• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.85-89
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• 1998

Effect of soil residue paraquat (1,1-dimethyl-4,4-dipyridinium dichloride) on growth of barley (Hordeum vulgare L. cv. Sacheon No.6 and cv. Tapgolbori) and soybean [Glycine max (L.) Merr. cv. Alcheon and Danyeop] was investigated. Changes in soil residue paraquat during the cultivation period and residue amount in the p1ants at harvest were also determined. Experiments were conducted at two paraquat residue conditions; the first was done in an apple orchard soil where paraquat residue recorded 30.2 ppm in 1996, but decreased to about 9 to 9.8 ppm at the time of crop seeding and the second was conducted in the soil fortified to about 27 to 32 ppm paraquat residue. In both conditions, no crop injury due to the residue paraquat was observed and number of emerged seedlings and plant height of the two crops were not affected by soil residue paraquat. Residue amount of paraquat in the plants occurred less than 0.5 ppm detection limit. At the first condition, soil residue paraquat was further slightly decreased for 90 days after seeding, while no great change in the residue level was found at the second condition for 30 days after seeding. The results suggest that no carry-over effect occurs at about 30 ppm of soil residue paraquat and at present crop cultivation in Korean orchard soils are safe with respect to crop growth and paraquat residue in the plants.

• 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.

• Journal of The Korean Society of Grassland and Forage Science
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• v.28 no.3
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• pp.203-214
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• 2008

The overwintering crops, barley, wheat, oat and triticale etc, have been received in korea as high-quality roughage for round-baled silage making as livestock feed. Studies were carried out to evaluated the effects of seed blending on growth, yield and feed value between barley and wheat, triticale and oat, respectively. The results are summarized as follows : The barley was declined in the growth and spike's size as affected by sown as mixed seeding with triticale, but not effected with oat. The total fresh yield were increased by grown as mixed seeding with wheat, triticale and oat, but the dry matter yield were not significantly increased because of the low percentage of dry matter and the decrease of barley's growth. The neutral detergent fiber (NDF) and crude protein content were increased by seed blending, but acid detergent fiber (ADF) and digestible dry matter (DDM) content were decreased. The feed value was improved by seed blending of barley and wheat, but not significant at seed blending of triticale and oat. Because of the flourishing tillers, difference of heading date and abundant leaves of oat, the optimum crop for mixed seeding with barley for increment of forage productivity was oat in middle area of korea.

• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.112-118
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• 1979

This experiment was carried out to evaluate the effect of potassium application level for pasture management in Chungnam area. The results obtained were as follows. 1. The seedling establishment of pasture species was slightly depressed by high potassium application. 2. By increasing potassium application level, the winter hardiness of pasture species increased. 3. The forage yield of pasture species was more increased in legume single seeding than grass single and mixed seeding by higher potassium application. 4. The $K_2O$ content in forage was increased markedly by increasing potassium application level on grass single block. 5. The results obtained from this experiment indicated that potassium application level much effective on the winter hardiness of pasture species and forage yield specially in legume single seeding and adequate amount of potassium would be 20kg per 10a in this area.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.1
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• pp.71-81
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• 1989

Soil erosion was investigated to find out difference in amount of soil eroded from slope land at early stage of young grasses and at later stage with sufficient cover with different slopes. The six experimental plots were formed on 8$^{\circ}$, 10$^{\circ}$, 15$^{\circ}$, 20$^{\circ}$, and 25$^{\circ}$, with 2m width and 20m length located at the Hwak Kok Ri, Chun Sung Gun, Kang Weon Do. The amount of soil eroded and run-off were collected from 1. May 1987. to 30. October 1988, growing with grasses sowed 2. September 1987. The results were as follows : 1. The amount of soil eroded from the plots except 8$^{\circ}$ plot exceeded the allowable soil erosion with 14 ton/ha during the land formuing before establishment of sufficient surface cover with grasses. Therefore, proper soil conservation practice should be recommeneed. 2. The amount of soil eroded increased exponentially with increased slope as 1.24 times for 15$^{\circ}$1.65 times for 20*, and 2.94 times for 25$^{\circ}$, m comparing with standared 10$^{\circ}$ polt. 3. The erosion occurred mainly by high density of rainfall exceeding lOOmm as consecutive precipitation during the raining peried or accompanied by typhoon passing. 4. The significant soil erosion, when the land covering ratio was over 95% after seeding of grass, was recorded only by the single continuous storms over lOOmm of concentrated precpitation, of which amounts were 1/73~/250 of the allowable soil erosion. 5. The amount of soil erosion from the plots with sufficient surface cover with grasses increased as the slope increased however the amounts were small enough to be neglected. 6. Desolation by soil erosion would be minor problem up to the slope of 20$^{\circ}$ when the mountainous area developed to the grassland with sufficient cover. But it could be concerned on the turn to the hare land by the treading of livestocks with the land slope over 25$^{\circ}$. 7. The run-off of rainfall increased by the increament of slope but it was not exponentially increased. 8. The run-off of rainfall after seeding of grass reduced by 20% in comparison with the run-off of rainfall before seeding, which might be due to infiltration of rainfall promoted by the grass roots.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.10 no.2
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• pp.1-15
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• 2007

A variety of revegetation methods are being utilized and developed. However, most of revegetation methods used on highway slopes in Korea are based on foreign-introduced plant varieties to stabilize road surfaces and to administer afforestation for surface covering at an earlier phase. Therefore. it results in various problems. such as failure to achieve harmony with the surrounding vegetation and 10 cause re-denudation of slopes as the foreign-in introduced plant varieties wane out from 2~3 years after hydro-seeding, etc. In addition, some of the revegetation plants seeded in the earlier phase grow excessively high, thus causes successional problems, such as to inhibit the invasion of the secondary vegetation from the surrounding areas, etc. Therefore, in this study, 160 slopes located in the nationwide express highways have been investigated and analyzed in order to produce basic data for restoration of ecological environment in slopes created on a long-term basis by investigating and analyzing locational characteristics of cut and filled slopes in express highways, status of revegetation methods, characteristics of soil and plant-ecological environment. 1. Investigation on cut and embanked slopes in express highways was carried out in the total of 160 locations, which include 108 cut slopes and 52 embanked slopes. As a whole, the most frequently used revegetation method was seed spray, which was found to be used in the total of 55 target slops investigated. 2. Planting method of Wistaria floribunda applied to some of the blasted rock zones was found to cause damages as Wistaria floribunda trailed up the surrounding vegetation and the secondary invaded trees. In order to prevent this, this method must be used only in the lowest parts of large-sized slopes. Also, it will be required to administer continuous management and maintenance in the areas already planted with this plants. 3. The areas of blasted rock and ripping rock slopes were applied with coir net (net + seeding) method. However, many of these areas failed in achieving ground covering. Most areas where revegetation was in progress, they were covered with Eragrostis curvula(Weeping lovegrass) only. In areas with soil, such as decomposition of granite, where afforestation is difficult. In this slopes, soil base must be improved by hrdroseeding with thin-layer vegetation base application methods in order to achieve success in afforestation with native plants. 4. Woody species, rather than herb species, are more helpful in stabilization of slope surfaces. Therefore, it is important to be able to grow and protect woody species on highway slopes. Growth of woody vegetation is most largely influenced by soil depth. Thus, when hydro-seeding woody plants, it is recommended to apply at the upper layer of the slopes, which is capable to sufficiently provide the fundamentals required in plant growth.

• Journal of Gastric Cancer
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• v.7 no.1
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• pp.23-30
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• 2007

Purpose: Evaluating the clinicopathologic characteristics of recurred gastric cancer is essential for early detection of the recurrence and for better clinical outcome. The aim of this study was to establish the patterns of the recurrence, the timing of the recurrence, and the clinical result after recurrence according to the clinicopathologic characteristics of gastric cancer. Materials and Methods: From June 1992 to December 2005, of the 1338 gastric cancer patients who underwent a curative gastric resection, 241 patients who recurred during the follow-up period were selected and their cases were analyzed. The clinicopathologic characteristics of the patients, the time to recurrence after operation and survival were determined retrospectively according to the type of recurrence. Results: For the recurrent group, the numbers of total gastrectomies, advanced stages, lymphatic and/or venous infiltrations, whole stomach cancer cases, large tumors, undifferentiated tumors, and Borrmann type 4 tumors were higher than they were for the non-recurrent group, and the differences were statistically significant. When the recurrence types were classified as peritoneal seeding, hematogenous recurrence, and locoregional recurrence, independent risk factors were female gender, stage III, upper third, and whlole stomach cancer, and undifferentiated- type, diffuse-type, and Borrmann type 4 tumors for peritoneal seeding; early gastric cancer, stage I for hematogenous recurrence; and Borrmann type 1, 2, and 3 tumors for locoregional recurrence. Survival duration after detection of the recurrence was shorter for peritoneal seeding than for hematogenous or locoregional recurrence (7.0 months vs. 9.5 months and 12.5 months). Conclusion: For early detection of the recurrence after curative surgery for gastric cancer, it is important to recognize that the high risk factors for recurrence vary with the clinicopathologic data for the patients.

• Korean Journal of Plant Resources
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• v.25 no.1
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• pp.7-13
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• 2012

This study was conducted to determine the effects of scarification temperature, and sulfuric acid treatments on seed germination of white lotus collected from the Muan districts, Jeonnam in Korea. Without scarification, white lotus seeds were not germinated at all at 15 days after seeding. However, seeds sacrificed at basal parts showed 100% germination rate at $25^{\circ}C$ 6 days after seeding. All the seeds floated (0.90 g) and soaked (1.18 g) in the water were completely germinated. Especially, the lotus seeds soaked in the water at $25^{\circ}C$ showed high germination rate. Seeds treated with 80% sulfuric acid for 40-160 hours were germinated completely within 6 days after seeding. No difference in seed germination rate of white lotus stored up to 0, 12 and 24 months after harvest was observed. Overall results would be useful means for propagation and production of white lotus.

• Korean Journal of Weed Science
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• v.18 no.2
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• pp.106-115
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• 1998

This study was conducted to investigate the effect of oxadiazon, molinate, thiobencarb before seeding on control of red rice and barnyardgrass in water-seeded rice. High application rate plot among oxadiazon treatment plots could observe phytotoxicity symptoms depending on field conditions, but these injury recovered gradually with time. Molinate and thiobencarb application plots at the concentration of 225~400, 210~420g ai/l0a respectively were not observed phytotoxicity. Control of red rice was different according to kinds of herbicides and application rates. Oxadiazon showed higher control performance at the concentration of more than 60g ai/10a. Control effect of molinate and thiobencarb against red rice was enhanced with the increase of application rate, and both herbicides showed satisfactory effect at more than 300g ai/10a. Control of barnyardgrass showed up to 90~100% in all tested herbicides. There was no significant yield reduction by oxadiazon, molinate, and thiobencarb application before seeding in all tested field. In the pot experiment, crop injury, seedling stand, and early growth were more advantageous at time of drainge after one day after seeding than flooding until rooting.

• Korean Journal of Weed Science
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• v.31 no.4
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• pp.355-359
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• 2011

This study was conducted to evaluate the effects of seeding of Vicia tetrasperma and V. hirsuta on the rate of ground cover as well as growth and yield of organic pepper plants in 2008 and 2009. All seeds of both species were gathered from Dangjin, Chungnam in late June of 2006 and stored for two year at room temperature. Capsella bursapastoris, Echinoloa crus-galli, Digitaria ciliaris, and Commelina communiswas were observed as main weeds during the winter and summer, respectively, at the field of V. tetrasperma and V. hirsuta. C. bursapastoris did not affect growth and yield of pepper plants. Seeding of V. tetrasperma and V. hirsuta maintained high percentage of ground cover later in the growing season of pepper plants and reduced significant amounts of weed in 2009. V. tetrasperma and V. hirsuta, therefore, produced more pepper yield compared to that of control but similar yield to the conventional system (polyethylene film).