings, direct seedling produced the maximum 35 standard seedlings above 8 mm of root collar diameter per $m^2$, while transplanting seedling produced the maximum 64 standard seedlings per $m^2$. And produced seedlings of two way were significantly different rootlet while axial root and lateral root was not significantly different.

• Journal of Korean Society of Forest Science
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• v.112 no.3
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• pp.352-362
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• 2023

Harvest time is one of the most important determining factors of seed quality, especially for species that produce seeds over irregular and long-term periods, such as Larix kaempferi. A cone collection plan must be established to increase seed production efficiency and stable mass production. We investigated seed qualities such as seed efficiency, germination rate, and T₅₀ (germination speed), with 7 or 8 cone collection times at a clonal seed orchard of L. kaempferi in Chungju between 2021 and 2022. A multivariate analysis was then performed for the collected data. In early August, decreases in the moisture contents and browning of cones were observed. These were followed by a decrease in germination rate, with a peak at the end of September, but no clear trend was observed. The later the cones were harvested, the better the seed vigor (T₅₀). However, the seed yield and efficiency decreased owing to increases in seed scattering and the number of insect-damaged seeds. As a result, the optimal time of seed harvest for the seed orchard was in early August. To produce uniform seedlings, insect damage must be reduced through timely control and harvest cones in early September. This shows that the degree of browning and moisture content of cones can be used as indicators of the timing of cone collection in L. kaempferi seed orchards.