• Weed & Turfgrass Science
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• v.4 no.3
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• pp.268-277
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• 2015

Organic fertilizer preparation was developed with organic materials to improve growth and qualities of cool-season turfgrass species. Organic fertilizer preparation were contained with essential macronutrient elements and organic matter for growth of cool season turfgrass. Four preparations of organic fertilizers were tested on creeping bentgrass (Agrostis palustris Huds) cultivar Penn-A1 and Kentucky bluegrass (Poa pratensis L.) mixed cultivars (Midnight 33%, Moonlight 33%, and Prosperity 33%) by one time application on fifty days after sowing. Two species of cool season turfgrasses were evaluated on turfgrass coverage, growth on NDVI (Normalized Difference Vegetation Index) and qualities from fall season to spring season in sod producing farm. It were found significantly difference found on turfgrass coverage, turf color, chlorophyll contents and growth increase on two species of cool season turfgrasses. Turfgrass coverage, chlorophyll content, turf color and growth increase of organic fertilizer preparation were significantly increased on creeping bentgrass cultivar and Kentucky bluegrass mixed cultivar for six time investigation in spring season. These results may indicate that the use of some preparation is beneficial for sod producing sod and turfgrass management.

• Applied Biological Chemistry
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• v.28 no.3
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• pp.182-186
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• 1985

In order to determine the optimum sowing date of peanut in the middle part of Korea, peanut's 100-grain-weight and physico-chemical compositions for peanut cultivars such as runner (Yeoju landrace), semi-spanish (Suweon No. 15) and spanish types (Wasedairu) to different seeding date which planted at interval of ten days from May 5 to July 4, in 1981, was carried out. The 100-grain-weight and crude fat of peanut were increased from May 5 to May 25, but after that decreased. And the 100-grain-weight of peanut was great in order of Wasedairu, Suweon No. 15 and Yeoju landrace. The highest amount of crude fat was seen in peanuts which was sown at May 25 and May 15. Unsaturated fatty acids are composed of $80{\sim}85%$ of oleic and linoleic acid, but saturated fatty acids are constituted of $10{\sim}15%$ of palmitic acid and $1{\sim}5%$ of stearic and arachidic acid. Composition ratio of fatty acid in peanut was changed greatly according to sowing date. According to the late sowing date linoleic and palmitic acid were increased but oleic acid was decreased, respectively.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.365-371
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• 2012

This study was carried out to know the characteristics of flowering and bearing fruit, the optimum period, regions and methods for seed harvesting, the optimum temperatures for seed storage and germination, and the optimum period for sowing at nursery bed and seedling transplanting of Valeriana fauriei Briquet. The flowering and bearing fruit of Valeriana fauriei was developed from the before-year root. Optimum period for seed harvest of Valeriana fauriei was from late July to middle August, and optimum areas were the high elevated areas over 500 m above the sea level as Jinbu-myeon, Pyeongchang-gun, Gangwon-do. Using of net-bag for seed harvesting was the effective method to gather the full ripe seed, and bagging of net-bag was necessary from the season of middle May that was the flowering middle-stage. Germination rates don't show the difference among the different temperatures of storage as approximately 41% at $-20^{\circ}C$, $2^{\circ}C$ or $20^{\circ}C$ of seed storage temperatures. The optimum temperature range was in $15{\sim}30^{\circ}C$ for seed germination at nursery bed. The optimum period for seed sowing at nursery bed was the late February, and the optimum period for seedling transplanting was the middle April.

• Korean Journal of Soil Science and Fertilizer
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• v.23 no.4
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• pp.275-280
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• 1990

In order to obtain the basic informations on the reasonable fertilization and soil management systems for a high soybean yield, both soybean leaves and soils were collected from 24 soybean-cultivated fields in central area of Korea, and analyzed. For this study, soybean leaves and soil were sampled together in July of 1988(growing season), and soil alone in October of 1988 (harvesting season) and April of 1989(sowing season) at each sampling site. The results might be summarized as follows: 1. The soil pH ranged between 4.8 and 6.8. and the pH after harvest decreased to 5.4 which compared with the pH 5.7 of growing season. 2. Both the 1N KCl extractable Al and the 1N $NH_4OAc$ extractable Al in soils were inversely correlated with the soil pH. the former concentration was negligible above pH 5.8. 3. The soil total-N and Bray 1-P after harvest were lower than those of growing season. The Bray 1-P's of sample soils were very high irrespective of sampling time. 4. The exchangeable Ca and Mg in soils even after harvest varied little whereas the exchangeable K decreased with time. 5. The N content in soybean leaves was not correlated with soil total-N, but highly correlated with the K content in soybean leaves. The Mg content in soybean leaves was also highly correlated with Ca content in suybean leaves and exchangeable Mg in soils.

• Korean Journal of Medicinal Crop Science
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• v.3 no.3
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• pp.165-172
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• 1995

This study was carried out to investigate effects of poly-ethylene (P. E.) films mulching according to the different sowing date on growth and yield of Scutellarja bakalensjs G. In sowing date at Apr. 20, the number, length, diameter and yield of root was increased. In black P. E. film mulching, the growth of shoot and root was better and weed control was more effective than open field cultivation during hot season. Therefore dry weight of root was increased by 5% at Apr. 20 as compared with Apr. 1 in P. E. film mulching and that of black P. E. film mulching cultivation was increased by 13% as compared with transparent P. E. film mulching cultivation. But in nonmulching cultivation, the yield of root was increased at Apr. 1

• Journal of Environmental Science International
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• v.18 no.4
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• pp.463-471
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• 2009

A study on vegetation in the Mangyeong River and Dongjin River basins and the surrounding regions of the Saemangeum Reclaimed Land was conducted in a series of efforts to determine the expected ecological changes in the salt marshes, to restore their vegetation, to explore the restoring force of halophyte, to examine the community mechanism and, ultimately, to rehabilitate marshy land vegetation along the lakeside, coastal dune and salt marshes of the Saemangeum Project Area. The findings of the study may be summed up as follows: Five species such as Suaeda japonica, Salicornia herbacea, Atriplex gmelini, Aster tripolium and Suaeda asparagoides that are mostly distributed in the estuary of the Saemangeum Reclaimed Land were analyzed to examine the mechanism of halophyte to maintain their community. To find out the strategies of plants for survival and the cause of forming community structure, a research was made as for appearance ratio of biomass, root lengths and germination. With regard to biomasses of halophyte, the biomass of Suaeda japonica increases rapidly, while Salicornia herbacea adopts a strategy of unstable growth pattern by which the biomass increases slowly in parallel with its slow speed of growth since initial appearance of young sapling. In contrast, Suaeda asparagoides, Atriplex gmelini and Aster tripolium choose to adapt themselves to environment promptly by being transformed into life form of annual or biennial plant, a pattern that is presumed to be favorable and stable for survival in the later stage of growth. In short, there is a sharp distinction among the 5 species: i.e. Suaeda japonica that begins to grow fast in the length of surface and underground section but slows down from the mid-stage on; Salicornia herbacea that grows slowly in the beginning step but starts to step up from the middle onward; Atriplex gmelini and Aster tripolium growing slowly in the initial stage but fast later on; and Suaeda asparagoides that turns from the constant growth in the beginning to rapid growth in the later period. The outcomes of the analysis into status of growth and influencing factors of Suaeda japonica in the sowing field that is most widely prevalent in the Saemangeum Reclaimed Land as a sort of ecological pioneer in the salt marshes showed that the average size of grass lands, density and number of individuals increase in the natural sowing field as well as in the plowing field regardless of their physical as well as physico-chemical features of the soil as the season progresses from June to October of a year.

• Applied Biological Chemistry
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• v.23 no.4
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• pp.246-250
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• 1980

The effects of two Cytozyme complexes, Crop Plus and Seed Plus, applied to rice (variety: Jinheung) were evaluated during the 1980 rice growing season. Primary objectives were directed to determine the effects of rates, timing and method of application of the products on the yield of rice. For the Seed Plus test, seed was soaked in the diluted Seed Plus solution(1 : 100) for 24 hours just prior to sowing. The Crop Plus was diluted to 1 : 12 for seedling treatment. Seedling roots were immersed in the diluted solution for 3 hours before transplanting. Crop Plus spray applied at the rates of 450ml/ha or 900ml/ha when rice plants were in the panicle initiation, heading or tillering stage respectively to compare the effects of rates and timing of application. The weather was not favorable for rice growth during the growing season except the tillering stage. The foliar spray at the tillering stage was more effective than the spray at the panicle initiation, and the rates of 900ml/ha showed better results than 450ml/ha. Combination of seed treatment and foliar spray increased grain yield by 16% over untreated control plots.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.295-302
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• 1997

The study conducted to know the effect of growth and yield by different weed control duration using by 'chalok 1 ho', waxy maize, at Suweon in 1995. The emergence of weed and growth and yield of waxy maize on weedy check and 10, 20, 30, 40, 50, 60, 70, 80, and 90 days weed control and whole season weed control during cultivation summrized as follows; 1. Chenopodium album, Echinochoa crus-galli, Persicaria hydropiper and Panicum bisulcatum emerged as major weeds and dominant weed was Chenopodium album. 2. The number of emerged weeds grouped by mophologically ordered broad leaf weeds, grass weeds and sedge weeds. 3. 30 days weed control duration from the sowing effect to silking stage and 40 days weed control duration from the sowing decreased stem length, ear length, ear weight, number of plant, and number of ear. 4. The yield of weedy check, and 10 days weed control from the sowing showed no yield and 20, 30 and 40 days weed control from the sowing decreased to 76, 64 and 33 %, individually. 5. The yield loss of waxy maize on weeds can be prevent by 40 days weed control duration from the sowing.

• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.1
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• pp.55-70
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• 2001

It was unusual crop weather for 1998 and 1999 compared with normal in Korea. The consecutive days of the optimum ripening period for rice plant that had daily mean temperature 21~23$^{\circ}C$ for 40 days after flowering, increased with long anomalies in 1998~99. The air temperature during ripening period was much higher than the optimum temperature and lower sunshine hour than norm in the local adaptability tests of newly developed rice lines during those years. In response of rice cultivation to warming and cloudy weather during crop season, the yield shall be decreased. Most scientists agree that the rate of heating is accelerating and temperature change could become increasingly disruptive. Weather patterns should also become more erratic. Agrometeorologists could be analyzed yearly variations of temperature, sunshine hour and rainfall pattern focused on transient agroclimate change for last a decade. Rice agronomists could be established taking advantage of real time agricultural meteorology information system for fertilization, irrigation, pest control and harvest. Also they could be analyzed the characteristics of flowering response of the recommended and newly bred rice cultivars for suitable cropping plan such as cultural patterns and sowing or transplanting date. Rice breeders should be deeply considered introducing the characteristics of basic vegetative type of flowering response like Togil rices as prospective rice cultivars corresponding to global warming because of the rices needed higher temperature at ripening stage than japonica rices, photoperiod-sensitive and thermo-sensitive ecotypes.

• Korean Journal of Organic Agriculture
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• v.29 no.4
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• pp.601-612
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• 2021

This study was conducted to evaluate the appropriate sowing method and mixture seeding rate on germination of Kentucky bluegrass (Poa pratensis L.) and white clover (Trifolium repens L.). The experimental design includes two sowing methods and six mixed seeding per each method: BT₁:BP₀ (broadcast seeding; B, Trifolium repens; T, Poa pratensis; P), BT₁:BP₂, BT₁:BP₃, BT₃:BT₁, BT₂:BP₁, BT₀:BP₁ and ST₁:SP₀ (spot seeding; S), ST₁:SP₂, ST₁:SP₃, ST₃:ST₁, ST₂:SP₁, ST₀:SP₁. The germination was the highest for both species when the seeding rate was higher than other species. In overall, the germination of white clover was higher and faster than Kentucky bluegrass. Two plots, BT₂:BP₁, ST₁:ST₂, were retained the balanced proportion of the germination rate. Therefore, It was suggested, for maintaining the balanced field, it is better to seed white clover twice Kentucky bluegrass on broadcast seeding and Kentucky bluegrass twice white clover on spot seeding. In regard of sowing method, broadcast seeding is better than spot seeding in terms of increasing the germination. It is necessary to supplement the result for real application by long-term monitoring.