• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.1
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• pp.41-54
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• 2006

In case of leaving artificial slopes resulting from large-scale constructions, there may be secondary damage caused by soil loss due to erosion and collapse. Furthermore, slope-restoring constructions have a few problems such as monotonous landscape and difficult succession of secondary vegetation due to reckless use of exotic grass, despite attaining the initial purpose of revegetation. To settle this problem, selected plants deemed to be proper for revegetation were used on one of thin vegetation base methods, CODRA SYSTEM, and made seeding mixture experimental plots considering germination rates differing in each season. Native herbs, native shrubs and exotic herbs contents were increased by 30% and 50% respectively, centered on seeding quantity(30g/$m^2$) used as design standard in the seed spray method, in order to figure out proper quantity for revegetation in each season.

• Progress in Superconductivity and Cryogenics
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• v.1 no.1
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• pp.1-6
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• 1999

The microstructures of top seed mult processde $\textrm{YBa}_2\textrm{Cu}_3\textrm{O}_7$.$\delta$ single crystal were studied. Although shape of the seed was not faceted. the growth shape of Y123 single crystal was faceted. It was observed that Y211 phases were trapped in specific spaces of the faceted region. From the microstructural investigation. it was suggested that the segregation of Y211 is due to the difference of growth rates in crystal direction. When a single crystal was grown by the single seed with stepped multi surfaces. a microstrue was grown from multi-seed. The microstructure show the possibility of multi-seed growth. Corn kernel like structure without Y211 phase was observed and seemed to be formed by the diffusion reaction between Y211 phase in crystal and liquid wetted on the crystal. the diagonal line on Y123 crystal was observed that it was formed by the corn kernel like structure.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.1
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• pp.41-46
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• 2022

To investigate the domestic seed production potential of Italian ryegrass, it was sown in autumn in the southern region and harvested in the spring of the following year to investigate the productivity and quality of seeds and straw. Italian ryegrass (Lolium multiflorum Lam.) 'GreenCall' variety was sown in Jinju, Gyeongnam in the fall of 2020 with three seeding rates (20, 30 and 40 kg/ha). The experiment was arranged consisted of a randomized block design with three replications. The ryegrass was sown on October 17, 2020, and the harvest was on May 31, about 60 days from the heading stage. The heading stage of Italian ryegrass was April 28, and there was no difference among treatments. Plant height was significantly shorter in the 40 kg/ha seeding treatment group, and there was no significant difference in the remaining treatments. The resistance of lodging, disease, and cold did not show significant differences among treatments. Spike length and number of seeds per spike were highest at 20 kg/ha seeding amount, and there was no difference in the remaining treatments. The seed yield was the highest at 1,956 kg/ha in the 20 kg/ha seeding rate, and there was no difference in the 30 and 40 kg/ha seeding rates. The dry matter content of seeds and straws was 45.60 and 41.83% on average, and there was no significant difference among treatments. The amount of remaining straw after seed harvesting was found to be 7,689 kg/ha on average on a dry basis, and it was high in the 40 kg/ha sowing area, but there was no significant difference among treatments. According to the above results, it was found that it is most advantageous to sow at 20 kg/ha when producing Italian ryegrass seeds through autumn sowing in the southern region.

• Korean Journal of Weed Science
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• v.15 no.1
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• pp.19-29
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• 1995

The effect of seeding depth on the growth, mesocotyl elongation and herbicidal response of rice(Oryza sativa L., Japonica type, cv. "Tongjin") and barnyardgrass(Echinochloa crus-galli Beauv. var orizicola Ohwi.) were studied in greenhouse experiments. Barnyardgrass growth as affected by different water depths was briefly tested. Rice and barnyardgrass were broadcast in soil into Oem, 1cm, 2cm and 3cm in seeding depth under dry direct-seeded condition. Butachlor(N-(buthoxymethyl)-2-chloro-N-(2,6-diethylphenyl) acetamide) at dose rate of 1800g ai/ha and thiobencarb(S-[(4-chlorophenyl)methyl] diethyl carbamothioate) at dose rate of 2100g and 4200g ai/ha were soil applied to them at 5 days after seeding. At 10 days after seeding, plants harvested to examine their growth as affected by seeding depth. Root length and shoot fresh weight of rice untreated was greatest in 1cm- and 3cm-seeding depth, respectively, however, mesocotyl did not elongate. While plant height of barnyardgrass grew regardless of seeding depth and water depth, but root length was greatest in 1cm-seeding depth of dry condition and reduced with increased water depth. And mesocotyl was elongated in only dry condition and its length increased with increased seeding depth. At 10 days after application thiobencarb applied pre-emergence inhibited plant height, and shoot fresh weight of rice in only 0cm-seeding depth under dry condition whereas was unaffected in above 1cm-seeding depth, similar to untreated control, and ever increased root length and root fresh weight of rice. On the other hand, shoot, root and leaf growth of barnyardgrass was, severely inhibited regardless of application rates and seeding depths. Reduction of shoot growth by treatment of herbicide was significantly greater than that of root growth. Consequently, reduction of barnyardgrass growth by treatment of thiobencarb did not be associated with seeding depth and mesocotyl elongation as affected by different seeding depth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.2
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• pp.131-136
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• 2005

This study was conducted from March 21 to July 7 in 2004 at JeJu Island to investigate the influences of seed-ing rates (4, 6, 5, 10 and 12 kg/10a) on creeping bentgrass vegetation. The result obtained were summarized as follows; plant height was getting longer as seeding rate increased from 4 to 12 kg/10a, Although it was no significance from 10 to 12 kg/10a. Root length, Minolta SPAD-502 chlorophyll reading value, leave and root weight increased as the plant height increased. The degree of land cover and density of creeping bentgrass also increased as seeding rate increased from 4 to 12 kg/10a, and the degree of land cover and density of weed decreased. The number of weed species on decreased as increasing of seeding rate. Then ranking of the dominant weeds were Digitaria adscendens, Chenopodium album var. centrorubrum md Poa annua (at 4 kg/10a seeding rate), Digitaria adscendens, Chenopodium album var. centrorubrum and Stellaria media (at 6 kg/10a seeding rate). Chenopdium album var. centrorubrum, Poa annua and Digitaria adscendens (at 8 kg/10a seeding rate), Digitaria adscendens, Chenopdium album var. centrorubrum and Steilaria media (at 10 kg/10a seeding rate), Chenopdium album var. centrorubrum, Digitaria adscendens and Stellaria media (at 12 kg/10a seeding rate). These results showed that the optimum seed-ing rate is 10 kg/10a for growth of creeping bentgrass in volcanic ash soils of Juju island.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.2 no.3
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• pp.25-31
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• 1999

The differences in seed germination rates of Korean Native Plants were observed depending on the harvest years, the seed companies, the storage periods, the drying methods and the plant morphological types. The seed germination rates were changed significantly by the harvest years and the seed companies in all 4 species tested. The seed germination rates were decreased after 1 year storage at $4^{\circ}C$ in all 8 species tested and three of them did not germinate at all. A rapid drying method at $35^{\circ}C$ with a convection oven was not suitable for Chrysanthemum spp., but there were no significant changes of germination rates in Aster spp. The germination rates were decreased more at seeding in soil than at lab. test with Dicotyledon but no significant changes with Monocotyledon. Especially, the germination rates of fine seed on 5mm soil covering treatment were significantly decreased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.1
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• pp.34-44
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• 1996

Several major agronomic traits of 4 isogenic lines for tillering(Kindred, Morex)were investigated under the different seeding rates and seedling mortality grown in the pots. The normal-tillering phenotypes had higher grain yield(46％) and leaf area index(56％) than their uniculm isogenic counterparts. The assortment rate(69％) and 1,000 grain weight(27％) in uniculm type were greater than the normal type. Uniculm plants were earlier in heading(4∼8days) and maturing(2∼3 days) dates compared with their counterparts. The grain yield was fitted to linear regression, ranged 0.659g to 0.5g per spike number. On increasing the seedling mortality rates, the grains per spike and 1,000 grain weight were slightly decreased, but the grain yield per plot was decreased markedly because of decrease of spikes per plot. The assortment rate, leaf photosynthetic capacity and reproductive tiller number were increased with increase of seedling mortality. The grain yield was largely dependent on the number of spikes per plot on occurrence of seedling mortality. For the uniculm genotypes to be introduced and bred into a present leading variety, the isogenic lines were precisely tested in the open field for a couple of years.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.1
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• pp.78-83
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• 1986

To obtain the information about the reasons why hulless barley varieties generally have poor germination and emergence rate in the field, hulled and hulless isogenic lines were bred and used. The germination rates of hulless isogenic lines were 4-6 percent lower than those of hulled lines at artificial precipitation treatment, and seriously dropped down at 5 day precipitation treatment. As the thresher rotation speeds up 600 to 1,000 rpm, the differences of germination rate were 10 percent in hulled, but 22 percent in hulless lines. Also emergence rates of hulless lines became seriously low at deep seeding. The emergence rates of hulless isogenic lines became low in the order of deep seeding, high speed thresher, and rain-fall. These results suggest that barley breeders especially for hulless varieties should plan their breeding programs to improve the emergence rate or seedling vigour in the field.

• Journal of Biosystems Engineering
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• v.35 no.5
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• pp.330-335
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• 2010

Soybean (Glycine max Merr.) and corn (Zea mays L.) transplanting has increased because soybean and corn crops cultivated by the direct seeding method were often damaged by wild birds. The purpose of this study is to develop a seeder to sow soybean (Glycine max Merr.) and corn (Zea mays L.) in a plug tray. In order to find out design factors for a metering device of the seeder, metering characteristics on metering hole size and roller speed were experimentally investigated. Soybean (cv. 'Daewon') and corn (cv. 'Mibaekchal') were used as a materials for testing the seeder in this experiment. The metering hole size of roller suitable for Daewonkong and Mibaekchal was determined. Daewonkong was suitable for hole diameter of 10 mm and hole depth of 5.5 mm, and Mibaekcal was suitable for hole diameter of 9 mm and hole depth of 5.5 mm. At a brush length of 4 mm, one grain seeding rates of Daewonkong and Mibaekchal was 99% and 93% respectively. By inducing Mibaekchal to the hole by swing, one grain seeding rate of that increased from 91.9% to 97.7%. When roller speed is 4 m per minut, seeding efficiency of prototype was 110 sheets per hour.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.1
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• pp.1-8
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• 1996

The objective of this study is to obtain the basic data for investigating the effects of organic reserves on winter survial or regrowth yield. Forage rape (Brussicu napus L.) was sown at 10 day> interval from Sep. I to Nov. 1. Field-grown palnts were sampled on the before wintering (Dec. 4) and on the wintering period (Jan. 16) to analyze the nitrogen and non-structural cahohydrate reserves. The rate of winter survival and regrowth yield were also measured in the spring of next year. On the before wintering, the dry matter yields from the plots sown on Sep. 1, Sep.11 and Sep. 21 were 860, 596 and 260 kg/lOa, respectively. No. harvest was canied out on the plots sown after Oct. 1 because the growth state was not enough to cut. Both of nitrogen and starch contents per plant significantly increased as the seeding date was later. On the wintering period, the contents of nitrogen reserves in roots were 176.8. 120.1, 71.7, 84.0, 72.1, 45.3 and 33.3 mg/plant, those of starch reserves were 199.0. 55.8, 21.8, 92.6, 86.5, 36.4 and 29.0 mglplant, resepctively, in the plots sown on Sep. 1, Sep. 11, Sep. 21, Oct. I, Oct. 11, Oct. 21 and Nov. 1. The rates of winter survival were 40, 36, 33, 85, 87, 59 and 49% and regrowth yields were 161, 86, 65, 520, 451, 121 and 33 kgD.M/lOa, respectively, in each plots. 'Ihese results clearly showed that seeding date has a close influence on the level of organic reserves and forage yield, and that the possibility of continuous utilization on the before and alter wintering is extremely limited by seeding date.