• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.89-94
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• 1998

A field experiment was carried out to determine the effects of chemical drying agents at mowing on the field drying rate of alfalfa (cv. Vernal) and rye (cv. Koolgrazer) for hastening hay manuf8cture. In alfalfa; chemicals ($K_2CO_3$ 2% $K_2CO_3$ 3% $Na_2CO_3$ 2% $CaCO_3$, 2% $K_2CO_3$2% + $Na_2CO_3$, 1% only water spray and control) were treated at early bloom stage in 1995. Chemicals ($K_2CO_3$, 2%, $Na_2CO_3$, 2% $CaCO_3$, 2% and control) were applicated at different harvest stages (early heading, heading and bloom) in rye, 1996. The drying rate of alfalfa by $K_2CO_3$ treatment among chemicals was higher than control, and the duration of field dry was shortened by one day with $K_2CO_3$ application, but there was no difference in drying efficiency between $K_2CO_3$ 2% and $K_2CO_3$ 3%. In rye, however, no moisture reduction by chemicals was observed. The days required for field dry were 6, 4, and 3 days at warly heading heading and bloom stage respectively; regardless of chemical drying agents and conbol. The nutritive value of rye hay with chemicals at baling was very slightly higher than control, but there was no significant difference. Also, no difference of hay quality was found among drying agents. In conclusion, $K_2CO_3$can enhance the field drying rate of alfalfa hay, but the drying efficiency was not high, particularly in rye hay. Harvesting at early heading to heading stage was desirable for manufacture of high quality rye hay.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.3
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• pp.188-194
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• 2022

This study was conducted to investigate the forage characteristics of very early-maturing Italian ryegrass (IRG) three cultivars within September, 2021 to July, 2022 in Cheonan, Korea. We used three different cultivars of Italian ryegrass in this study "Greenfarm" "Greenfarm2ho" and "Greenfarm3ho" The results of heading date in this study, "Greenfarm" was recorded 3 days earlier than the other two cultivars, and its lodge tolerance score was the highest among the three. However, in case of plant length, there was no significantly difference in whole cultivars, in addition disease resistance, insect resistance and cold tolerance were not significantly different in three cultivars. The forage productivity of "Greenfarm2ho" was recorded the highest, especially the 1^st harvesting of "Greenfarm2ho" yielded significantly the highest and superior to other varieties. As a result of feed value analysis, three cultivars were generally superior to overseas varieties and in particular, "Greenfarm2ho" was recorded to have excellent value because of the lowest NDF and ADF content. On the other hand, there was no significant difference in crude protein content among three varieties. In case of the monosaccharides content "Greenfarm3ho" had significantly higher glucose content than other two varieties, therefore the "Greenfarm" has advantage for preparing high quality of silage. In contrast, there was no significant difference among three varieties in fructose content.

• Korean Journal of Environment and Ecology
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• v.19 no.3
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• pp.258-268
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• 2005

The objective of this study was to monitor the edge vegetation development process after timber harvesting at deciduous hardwood forest in Seoul National University Research Forest of Baekwoonsan (Mt), Korea The results from the 4th (2001) and 5th (2003) survey for edge vegetation development process after timber harvesting are summarized as follows. The competitive species at the harvested forest edge are Lindera erythrocarpa, Weigela subsessilis, Lespedeza maximowiczii, Lindera obtusiioba, Arajia eiata. There were Lindera erythrocarpa, Ivelgela subsessilis, Staphyiea bumaida as competitive species at harvested forest border between harvested forest edge and harvested interior. And at the forest interior, the competitive species were Lindera erythrocarpa, Lindera obtusiloba. There were differences in the competitive species at the forest edge due to the differences in direction, altitude, and existing dominant species. But Lindera erythrocarpa, Weigela subsessilis were appeared to be a competitive specieg at the southwestern slope (A site) and northeastern slope (B site). After timber harvesting, Sasa borealisshowed a good growth in early days, but showed a tendency of declining with the developing of canopy layer And coverage was generally higher at the Northeastern slope (Site B) than southwestern slop (Site A). The similarity index was lower as the distance from the forest edge becomes farther.

• Journal of Bio-Environment Control
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• v.16 no.4
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• pp.344-347
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• 2007

Optimal date to cover plastic film tunnel for hastening the harvest and increasing the yield in asparagus was studied using 2-year-old 'Green tower' cultivar in Jeju. Plastic film tunnel was covered on January 10 and 21, and February 10 and 25 in 2004. The asparagus spear sprouted on March 3 in the control. They emerged earlier by about 2 to 3 weeks in the plots covered on January 10 and 25 than the control. First harvesting was hastened by 3 weeks in the plots covered on February 10 and two weeks in the plots covered on January 25 and February 10 compared to the control. Yield per plant was the highest in plastic film tunnel covered on January 10 and 25. Early harvesting in february in plastic film tunnel covered on January 10 and 25 were 325 and 333 kg/10a respectively with no significant difference between two treatments whereas yield was low significantly in plastic film tunnel covered on February 10 and 25.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.3
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• pp.247-256
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• 1994

This experiment was carried out to determine harvesting date and cultivar effects on growth characteristics, forage yield and quality of spring sown oats(Avena surivu L.) at the forage experimental field, College of Agricultural and Life Sciences, Swul National University, Suwwn from March 22 to June 20, 1993. The experiment was arranged in a split plot design with three replications. The main plots consisted of the harvesting dates such as early(24 May), mid(8 June) and late(20 June). The subplots consisted of different maturities of oat cultivm such as Speed oat, Cayuse, Foothill, Sv841034 and Magnum.

• Journal of Korea Water Resources Association
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• v.53 no.11
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• pp.961-971
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• 2020

The Intergovernmental Panel on Climate Change (IPCC) reported that the amount of precipitation in South Korea would increase regardless of the reduction of Greenhouse Gas (GHG) emissions. Moreover, the temporal and spatial rainfall variation would also increase in the future. Due to the geographic allocation of Korea, more than 80% of the annual precipitation occurs in the wet season from early July to late September. It is expected that the average precipitation in this period will increase from the Representative Concentration Pathways (RCP) scenario projections. These predictions imply an increased variability of available water resources. Rainwater harvesting system is widely used as an alternative water resources today. This study introduces a RBSN (rain barrel sharing network) as an efficient way to utilize alternative water resources under the RCP scenarios. The concept of RBSN combines individual rainwater harvesting system to a sharing network, which make the whole system more reliable. This study evaluated a RBSN in South Korea composed of four users based on a storage-reliability-yield (SRY) relationship. The study area comprises all 17 provincal areas in South Korea. The result showed a huge benefit from a RBSN in Korea under the historical rainfall condition. Even in the climate change condition, the results showed that a RBSN is still beneficial but the changes in reliability are different depending on provinces in Korea. The results of this study shows that a RBSN is a very effective and alternative measure that can deal with the impacts of climate change in the near future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.277-286
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• 1985

From a series of studies conducted on the local maize lines at the Agr. College of the Chungnam National Univ., a few maize lines with many tillers and ears per plant were identified and tentatively named as MET. The purpose of the study was to evaluate the MET lines, which were selfed for five generations, for silage purpose under the different plant densities. A hybrid, Suwon #19 and a synthetic variety, Puyo #3${\times}$#2, were included for comparison. Plant height at harvesting times showed no significant varietal differences. However, the MET lines were very slow in early plant growth compared to the hybrid or synthetic variety, probably due to inbreeding depression of the MET lines. Total fresh weight at the harvesting times was highest in the MET 1 line. The MET 1 line was about 2,000 kgr. per 10a. higher than the hybrid at the harvesting time. The highest fresh weight was obtained when grown under the plant density of 60 ${\times}$ 20cm. Total dry weight per unit area showed the same tendency as the fresh weight. Total dry weight of MET 1 line was about 2.4 tons per 10a., which was about 10% higher than the hybrid, Suwon #19. As the fresh weight, the total dry weight was also highest in the plant density of 60 ${\times}$ 20cm. The grain yield per 10 are of MET 1 was comparable to the grain yield of the hybrid, especially in the low plant density, 60 ${\times}$ 40cm. The average number of effective tillers of MET lines were 4.5, while the mean tiller number of the hybrid or synthetic variety were none. However, the lodging was one of the problem for growing MET lines. The 100 kernel weight of MET lines was about 9 gr., while the 100 kernel weight of the hybrid or synthetic variety was about 30 grm.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.334-337
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• 2012

A new promising kiwifruit, 'Halla Gold' variety with yellow flesh and being harvested in October, was developed at the Agricultural Research Center for Climate Change, National Institute of Horticultural and Herbal Science, Rural Development Administration, Korea in 2007. This variety was derived from the seedling population crossed between Actinidia chinensis cv. Golden Yellow and A. chinensis cv. Songongu in 1997. It was selected out of 2,971 seedlings. Characteristic trials were carried out from 2001 to 2003. After the selection, adaptability test was also conducted at kiwifruit orchards in Jeju Island from 2003 to 2007. Shoots of 'Halla Gold' sprout slightly stronger than those of 'Jecy Gold' but weaker than 'Hort16A' and the color of leaf is green. Fruit shape is oblong and fruit skin color is yellowish-dark green without hair. The average weight of fruit is 106.3 g. Fruit has a moderate size soft core, yellow pericarp, and fragile and juicy flesh. Soluble solids content is $14.7^{\circ}$ Brix and acidity is 1.4%. The harvesting time is about 10 days earlier than 'Jecy Gold' and about 20 days ahead of 'Hort16A'. The storage life is about 90 days at $2^{\circ}C$. This variety can be recommended for cultivating at low land area bellow 100 m sea level in Jeju Island or under shelter to prevent disease and cold injury.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.164-168
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• 1986

This study was conducted at the forage experiment field of SNU, Snweon to investigate effects of sowing time and seeding rate on growth characteristics, winter survival and dry matter yield of forage rye (Secale cereale L.) as fresh-cut forage. Treatments involved 9 combinations of sowing times (September 8, 28 and October 18) and seeding rates(80, 130 and 180kg $ha^{-1}$). Plant height was not influenced by the time of sowing, but forage rye had a tendency to be taller as increasing seeding rate when sown on September 8 and October 28 and harvested in fall and spring, respectively, Winter survival was reduced by fall harvesting in the plot sown on September 8, however, total dry matter yield was increased by the fall harvesting. Average dry matter yields of 5884, 4993 and 3525kg $ha^{-1}$ were obtained when forage rye was sown on September 8, 28 and October 18, respectively. Dry matter yield was decreased as delaying the time of sowing, but a tendency toward higher yield of forage rye by increasing seeding rate was observed. Yield difference by seeding rates was markedly larger when forage rye was sown on October 18 than September 8 and 28. Based on the results of this study, it appears that the dry matter yield of forage rye could be enhanced by sowing early to late September under upland condition in the middle plain are of Korea. The seeding rates of 80 to 130 kg $ha^{-1}$ and 180kg $ha^{-1}$ would be suitable for early to mid fall and late fall sowings, respectively.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.51-59
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• 2009

Bulb onion cultivation area has been restricted in southern part of Korea to avoid blotting and bulb division. The traditional culture method is transplanting bare-rooted plantlet into the field at the end of summer and harvesting at the beginning of next summer. The hot weather and weak plantlets occasionally causes unstable supply of onions in autumn. In order to enlarge cultivation area and to reduce culture period, long nursery system using plug tray and spring transplanting was tried. Forty cultivars collected from Korea and Japan were nursed using 200-plug tray and transplanted to the field in spring. Marketable yield was not related to the seedling size but lodging time. Cultivar of 'Hamasodachi' was lodged early and resulted low marketable yield. Cultivar of 'Cheonjudaego' was not lodged and yielded high but not in accordance with storability. Generally early lodged cultivars showed low storability. In order to avoid rainy harvesting season, cultivars requires excessive long time for lodging is not recommended for spring culture. Using plug nursery and spring transplanting, we successfully produced marketable onions in 3 months. But immediate using of the harvested onion is recommended. The storability of produced onions showed different result among cultivars, storage of spring onion was not recommended.