• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.5
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• pp.373-380
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• 2004

The production of sweet (su) and super sweet corns (sh2) has been economically feasible in Korea in recent years. Major factors limiting super sweet corn production are low germination and low seedling vigor. Since seed quality is closely related to seed maturity, the optimum harvest time for the seed production of sweet and super sweet corns was studied and the quality of seeds with varying maturities was investigated in 2001 and 2002 cropping seasons. The parents of the sweet corn seeds were Hybrid Early Sunglow and 'Golden Cross Bantam 70' and those of super sweet corn were Xtrasweet 82 and 'For­tune'. Seeds were harvested at 21, 28, 35, 42, 49, and 56 days after silking (DAS). As the seeds developed, seed weight of sweet corn increased and the seed moisture content decreased faster than that of super sweet corn. Germination rates of sweet corn seeds harvested 21 and 28 DAS at $25^{\circ}C$ and emergence rates in the cold soil test were significantly lower than those of seeds harvested after 42 DAS in both years. Although the germination rates of super sweet corn seeds with varying maturities showed similar patterns as sweet corn seeds at $25^{\circ}C$, the emergence rate of super sweet corn seeds in cold soil test continuously increased with seed maturity. This suggests that seed quality of super sweet corn should be tested in a cold soil test to estimate field emergence. As the seeds developed, leakage of total sugars and electrolytes from the both sweet and super sweet corn seeds decreased up to 42 or 49 DAS. The $\alpha-amylase$ activities of both sweet and super sweet corn seeds increased with seed maturity from 21 to 35 or 49 DAS depending on genotype and year. The optimum harvest time for the seed production of sweet corn was 42 DAS and 49 DAS for super sweet corn considering emergence rate and plumule dry weight in the cold soil test, leakage of sugars and electrolytes from the seeds, and $\alpha-amylase$ activity.

• Research in Plant Disease
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• v.12 no.1
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• pp.1-4
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• 2006

During visiting North Korea from 2001 to 2005, I have had a few chances to observe and discuss several North Korean scientists for the seed production program and also, the occurrence of potato pests. Healthy seed production, especially in the early generations, e.g. the production of virus-free starting materials as well as in vitro pre-basic seeds (G0) by hydroponics and basic seeds under netted houses according to her new national seed potato program of Academy of Agricultural Science, Pyongyang, North Korea, has been done well so far. Some major pests occurred, however, in the early generations such as pre-basic seed (G0) in greenhouse, basic seed (G1) in screenhouse, foundation seed-I (G2) and even ware potatoes in the fields are Phytopitthora infestans, Spongospora subterrunea, Ralstonia solanacearum, Pythium spp. and some viruses such as Potato virus X, Potato virus Y, Potato leafroll virus, and also larger potato ladybeetle, greenhouse whitefly and potato tuber moth. Therefore, the success of healthy seed production in North Korea will be thoroughly depended on the pest control and the multiplication of virus-free seed stocks in the isolated areas, especially where no infected potatoes are grown.

• Korean Journal of Weed Science
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• v.18 no.1
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• pp.42-47
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• 1998

The experiment was conducted to study the growth, developmental pattern, and seed production of Commelina benghalensis L. grown from four seed types; large and small aerial seeds, and large and small underground seeds. Plants from the four seed types differed in growth rate. Based on dry weight and leaf area, plants from large underground seeds emerged and grew faster in the first 2-4 weeks after seeding(WAS) but plants from small aerial seeds grew faster during the 4-6 WAS; thereafter, there was no significant difference in growth rate among plants from the four seed types. Based on seed production, plants from large aerial seed produced more seeds(1473) than those from small seeds(1006). Small aerial types represented 75-77% of the total seed production, large aerial seed 21-23%; only 2-4% were underground seeds. The results suggest that the plants from large underground seeds might have better competitive ability Than those of small aerial seeds during the early growth stage due to faster germination and higher dry matter production.

• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.247-252
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• 1995

This study examines the effects of the planting time of mother bulb and mulching materials for the seed production of onion on the amount of seed production, and the following results are obtained : Growth, bolting rate, flowering rate, floret numbers per scape and fertilization rate are best in the case of the seed production under transparent vinyl mulching between Sept. 10 and Sept. 25, and seed yield per plant and seed yield per 10a are increased in the case of the seed production under transparent vinyl mulching between Sept. 10 and Sept. 25, so it is found that it is appropriate to plant the onion mother bulb under the transparent vinyl mulching between Sept. 10 and Sept. 25 in the southern areas of Korea.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.19 no.2
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• pp.71-81
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• 2016

This text was experimented and investigated the optimum production time and germination characteristics of seed that collect in Korean Chungnam, in order to offer the basic informations for slope restoration and revegetation using Poaceae plant. Optimum time of seed production was mid-late October of Miscanthus sinensis, Pennisetum alopecuroides, early November to late October of Themeda triandra var. japonica and M. sacchariflorus, and mid November of Phragmites communis. Epiphytic amount of seed full ripe was the most times in mid October of M. sinensis, P. alopecuroides and M. sacchariflorus, early November of T. triandra var. japonica, and mid November of P. communis. Seed rate of maturity was the highest times in early November of M. sinensis, P. alopecuroides and M. sacchariflorus, and mid November of T. triandra var. japonica and P. communis. Germination rate by seed collection time was the highest times in early October of M. sacchariflorus, mid October of T. triandra var. japonica, early November of M. sinensis and mid November of P. communis. Germination days by seed production time was the shortest times in early November of M. sinensis and M. sacchariflorus, mid November of T. triandra var. japonica and P. communis. Optimum temperature of germination was $20{\sim}25^{\circ}C$ in M. sinensis and P. alopecuroides, $25^{\circ}C$ in T. triandra var. japonica, and $25{\sim}30^{\circ}C$ in P. communis.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.2
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• pp.156-156
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• 2001

The objective of this study was to investigate the effects of nutrients and culture conditions on morphology during the seed culture of C. acremonium ATCC 20339 Morphological factors such as hyphal length number of tips number of arthrospores were observed to investigate the relationship between seed morphology and CPC production. During the time course of seed culture, hyphal length was shortened and the number of arthrospores increased rapidly On the other hand the number of tips deceased rapidly and this was closely related to the hyphal length Mixed nitrogen sources of 3% solybean meal and 1% cotton seed flour were determined as the proper organic nitrogen sources, in terms of the morphological factors in the seed culture. This fact was proven in batch culture for the production of Cephalosporin C. It was also found that a proper agitation speed enhanced the morphological differentiation of C. acremonium ATCC 20339, thus improving the production of Cephalosporin C.

• The Korean Journal of Ecology
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• v.14 no.4
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• pp.361-370
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• 1991

The cone and seed production of pitch pine were investigated at two areas(songtan and yangdong) located in kyounggi province. Bymeans of formulas derived from both the regression analysis between the number of seeds and cone length, and between d2·h and number of cones, cone and seed production were estimated. The correlation coefficient value between the number of seeds and cone length was high(r=0.6134). The cone and seed production of pitch pine has a high relationship to the variables-dbh, tree aga , and height of tree. The cone production of pitchpine forest estimated by the formula log(o+s+y+c)=0.581 log(d2·h)-1.317 was 965,832/ha in 1985∼1986, 850,852/ha in 1986∼1987 at songtan, and 462,794/ha in 1985∼1986,916,965/ha in 1986∼1987 at yangdong.

• Korean Journal of Environmental Agriculture
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• v.36 no.1
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• pp.36-42
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• 2017

BACKGROUND: Yuza seed by-product has been produced in a large amount from the agricultural farms in the southern area of Korea. It has been mostly abandoned after commercial process for the production of juice, jam and tea. The study on the reuse of the yuza seed by-product has received much attention as a bio-resource material for the production of active compound in agriculture. METHODS AND RESULTS: Insecticidal rhamnolipid-producing Pseudomonas sp. EP-3 was grown in mineral salt media with the yuza seed by-product at 2, 20, 50 and 100 g/L. The growth of EP-3 was accompanied by a increase in insecticidal activity against green peach aphid. The highest insecticidal activity was observed when EP-3 was grown in the medium containing 50 g/L of the seed sample, producing approximately 996 mg/L of rhamnolipid at 96 h. Palmitic acid, stearic acid, oleic acid and linoleic acid were determined as the major fatty acids of the seed sample. The EP-3 cultures grown on the fatty acid mixture extracted from the seed sample showed a aphid mortality similar to that of cultures grown on the seed sample. The EP-3 cultures grown on 50 g/L of the seed sample showed aphid mortality more than 90% under greenhouse conditions. CONCLUSION: This study suggested that the yuza seed by-product may be used as a renewable material for microbial production of rhamnolipid against green peach aphid.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1196-1200
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• 2007

Eight feeds (mixture of wheat straw and oil seed cakes in 3:1 ratio) were evaluated for methane emission and fermentation pattern with buffalo rumen liquor as inoculum in an in vitro gas production test. The cakes tested were groundnut cake (GNC), soybean cake (SBC), mustard seed cake (MSC), cotton seed cake (CSC), karanj seed cake expeller extracted (KCEE), karanj seed cake solvent extracted (KCSE), caster bean cake expeller extracted (CBCEE) and caster bean cake solvent extracted (CBCSE). The gas production (ml/g dry matter) was significantly higher with SBC and MSC followed by CSC, GNC, KCSE, KCEE, CBCSE and was the lowest with CBCEE. Methane emission was significantly lower with KCEE, KCSE, CBCEE, CBCSE (20.32- 22.43 ml/g DM) than that with SBC, GNC, CSC (27.34-31.14 ml/g DM). Mustard seed cake was in-between the two groups of oil cakes in methane production. In vitro true digestibility was highest with SBC followed by GNC, CSC, MSC, KCSE, KCEE, CBCSE and CECEE. Ammonia nitrogen level was positively correlated with the amount of protein present in the cake. Total holotrich protozoa were significantly higher with SBC, whereas, large spirotrich protozoa tended to be lower than with other cakes. The counts of small spirotrich and total protozoa were similar with all the cakes. Total volatile fatty acid production and acetate to propionate ratio were significantly higher with SBC and significantly lower with KCEE as compared to the other cakes. Among the conventional oil cakes tested in the present experiment (GNC, SBC, MSC and CSC), mustard seed cake-based feed produced the minimum methane without affecting other fermentation characteristics adversely.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.211-217
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• 1992

This experiment was conducted over a 3-year period (1990-1992) to evaluate the production and quality of orchardgrass (Potomac)-red clover (Kenland) mixture when orchardgrass + red clover mixture was sown at seed rates of 20+0. 18+2, 16+4, 14+6 and 12+8 kg/ha. Total herbage dry matter, crude protein and digestible organic matter production and organic matter intake were markedly affected by increasing rcd clover seed rate, those increased with increasing red clovcr seed rate due to the cnhancernent of red clover percentage of total herbagc in all 3-year. but significant differences occured between the orchardgrass alone and orchardgrass-red clover mixture with a seed rate of 4,6 and 8 kg/ha red clover (P<0.01). But on the other hand increasing red clover seed rate increased red clover percentage in total herbage, the mean red clover percentage of total herbage at the last cutting ranged from 54 to 65% in first year. 58 to 60% in second year, and 62 to 69% in third year, particularly it was observed that red clover was sown at seed rates of 6 and 8 kg/ha for red clover sown dominated strongly as the cutting times were progressed. Considering the maintenance of good botanical composition balance and the enhancement of production and quality of herbage, the optimized seed rate for orchardgrass-red clover mixtures, 16 kg/ha orchardgrass and 4 kg/ha red clover seems to be considered adequate.