• Journal of Aquaculture
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• v.20 no.2
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• pp.81-84
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• 2007

We studied two research items that can be undetermined issues in the artificial seed production of the Japanese scallops, Patinopecten yessoensis, batch-specific quality of the reproductive outputs and nursery acclimation, in the embayed waters of Yangyang, Gangwon, Korea. The first batch of the spawner showed better results in terms of survival, growth, and resistance against parasitic ciliate infection over the second batch that was obtained in 5 days after first batch from the same spawner. The early attached spats directly placed in the farming ground (the unacclimated) were resistant against the water current of the open environment, by showing survival of about 80% for a month, a normal survival compared with other results. However, the spat survival during the nursery acclimation was significantly lowered in comparison with that in the unacclimated condition (P<0.01). We discussed the research results of the two items, particularly focusing on their availability for mass seed production for aquaculture in the Korean coastal waters of the East Sea (Sea of Japan).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.1 no.1
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• pp.42-45
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• 1963

In a plant breeding program, an efficient selection of desired characters in a population is important. Generally, many agronomic characters in a given population are determined by polygenes and quantitatively inherited. In practice, the genetic relationship between two observed characters which are undoubtedly subjected to the environmental influence is difficult to identify. In recent years, many workers have attempted to understant the genetic relationship between characters in terms of genotypic correlation, and the knowledge thus gained should furnish many important and useful information for the planning of breeding, selection, and interpretation of the result. The genotypic correlation is the result of pleiotropy, linkage of genes(2, 3, 5, 6, 8) and natural or artificial selection(4). The purposes of this study were to estimate genotyric and phenotypic correlations between all possible pairs of nine characters. and to seek certain characters which may be useful as indicators of certain important agronomic characters. Weber and Moorthy(10), Johnson et al. (5) and Sheth(7) found that in general, the genotypic correlations were higher than the phenotypic correlations. Weiss et al. (11) obtained significant positive correlations between maturity and oil content, maturity and low protein content, and high protein content and low oil content. Weber and Moorthy(10) reported the positive genotypic correlations between flowering and maturity, yield and maturity, yield and plant height, yield and seed weight, and negative genotypic correlations between maturity and oil content, and oil content and seed weight. Johnson et al. (5) studied the genotypic and phenotypic correlations among 24 characters and concluded that selection based entirely on a long fruiting period, lateness, heavy seed, low protein, high oil and resistance to lodging would be effective in increasing yield. Sheth(7) found the following positive associations among characters; height and maturity, yield and lodging, low protein content and high oil content, and yield and low protein content. Hanson et al.(1) also reported high negative correlation between seed yield and protein content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.1
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• pp.112-116
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• 1999

In theprevious Hizikia cultivation, holdfasts were threw into the sea after harvesting in May; the young thalli(5$\~$10cm in length) of Hizikia are annually collected from natural bed by seed collectors for the cultivation, resulting in a ruined natural populations. Therfore, the reuse method of holdfasts by regeneration capability of Hizikia fusiformis, was investigated. The effects of emergence on the growth of regenerated thalli from holdfasts over 6 months of outdoor culture from May to November, 1995. The vegetative growth from the holdfasts was good under the emergence of 3hrs/day on the air than 0, 1 and 2hr/day. The regeneration of holdfasts was determined by measuring total length, number of stipe and weight. The growth was facilitated under the exposure condition of 1$\~$3 hrs/day on the air. Outdoor cultivation for the comparsion of to artifical natural seeds were conducted from December 1995 to May 1996. There was no significant differences(0.05< P) between the two kinds of seeds. Therefore, artificial seed maybe used as a replacement for the natural seed in Hizikia cultivation. From the results, an useful method was established to obtain young fronds for the cultivation using the reuse method of holdfast, to conserve the natural population of Hizikia.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.195-201
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• 2000

This study was conducted to investigate the suitable conditions for seed germination of Rosa davurica PALL. In the characteristics of the fruit and seed of Rosa davurica, fruit length and width was 1.3cm and 0.9cm , respectively, and seed number was eighty-nine. Artificial and low temperature storage at 4$^{\circ}C$ increased the rate of split achene pericarp until 46.6% and storage at 15$^{\circ}C$ incubator decreased the rate of split achene pericarp (10.5%). The rate of seed germination of split achene pericarp in control at 15$^{\circ}C$ was 90% and of non-split achene in GA$_3$100ppm at 15$^{\circ}C$ was 36.8%. Average germination day of split achene pericarp seeds in GA$_3$150ppm at 2$0^{\circ}C$ was 4.2 days and non-split achene pericarp in GA$_3$100ppm at 2$0^{\circ}C$ was 7.3 days. Seed germination was not different between various concentrations of GA$_3$ treatments in split achene pericarp seeds but the rate of germination was more reduced in high concentration of 200ppm. Only the treatments of GA$_3$ was increased germination rate at 4$^{\circ}C$ and immature seed of Rosa davurica.

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.3
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• pp.35-46
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• 2023

It was in the 1982 that artificial seed production research for olive flounder (Paralichthys olivaceus) farming was first conducted in Korea (Currently, National Institute of Fisheries Science, Fish Breeding Research Center). In 1985, fertilized eggs were obtained from natural olive flounder adapted to land tanks, and artificial seed production technology was established and fertilized eggs were distributed. In the late 1980s, halibut aquaculture began to prosper in land-based tank farming in Jeju Island and Busan's Gijang region, where water temperatures are relatively high in winter. Currently, aquaculture is being carried out all over the country, centering on Jeju Island and Wando, Jeollanam-do. However, olive flounder farming, which started with a small group in the 1980s, reduced genetic diversity through inbreeding over generations, resulting in side effects such as slow growth, reduced resistance to disease and environmental conditions. In order to solve these genetic problems of farmed olive flounder in Korea, the Fish Breeding Research Center of the National Institute of Fisheries Science introduced a wild-caught parent fish group to the existing aquaculture group from 2003 to 2004. Genetic diversity was secured and KingNupchi with fast growth and improved body shape was developed. In this study, the current status of breeding technology development of olive flounder, a major aquaculture breed in Korea, is reviewed and future research directions are suggested.

• Korean Journal of Environment and Ecology
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• v.7 no.1
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• pp.10-21
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• 1993

Artificial acid rain (pH 3.0, 4.0 and 5.0) and ground was treated on the seeded pots of 4 species to examine its effects on germination and survival rate, seedling growth and contact angles on needle surface. Artificial acid rain was prepared by diluting sulfuric acid with ground water and ground water (pH 6.5) was used as control. Artificial acid rain was sprayed to seeded pots two or three times per week for growing season, one times per week for winter seasons. About 5mm of artificial acid rain was treated each time from early April, 1991 to early October, 1993. Germination and survival rate, soil acidity, seedling growth and contact angles on the needle surface were measured and compared among the treatments. The results were summarized as follows ; Artificial acid rain might have positive effects on growth-related characteristics of the seedlings in the first and second year of acid rain treatment, and the effects were differed among four species. All growth-related characteristics of the seedlings in third year, however, decreased with decrease of pH values of artificial acid rain. This was considered to the results of acidic accumulation over soil buffer capacity. Needle injury and biomass (defoliation) was correlated with the pH values of artificial acid rain, and this character might be a good criteria for early diagnosis of acid rain injury. The differences of soil acidity were significant among the treatments for all species. Contact angles between needle surface and water droplet decreased with decrease of pH values of artificial acid rain. Measuring and comparing contact angles might be very good criteria for early diagnosis of acid rain injury.

• Journal of Life Science
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• v.16 no.2 s.75
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• pp.352-356
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• 2006

Quantity of protein, amino acid, and sugar leaked from seeds was greater as the viability of seeds was dropped by the time elapsed of seed aging treatment. In the seeds with the artificial aging treatment for 20 days, 35.8 mg of protein was leaked on the 4th day after soaking, which was 6.9 times higher than that of control. Leakage of amino acid was also higher from low quality seeds treated with the aging treatment. In the seeds with the aging treatment for 20 days, $36.5{\mu}g$ fig of sugar was leaked on the 4th day after soaking, which was 2.8 times higher than that of control. The leakage of inorganic compound was higher from the low quality seeds, and leakage of total protein, amino acid, and sugar. According to .the quantity of leakage, water soluble compounds, which can be used for the assessment of seed quality without any destruction, were protein and potassium. Germination rate and percentage of seeds were dropped with the seed aging treatment, and the seed viability could be recovered by priming treatment. This phenomenon was very clear when the low quality seeds were germinated at low temperature.

• Korean Journal of Plant Taxonomy
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• v.52 no.4
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• pp.226-234
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• 2022

The study aims are to examine the characteristics of artificial and natural hybrids between Viola albida var. albida (= albida, from below) and V. albida var. chaerophylloides (= chaerophylloides, from below), and to confirm if hybrids could be fertile and make populations in their native habitats. The 1st filial (= F₁, from below) leaf shape produced by artificial crossing between albida and chaerophylloides was the same as that of V. albida var. takahashii (= takahashii, from below), and F₁ bore also both chasmogamous and cleistogamous flowers. F₁ seed number was 9.6 per cleistogamous pods, which was remarkably less than the average of 38.2 for albida and chaerophylloides, but the germination rate was all similar. The leaf type of self-crossed 2nd offsprings (= F₂, from below) showed all leaf types found in the Viola albida complex, but the ratio of chaerophylloides leaf type was relatively low. Individuals whose F₂ leaf type was restored to albida produced an average of 31.4 seeds per capsule, meaning that fertility was restored. On the other hand, individuals of F₂ takahashii leaf type come to fruition a low average of 10.4 seeds per capsule, which is similar to that of takahashii. The results of crossbreeding experiment, where is their native habitats, were similar to that of laboratory. Both albida and chaerophylloids in Mt. Bulmyeong distribute extensively, but takahashii make a small population only in places where albida and chaerophylloides grow together. Summarizing the above results is suggesting that the speciation of takahashii was done by hybrid between albida and chaerophylloides, and these have been maintained with relatively small population by cleistogamous capsules.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.4
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• pp.81-90
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• 2005

This study aimed to address problems and suggest solutions in applying seed mixture design criterior of the slope revegetation works according to "The guidelines of Slope revegetation design and construction" proposed by the Ministry of Construction and Transportation. To do this, the planting thickness was set to be the same 2cm while the composition of seeds was made different, which was planted in artificial slopes and fields. The main results were summarized as follows. In the test, when applying the provisional standards of the plant mixtures proposed by the Ministry of Construction and Transportation, tree seeds and native plants were found poor coverage effect in the early stage in all test plots due to introduced grasses. This was because introduced winter grasses which grew well in the early stage, could grow densely, so it might hamper the growth of other plants. Therefore, it was found desirable that standards for seed mixing should be adjusted down by 10% and the ratio of introduced grasses in the mixture should be lowered to 25% while native plants should increase to 20-25%.

• Research in Plant Disease
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• v.30 no.1
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• pp.13-19
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• 2024

In July 2022 and 2023, black mold symptoms were observed sporadically on fruits of sweet pepper (Capsicum annuum) plants grown in a greenhouse located in Suwon, Korea. The incidence of black mold on the fruits was 5-24% (average 14.8%) in variety SP-504 (yellow and elongate type) and 1-8% (average 5%) in variety SP-505 (red and round type) investigated. Four single-conidium isolates of Alternaria sp. obtained from the diseased fruits were identified as Alternaria alternata based on the morphological characteristics and molecular phyogenetic analyses. The isolates were tested for pathogenicity to sweet pepper fruits of varieties SP-504 and SP-505 through artificial inoculation. The isolates mostly induced large lesions on fruits of the two varieties in the wound inoculation, but only two isolates small lesions on fruits of the variety SP-504 in the non-wound inoculation. No lesions formed on fruits of the variety SP-505 in the non-wound inoculation. The pathogenicity tests revealed that susceptibility of sweet pepper fruits to the disease differs between the varieties. The symptoms induced by pathogenicity tests with the isolates were similar to those observed on fruits from the greenhouse investigated. This is the first report of A. alternata causing black mold on sweet pepper fruits in Korea.