• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.64-69
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• 1998

This experiment was conducted to investigatd the variation of some apearance chemical components at National Honam Agricultural Experiment Station in Korea. the treatements consisted of five transplating times, form May 5 to July 5 at 15-day interval , and six cultivars ; two early-maturing, two mid-maturing and two latematuring cultivars. The results showed that the variatio of grain appearance such as length-wide ratio was not significantly different in early -maturing cultivars, but mid-and late-maturing cultivars made slightly a round shape of grain in case of early transplanting. Percentage of complete grain was found to be high at transplanting of MAy 20 inearly-maturing cultivars and on June 5 in mid-and late-maturing ones. PERcentage of existed embryo after milling showed high at early transplanting of May 5 for early -maturing cultivars, and at the late transplanting of June 5 in early and late maturing one. The chemical components of rice grain showed high in protein , lipid,ash and amylose content inthe earlier transplanting, and also revealed high in carbohydrates, magnesium and potassium in the later transplanting of all cultivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.4
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• pp.291-298
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• 1996

This study was carried out at Crop Experiment Station in 1993 and 1994. The objective of this study was finding out variation of growth and yield of corn according to maturity. Hybrids of corn used in this study were early maturing corn Comet80, Elite90, Royaldent IOOT, Royaldent T$\times$llO, P3525, P3394, medium maturing corn Royaldent 120T. and late maturing corn Jungbuok, P3144W. G4743. Stalk height, leaf number, ear weight, stover weight, and TDN yield of early maturing corn were linearly increased with prolonged maturity in 1993 growing season. Leaf number, and stover weight of early and late maturing corn were linearly increased with prolonged maturity in 1994 growing season. But ear weight of late manuring corn was not increased as much as that of early manuring corn with prolonged maturity. Increase of total DM and TDN yield of late maturing corn was due to stover weight increase compared with ear weight increase of early maturing corn. Leaf number and stover weight were highly correlated with silk (Growing Degree Days) GDD.

• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.146-151
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• 1998

A study was carried our to investigate the characteristics of physico-chemical components palatability of cooked rice accoring to different transplanting time. The treatments were consisted of five transplanting time, from May 5 to July 5 at 15 -day intervals, and six cultivars ; two early-maturing, two mid-maturing and two late-maturing cultivars which are clearly identified by evaluation of cumulative temperature and growth duration from seeding to heading of rice plants. In gelatinization characteristics of rice grain, alkali digestion value was low in the earlier transplanting regardlessof maturing types. Initial pasting temeprature maximum viscosity and breakdown as amylogram charcteristics were high at the transplanting of June 5. The palatability of cookedrice was evaluated that early-maturing cultivars were much better in early transplanting than in late transplanting . The optimum transplanting time for palatibility was the periods from May 5 to 20 in early maturing varieties, May 20 to June 5 in mid-maturing and June 5 to June 20 in late-maturing ones at Honam district in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.37-42
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• 1995

This experiment was canied out to study the effects of seeding and harvesting dates on the growth of early and late maturing rye(Seca1e cereale L.) varieties at the forage testing field of S.N.U., Suweon, from September 1986 to May 1989. Leaf and tiller numbers of rye per plant were increased with earlier seeding date, but no difference in the tiller numbers was found between harvesting dates of early and late maturing rye varieties. Tiller dry weight of an early maturing rye veriety, Wintermore was higher than that of a late maturing rye variety, Kodiak when sown as early as September. Maximun leaf area index(LA1) and leaf area index duration(LA1D) were achieved with earlier seeding and early maturing rye varieties. A higher correlation between the maximum LA1 or LAID and dry matter accumulation of rye varieties was observed in this experiment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.201-206
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• 2004

This experiment was performed to evaluate the agronomic characteristics and dry matter yields of the early maturing cultivars(c.v.'Koolgrazer', '9909,' 'Ol-homil' and 'Jlee select') the medium maturing cultivar(c.v. 'Homil 22') and late maturing cultivars(c.v. 'Danko', 'Kior', 'Amilo' and 'Spooner'.) Seeds were sown on October 3, 2002 and October 8, 2003, respectively at the Livestock Experiment Farm of Keimyung College, Seongju, Kyeongbuk Province. Forage rye was harvested on April 22, 2003 and April 23, 2004, respectively. The height of early maturing cultivars were higher than that of late maturing cultivars at the harvest. Fifty percent heading date of the early maturing cultivar was on April 14 and that of late maturing cultivars were on April 24. In the first year, dry matter(DM) yield of 'Jlee select' was significantly the highest in among all cultivars(p < 0.05). DM yield of early maturing cultivars were higher than that of medium and later maturing cultivars. In the second year, DM yield of '9909' was significantly the highest in among all cultivars(p < 0.05). The early maturing cultivar of 'Koolgrazer' and 'Ol-homil' were similar and 'Jlee select' was low, late maturing cultivar of 'Danko', 'Kior', 'Amilo' and 'Spooner' were lower than early maturing cultivar. According to the results obtained from the study, it is suggested that the early maturing cultivar would be recommendable for fall sown rye for double cropping forage production.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.27-34
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• 1997

This experiment was carried out to determine growth characteristics, dry matter (DM) yield, seasonal yield distribution and nutritive value of early- and late maturity orchardgrass, 1990 to 1992. The cultivars used in this study were Potomac, Hallmark (early maturing cultivar) and Lidacta, Rancho (late maturing cultivar), and a mixture plot (Potomac 25% + Hallmark 25% + Lidacta 25% + Rancho 25%) was involved. The seeding rate was 20 kgha in all treatments. Plant height of Potomac and Hallmark was longer than that of Lidacta and Rancho. The dates of initial heading and 50% heading of early maturing cultivars (Apr. 30 and May 10) were 10 days earlier than those of late matuing cultivars. Potomac and Hallmark were upright, and Lidacta and Rancho were semi-upright type, and severe disease and weeds (30 ~ 40%) were observed at Lidacta plot. On an average of three years, the DM yields of Potomac (10,549 kglna), Hallmark (10,435 kg) and mixture (10,356 kg) were significantly (P<0.05) higher than those of Rancho (9,457 kg) and Lidacta (8,218 kg). However, seasonal yield distribution of late maturing cultivars was better than that of early maturing cultivars. The contents of crude protein, crude fat, crude fiber, nitrogen %ee extract, aude ash, neutral detergent fiber, P, K, Ca, and Mg were not significantly different between cultivars, but higher aude protein yield was found at Potomac, Hallmark and mixture plots. Based on the above results, it may be concluded that early maturing cultivars for high productivity, late maturing cultivars for seasonal yield distribution, and seeding of mixture andlor separation of early- and late maturing cultivars are recommended. Also Lidacta was a not promising cultivar due to low productivity, severe disease, and high weeds development.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.4
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• pp.316-323
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• 1994

In order to reduce the problems from the presence of rye crop residues in maize establishment and yield, and also to improve the growth, productivity and nutritive value of rye(Seca1e cereal L.). an experiment was canied out to determine the variety effect of rye on the forage production system and the eft'ect of seeding and harvesting dates on the production and quality of rye. 'This experiment was conducted at the forage testing field of S.N.U., Suweon, from September 1986 to May 1989. Heading date of an early maturing rye variety, Wintermore. was earlier 10 days than that of a late maturing rye variety, Kodiak. A 15-days delay in the seeding dates of early and late maturing varieties of rye tended to delay the heading dates of the rye varieties for 3 and 4 days, respectively. Dry matter and in vitro digestible dry matter yields were markedly increased with earlier seeding date. Before 20 April, the DM and IVDDM yeilds of an early maturing rye variety, Winterrnore. were higher than those of a late maturing rye variety, Kodiak. However, no such a trend was found between the early and late maturing varieties of rye after 27 April. Less than 35% of ADF was recorded until the harvesting dates of 13 and 27 p r i l for early and late maturing rye varieties, respectively, but less than 46% of NDF was maintained until the harvesting drtte of 13 April for botg varieties. Based on the results obtained from this experiment. it may be concluded that the most desirable forage production from corn-rye double cropping system is to advance the seeding time of rye toward the first 10 days of September as well as harvesting time toward the first heading stage with an early maturing rye variety.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.970-977
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• 2006

Forage oat (Avena sativa L.) is grown extensively in a double-cropping system on dairy farms. Four oat varieties ('Swan', 'Targa', 'Foothill', and 'Nugene') were evaluated for forage production and forage quality during two growing seasons (spring and autumn) at two locations (central and southern region) in South Korea. The heading stage of four oat varieties was observed during spring, but the autumn season did not produce heading until harvest time except for the 'Swan' variety (early-maturing variety). The heading stage of 'Swan' in both locations was earlier compared to other varieties. The four varieties were resistant to both foliar disease and insects. Lodging resistance was higher during autumn except in 2002 at the central region, and late-maturing varieties ('Foothill' and 'Nugene') have lower lodging resistance. Dry matter (DM) content was significantly different between varieties (p<0.001). Comparing different varieties, 'Swan', an early-maturing variety, was highest in DM content. In DM, total digestible nutrients (TDN) and crude protein (CP) yield, the yield of oat varieties in the southern region was higher than in the central region, and forage yield of the oat varieties in the spring season was higher than during the autumn season. The DM and TDN yield showed significant differences between oat varieties. The CP content of oats grown in the central region (Cheonan) was lower than oats grown in the southern region (Daegu), and the spring season produced oats with lower CP compared to the autumn season. Among the four oat varieties, the CP content of late-maturing varieties was higher than the Swan variety (early-maturing variety). The acid detergent fiber (ADF) and neutral detergent fiber (NDF) contents were higher for the varieties grown in Cheonan and during the spring season. The ADF and NDF contents of late-maturing varieties were lower than the early-maturing variety. TDN and relative feed value (RFV) were higher for the varieties grown in Daegu and during the autumn season. Late-maturing variety had higher TDN and RFV than early-maturing variety. Our study showed differences in forage production and forage quality of oats grown in different locations, seasons and varieties. Forage quality as well as forage production was better in the southern region than in the central region. Forage quality was better during autumn, but forage production was better during spring. Late-maturing variety had better forage quality than the early-maturing variety. Therefore, late-maturing varieties are more suitable for use in the southern region.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.2
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• pp.120-129
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• 2004

This study was carried out to develop new varieties with early maturing and large fruit size in the Korean native dogwood (Cornus kousa) for woody landscape plants from native sites or cultivated area. The results are obtained as follows; We selected strains with early maturing and large fruit. size from the habitats from 2000 to 2003. ‘SKK 2-1’ had 4.0cm of fruit size while 2.0 cm of native variety. In addition, ‘SKK 2-2’, ‘SKK 2-3’, ‘SKK 2-4’, and ‘SKK 2-5’ with large fruit and early maturing were preliminary selected from the habitats. In the preliminary selections, ‘SKK 2-1’ was finally selected as new early maturing variety with large fruits in 2003. New early maturing variety with large fruit size, C. kousa var. ‘SKK 2-1’ was selected from 200 plants of 5-year-old seedlings in C. kousa in 5-12 Nung wean ri Goo sung myun Yong In, Kyung gi do, Korea in 2000. Their fruits were colorized in September 18, 20∼25 days earlier than October 7 of native varieties. Its fruit diameter is larger than 4cm. Its fruit weight was 5 times as heavy as native cultivars grown in Korea. This useful characters were still inherited after grafting. However, characteristics of growth, leaf, flower, and flowering period were not different from those of native varieties. Therefore, it was very promising landscape woody plant, having large fruits in early fall season. The rooting rate of Korean dogwood was high by the IBA treatment. The optimum date for softwood cutting was on June 25 ∼ July 25 when the rooting rate was more than 80%. In addition. Korean dogwood was easily propagated by grafting. Therefore, new early maturing variety with large fruits, C. kousa var. ‘SKK 2-1’ is easily propagated by softwood cutting or grafting and then is a promising cultivar as a woody landscape plant.

• Korean Journal of Remote Sensing
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• v.28 no.6
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• pp.653-660
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• 2012

This study classified paddy fields according to rice varieties and monitored temporal changes in rice growth using SAR backscatter coefficients (${\sigma}^{\circ}$). A growing period time-series of backscatter coefficients was set up for nine fine-beam mode RADARSAT-1 SAR images from April to October 2005. The images were compared with field-measured rice growth parameters such as leaf area index (LAI), plant height, fresh and dry biomass, and water content in grain and plants for 45 parcels in Dangjin-gun, Chungnam Province, South Korea. The average backscatter coefficients for early-maturing rice varieties (13 parcels) ranged from -18.17 dB to -6.06 dB and were lower than those for medium-late maturing rice varieties during most of the growing season. Both crops showed the highest backscatter coefficient values at the heading stage (late July) for early-maturing rice, and the difference was greatest before harvest for early-maturing rice. The temporal difference in backscatter coefficients between rice varieties may play a key role in identifying early-maturing rice fields. On the other hand, comparisons with field-measured parameters of rice growth showed that backscatter coefficients decreased or remained on a plateau after the heading stage, even though the growth of the rice canopy had advanced.