• Korean Journal of Agricultural Science
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• v.45 no.3
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• pp.355-363
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• 2018

This study was conducted to investigate suitable rice cultivars for various rice based cropping systems in a paddy field in the Yeongnam plain area. Thirteen rice cultivars (5 early, 3 medium and 5 mid-late maturing cultivars) and three transplanting dates (June 5, June 25 and July 5) were evaluated in this study. The mid-late and early maturing cultivars for the July 5 and June 25 transplanting headed before August 30 which is the safe heading date in the Yeongnam plain area, ranging from Aug. 26 - 28 and Aug. 18 - 23, respectively. The safe harvest time of rice for double and triple cropping systems should be before the middle of October for the cultivation of the succeeding winter crops. The rice yield was the highest for the June 5 transplanting regardless of the rice cultivars, and it gradually decreased as the transplanting date was delayed from June 5 to July 5 due to a decrease in the spikelet numbers per panicle number and in the ripened grain rate. In contrast, the other yield parameters that include the panicle number per $m^2$, the 1,000-brown rice weight, and the ripened grain ratio were not significantly affected. The result indicates that based on the milled rice, heading time and harvest time, a medium maturing cultivar (Haiami and Samdeog) would be applicable to a winter barley/wheat, garlic/onion-summer rice double cropping, while a mid-late cultivar (Saeilmi, Saenuri and Hyunpoom) would be suitable for a spring potato/waxy corn-summer rice double cropping in the Yeongnam plain area. On the other hand, an early maturing cultivar (Unkwang, Jokwang and Haedamssal) would be preferable for a triple cropping because of the short growth period of rice.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.4
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• pp.511-516
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• 2007

This experiment was conducted to evaluate the effects of differently maturing corn hybrids on silage production and milk production per unit area in the northern part of Japan, where grain development occurs under decreasing ambient temperature. Both hybrids were harvested at the same time. The stages of maturity for the early-maturing hybrids (EH; 80 d relative maturity) and the mid-maturing hybrids (MH; 93 d relative day) were early dent and late dough stage, respectively. The plant yields for MH were higher than those for EH. The dry matter (DM) content of MH was lower than that for EH, and the effluent loss for MH silage was greater than that for EH silage. Therefore, the DM yields of prepared silage per area were similar for both treatments. Twelve multiparous mid-lactation Holstein cows ($58{\pm}13$ days in milk) were fed diets based on EH or MH silage in a crossover design with two 3-week periods. Cows were fed 3 kg of hay crop silage (DM basis) and either EH or MH silage ad libitum, and concentrates were supplied to meet NRC requirement for dairy cows. Silage DM intake for EH was found to be higher (p<0.05) than that for MH (10.0 vs. 9.1 kg/day). Milk production and milk composition for EH were similar to those for MH. Feed efficiency per total feed intake was similar in both treatments, although the feed efficiency per concentrate intake tended to be higher for the EH than that for the MH diet. These results indicate that differences in maturation in corn hybrids affect the effluent production of silage and the silage intake of dairy cows. It may be advantageous to plant early hybrid corn with a reduction in effluent production of silage as well as a reduction in purchased feed costs for dairy cows under the climatic conditions of the northern part of Japan.

• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.3
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• pp.215-222
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• 1994

This experiment was conducted to find out the response of orchardgrass (Dactylis glorneruta L.) varieties to grazing at the condition of monocultures and mixed pastures on the field of Livestock Experiment Station at Suwon from Sep. 1989 to Oct. 1991. The varieties of orchardgrass used in this experiment were Potomac, Hallmark and Syn. No. 2 as a early maturing type, and Lidacta, Rancho and Syn. No. 10 as a late maturing type. The results obtained were as follows: 1. Herbage utilization of mixture with Hallmark variety(T2) was the highest as 78.2% and that with Rancho variety(T5) was the lowest as 70.2%. but there was no difference(P>0.05). Mixtures with early maturing varieties(T1, T2 and T3) were higher as 77.4% than those with late varieties(T4, T5 and T6) as 72.9% in herbage utilization. In monocultures Rancho variety(T5) was the highest as 68.6% and Lidacta variety(T4) was the lowest as 58.8%, and mixtures with early maturing varieties(T1, T2 and T3) as 66.6% were higher than those of late(T1, 72 and 73) as 64.6%. 2. The content of crude protein of 6 mixed pastures ranged from 19.7% to 22.8%, and those of ether extracts, crude fiber, crude ash and nitrogen free extract were 6.6 to 7.5%, 24.9 to 26.2'76, 1 1.5 to 1 1.9% and 33.6-35.4 8, respectively, But there were not different significantly(P>0.05). In monocultures, significant difference by variety was observed in crude protein content(P<0.05). 3. In botanical composition, there was just a little different among 6 mixtures, having 90% or more in grass percentage. The percentages of each orchardgrass varieties were decreased, but those of perennial ryegrasses were increased as grazing sesson was progressed in all treatment.

• Journal of Korean Society of Forest Science
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• v.31 no.1
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• pp.48-52
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• 1976

In order to investigate the effects of seed weight, size (length and thickness), and maturation period (early maturing seed or late maturing seed) on growth of first-year seedlings in Pinus koraiensis, pot cultivation experiment with seeds collected from Gangweon University Forest was carried out under relatively controlled environment condition. At the end of one growing season, not only fresh weight, length, diameter (at underside of cotyledon) and root length of seedlings, but also number and length of cotyledon were measured. Results are as follows; 1. Germination percentage is independent of weight and size of seeds, but it was influenced by maturation period, that is, late maturing seeds surpass early maturing one in germination percentage. 2. Germination percentage is affected by maturation period of seeds in 18.3% of contribution rate. 3. Each growth of first-year seedlings is influenced considerably by the differences of weight, length and thickness of seeds, that is, heavy and large seeds produce larger seedlings than do light and small seeds. Particularly, fresh weight, diameter, length of cotyledon are significantly affected by differences of seed weight and size (length and thickness) in 50-90% of contribution rate. 4. Differences of seed weight and thickness have a tendency to affect more on growth of first-year seedlings than do differences of seed length. 5. Seedlings from late maturing seeds are superior than those from early maturing one in fresh weight, diameter of seedlings and length of cotyledon, but it's influence is a little.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.199-206
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• 2004

Typhoon "MAEMI", happened in September 2003, hit the great damage to Gyeongnam province area. Especially, rice plant was lodged or severe leaf damage was caused. This study was conducted to find out the extents of leaf damage among different rice cultivars, and to evaluate rice yield and eating quality due to leaf damage after typhoon. Rice cultivars torn off over half of the flag leaf length (FLL) were one medium-late maturing cultivar (Donginl), medium maturing cultivar (Yeonganbyeo), eight early maturing cultivars (Samcheonbyeo, Jounghwnbyeo, Munjangbyeo, Taebongbyeo, Odaebyeo, Samhaegbyeo, Sobaegbyeo, Sinunbongbyeo), two long-il type cultivars (Samgangbyeo, Namcheonbyeo), and three special use cultivars (Heukseonchalbyeo, Jinbuchalbyeo, Yangjobyeo). Cultivars torn off below 1/10 FLL were eight medium-late maturing cultivars (Chucheongbyeo, Daecheongbyeo, Saechu cheongbyeo, Donganbyeo, Daeyabyeo, Hwamyeongbyeo, 방eongsanbyeo, Dongjinbyeo) and two medium maturing cultivays (Donghaebyeo, Gumobyeo2). The rest cultivars were tore off by 1/10∼1/2 ELL. In yield components, the longer was flag leaf damage, the lower was ripened grain ratio, grain weight and brown/rough rice ratio, which was severly impacted to late than to ordinary season cultivation. However, rice yield did not decrease up to tearing by 1/10 ELL. Head rice ratio decreased from flag leaf tearing over 1/10 ELL in late season cultivation. The longer was flag leaf damage, the lower was eating quality, which could not show significantly different.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.243-250
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• 2011

This experiment was conducted to evaluate agronomic characteristics, forage quality and dry matter (DM) yield of early-maturing hairy vetch 'Cold green', 'Haymaker plus', 'Cappello' and medium-late maturing cultivar 'Cheong pa', 'Challenger', 'Hungvillosa' and 'Latigo' at Seongju in the Kyeongbuk from 2009 to 2011. The experiment was arranged in randomized complete block design with three replications. Hairy vetchs were seeded on Sep. 26 and Oct. 11 in 2009 and 2010. Vetch plants were harvested on 30 Apr. in 2010 and 2011. Cold tolerance for Haymaker plus and Cappello were a little lower than other cultivars. Fifty percent-flowering dates of Cold green had earlier than others and Haymaker plus and Cappello were earlier than Cheong pa, Challenger, Hungvillosa and Latigo. Cheong pa and Challenger were ealirer than Hungvillosa and Latigo. The DM yield of Cold green was the highest (p<0.05) of the cultivar except Haymaker plus. Haymaker plus was higher (p<0.05) than others and Cappello, Cheong pa, Challenger were higher (p<0.05) than Hungvillosa and Latigo in 2010. In 2011, the DM yield of Cold green was the highest (p<0.05) of the cultivar and Haymaker plus was higher (p<0.05) than others. Cappello was higher (p<0.05) than Hungvillosa and Latigo. Cheong pa and Challenger were higher (p<0.05) than Latigo. Vetch cultivar was high in crude protein (CP) and low in Acid detergent fiber (ADF). According to the results obtained from this study, it is suggested that early-maturing cultivar would be recommendable for fall sown vetch for DM production.

• Horticultural Science & Technology
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• v.17 no.1
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• pp.21-22
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• 1999

'Choha' was released by the National Horticultural Research Institute in 1997 as a new early-maturing and high-quality apricot variety, which originated from the crossing of 'N.Y. 472' and 'Early Orange' in 1986. This variety was tested as 'Wonkyo Sa-05' at 4 areas for 3 years from 1995. 'Choha' is resistant to fruit cracking by rainy spells just before fruit maturing. Fruits mature in late June, earlier than any other varieties. The content of soluble solids is $12.5^oBx$ and fruit acidity is low. Fruits are relatively large, about 60g in weight.

• Journal of The Korean Society of Grassland and Forage Science
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• v.11 no.2
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• pp.137-142
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• 1991

For the constitution of forage cropping system including the double-cropping of corn, attention has been directed towards the early and short maturing varieties of corn such as Comet 80, Comet 85 and Linda as a component forage crop of forage cropping system. Four corn varieties, Comet 80, Comet 85, Linda and Suwon 19 were planted delayedly by each of 45, 55 and 65 days from the recommended sowing date of suwon 19. Under these condition, growth characteristics and late-sowing adaptability of 4 corn varieties were investigated, and the results are summarized as follows; 1. The variety of suwon 19 did not reach the stage of silking in the occasion of late sowing by 50 days from the optimum sowing time for mono cropping of suwon 19. However early varieties such as Comet 80, Comet 85 and Linda silked under the condition of 65 days-delayed sowing from the recommended sowing time of Suwon 19 for mono-cropping. 2. Early varieties of Comet 80, Comet 85 and Linda were so grown by approximately 92% in plant height, 66% in ear height, 88% in stem diameter and 81% in leaf number respectively compared to Suwon 19 at each of three delayed sowing time that exhibited the dwarfish appearance of canopy. 3. Days from sowing to silking decreased as the sowing time was delayed and the average days from sowing to silking in the sowing treatments of 55 days-delayed of Suwon 19, Comet 80, Comet 85 and Linda were 61, 46, 47 and 51 days, respectively. 4. The size of variations of plant height and ear height influenced by delayed-sowing time was comparatively larger in the varieties of Suwon 19 and Linda than in those of Comet 80 and Comet 85. 5. As sowing time was delayed from the optimum sowing time of Suwon 19 for mono-cropping, ear content decreased from 0% of Suwon 19 at 55 day-delayed sowing treatment to 3540% of Comet 80 and Comet 85 at 65 days-delayed sowing treatment.

• Korean Journal of Agricultural Science
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• v.42 no.3
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• pp.151-158
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• 2015

This study was conducted to know the variation and relationship of rice grain quality and starch pasting properties by transplanting times. Two early maturing rice cultivars which accounted for the most area of early maturing rice cultivar in Chungnam province were used. The experiment was laid out in a split-plot design with 3 replications. The main plot consisted of three transplanting times viz. early (April 25), ordinary (May 25) and late (June 25) with sub-plots containing two cultivars. According to the transplanting times, most of rice grain quality and starch pasting properties showed significant difference and Joami showed higher grain quality than Unkwang in all transplanting times. Especially, rice grain quality was improved when transplanted late, showing high head rice and glossiness of cooked rice due to the lower mean temperature during grain filling stage. Glossiness of cooked rice was positively correlated with head rice ratio, amylose content and setback value, and negatively correlated with chalky rice ratio and protein content. The highest positive and negative correlation were observed between breakdown value and peak viscosity ($r=0.98^{**}$), and breakdown and setback ($r=-0.94^{**}$), respectively. These results provide some information for rice researchers and producers producing cultivars with an improved quality, suggesting that rice quality is highly influenced by temperature at grain filling stage, and transplanting times is crucial in improving rice quality. In addition, starch pasting properties are useful for determining rice quality because rice grain quality and starch pasting properties are dependent on each other.

• Applied Microscopy
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• v.28 no.4
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• pp.447-463
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• 1998

This study was carried out to investigate the histomorphological changes and the electrophoretic patterns of egg components, obtained from 100 of 2-year-old female catfishes (Silurus asotus). Female Korean catfishes collected in the vicinity of Chollabukdo have synchronous ovaries which discontinously ovulate eggs during the breeding season (from late May until early July). The fishes were killed by severing the spinal cord just posterior to the head after immobilization with tricaine methanesulfonate (MS 222). Especially, the light microscopic and ultrastructural changes of ooplasm and follicular membranes of oocytes, were examined by means of light and transmission electron microscopy. The size of the nucleoli and number of the yolk granules increased as the oocyte groved. Yolk granules were deposited in the oocyte as fluid Due to tile presence of large early and late maturing oocytes, their ovaries were enlarged, transparent, granular and greenish in color. As the percentages of fish in late maturing oocyte (LMO) and ripe oocyte (RO) stage increased from March to April, mean gonadosomatic index (GSI) values (19.95%) increased. Zona radiata changed from squamous into cuboid in shape in the early maturing oocyte (EMO) stage. Processes, microvilli, from the zona radiata and from the oocyte grow, and make contact with each other in the pore canals of the zona radiata during vitellogenesis, but are withdrawn as the zona radials becomes more compact and devoid of pore canals during oocyte maturation. Seasonal changes in the microscopic appearance of the ovaries were well correlated with those in both gonadosomatic index and macroscopic appearance. The main cytological changes such as increase in size of cell, nucleus, nucleolus, and increase in number of nucleoli and mitochondria demonstrated with electron microscopy in the previtellogenic oocytes of Korean catfish, provided evidences for important synthetic processes in an early preparatory phase of oocyte development. The electrophoretic pattern of major band in mature stage was much thicker (24 k, 66 k, 90-110k dalton) than that in previtellogenic phase.