• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1277-1284
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• 1999

Eight feeds and their residues left after washing with tap water (water residue) or incubation in the rumen (rumen residues) were treated with hydrochloric acid, neutral detergent solution without EDTA (NDS) or both, and the release or sorption of minerals (Ca, Mg, P, Na, K, Cu and Zn) assessed. Six of the feeds were from Sri Lanka (Panicum maximum ecotype Guinea A, Glyricidia maculate, Artocarpus heterophyllus (jak leaves), untreated and urea-treated rice straw, and rice bran) and two from the Netherlands (maize silage and wheat straw). The initial concentration of mineral elements, the concentration of neutral detergent fibre (NDF) and the type of feed significantly influenced (p<0.01). The proportion of the mineral elements released or sorbed. In general, feeds with high NDF content (straws and guinea grass) sorbed Ca from tap water, or released less in the rumen, and within these feeds the extent of sorption varied with source of fibre. Acid or NDS treatment removed little of the sorbed Ca, but they removed much of the Mg from both water and rumen residues. Fibres of wheat straw and jak leaves showed an affinity for Mg in the rumen. All feeds and their water and rumen residues sorbed P and Na from NDS, and the extent of sorption varied with the initial concentrations of these elements and with the type of fibre. Acid treatment removed part of the sorbed Na, but not the P. The solubility of K was not affected by the content of NDF, the type of fibre or the initial concentration of K. All feeds and their residues, except for the rumen residues of rice bran sorbed Cu from tap water and in the rumen. The recovery of Cu in rumen residues declined from 353% to 147% after NDS treatment, and with some feeds (glyricidia and jak leaves) the recovery was below 100%. Acid treatment removed part of the Zn sorbed by the water and rumen residues, but the capacity of residues to retain Zn varied with the type of feed.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.54-61
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• 2018

Zoysiagrass (Zoysia spp.) exists spotly in Indonesia and it has potential to be used in parks, golf courses, and football fields. Many football fields and golf course fairways use sand as top soil over native soil. This study aims to analyze growth and quality of two native zoysiagrasses Zis and Zim. Zis is a native zoysiagrass collected in sea-side and Zim is a native zoysiagrass collected in mountain area. Both types of zoysiagrasses were planted at field with altitude of 300 m with various growing media mixes of sand and reservoir's sediment. Thickness of the growing medium was 10 cm over an alfisol clay soil. Experimental plots were constructed using factorial completely randomized design with two native zoysiagrasses and 5 types of growing media. Two ecotypes of native zoysiagrasses showed different in growth habits combined with mixtures of growth media. Zim showed higher growing speed including more vigor with uniformity and texture than Zis. There were not significanthly differences on leaf color and root length between two ecotypes of native zoysiagrasses collected in Indonesia.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.3
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• pp.47-54
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• 1978

Weed control is an essential part in rice culture and has been practiced by hand. But the shortage of man power in rural area in recent years has brought about the use of herbicides. The effective use of herbicides in rice has contributed toward improving labor situation and maintaining rice production. The use of herbicides will extend more in the future. The only limitation of present uses of monoherbicides might be the predominant growth of a certain weeds in paddy field, and subsequent effect on ecology system. It is, therefore, wanted to develop a herbicide which will be effective on several kinds of weeds. In the weed control system, ecological and integrated weed control would be necessary in the future. To obtain the most effective weed control, studies on physiological ecotype of weeds and machanism of herbicides and their interactions will be necessary.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.117-123
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• 2000

In order to study the role of polyamines on the formation of adventitious roots, trichomes and calli, the effects of putrescine, spermidine, spermine, cyclohexylamine (CHA) and methylglyoxal-bis(guanylhydrazone) (MGBG) were investigated in the leaf segment cultures from ecotype Columbia of Arabidopsis thaliana. When the leaf segments were cultured on the media for forming adventitious roots (0.1 mg/L NAA), trichomes (2.0 mg/L NAA) and calli (10.0 mg/L NAA), and then each cultures was treated with 1-100 mg/L of putrescine, spermidine and spermine, respectively. On the adventitious root-forming medium treated with polyamines the trichomes were induced with adventitious roots. And on the trichome-forming medium with polyamines calli were induced with trichomes. In orther hand each cultures was treated with 1-100 mg/L of CHA and MGBG, respectively. CHA promoted adventitious roots on the medium for adventitious roots, was not effected on media for trichomes and calli. MGBG inhibited adventitious roots, trichomes and calli in all cultures, and induced adventitious roots on medium for trichomes in high concentration.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.188-195
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• 2005

The dynamics of the fish community in the Lake Hoengseong region, Korea, were investigated from April 2000 to November 2004. During the surveyed period 39 species belonging 10 families were collected, and there were 17 Korean endemic species (43.59%) including Rhodeus pseudosericeus. Dominant species were Acheilognathus lanceolatus (20.10%), Zacco platypus (15.94%), Z. temmincki (6.92%), Carassius cuvieri (6.33%), A. rhombeus (6.18%), Pungtungia herzi (5.13%), and Pseudorasbora parva (4.93), In the comparison community of fish according to ecotype by each studied years, benthic fished are gradually decreasing and pelagic fishes creasing. Also, according to the fish distribution, the fish community of each studied years was divided into 3 groups by UPGMA. Being based on the fish community, similarity analysis results of each artificial lakes and this lake were divided 2 groups by water system, and divided again 3 groups in the same water system. Fish Community of the Lake Hoengseong was similar with that of the Lake Chuncheon and Cheongpyeong of the Bukhan-River.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.211-217
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• 1999

The effect of auxins and cytokinins on the formation of adventitious shoots, adventitious roots, trichomes, and calli in MS basal medium was investigated in leaf segments from ecotype Columbia of Arabidopsis thaliana. Adventitious shoots, adventitious roots, trichome, and calli were formed from leaf segments by a wide range of hormone concentrations and combinations. Adventitious shoots were formed respectively in treatment with 0.1mg/L IAA and 10 mg/L BA. Adventitious roots were formed in treatments with low concentration of IAA and NAA. Trichomes and calli were formed by increasing the concentration of IAA and NAA. The optimal combination was 0.5mg/L NAA and 0.1mg/L BA for trichome formation, 10mg/L NAA and 10mg/L BA for calli formation. When NAA was treated alone in culture media, adventitious roots were formed in 0.1mg/L, trichomes were formed in 2.0mg/L, and calli were formed in 10mg/L. Inductive time for formation of adventitious roots, trichomes and calli were determined at 6,7 and 18 days respectively by periodical transfer of leaf segments from NAA containing medium to NAA free medium.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.121-129
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• 1987

Indonesian varieties were compared with Korean varieties on three different sowing times, each of which had three different nursery periods, at Suwon, Korea (126$^{\circ}$ 19'E and 37$^{\circ}$ 16'S). Indica-type varieties with exception of late-maturing ones had heading regardless of sowing time and nursery period. As the Korean varieties com-pared with those, the earlier sowing plots with shorter period of nursery gave better result in yields and yield components.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.3
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• pp.259-267
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• 2010

This study was performed at Rice and Winter Cereal Crops Department of NICS during 2007 and 2008 to investigate the characteristics of rice leaf emergence and to obtain basic data which can be used for rice growth simulation model by which we can forecast rice growth stage and heading date accurately under different cultivars, transplanting date, and climatic conditions. To confirm leaf emergence rate according to rice maturing ecotype, we surveyed the leaf emergence rate and heading date of Unkwangbyeo, Hwayoungbyeo and Nampyeongbyeo which are early maturing, medium maturing and medium-late maturing cultivars, respectively, according to seedling raising duration and transplanting time. When seedling duration was 15 days, the growth duration between transplanting time and completion of flag leaf emergence on main culm were 51.5~78.3 days in Unkwangbyeo, 55.3~87.9 days in Hwayoungbyeo and 58.4~98.4 days in Nampyeongbyeo, respectively. When seedling duration was 30 days, they were 50.1~75.5 days in Unkwangbyeo, 52.4~84.7 days in Hwayoungbyeo and 56.4~93.8 days in Nampyeongbyeo, respectively. As transplanting time delayed, the emerged leaf number after transplanting decreased in all rice cultivars. The cumulative temperature between transplanting time to completion of flag leaf elongation on main culm were $1,281^{\circ}C{\sim}1,650^{\circ}C$ in Unkwangbyeo, $1,344^{\circ}C{\sim}1,891^{\circ}C$ in Hwayoungbyeo and $1,454^{\circ}C{\sim}2,173^{\circ}C$ in Nampyeongbyeo, respectively. Leaf emergence rate on main culm were precisely represented by equation, y = $y_0$ + a / [1 + exp( - (x - $x_0$) / b)]^c, when we used daily mean temperature as variable.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1091-1095
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• 2009

The aim of this study investigated the fluctuations of 3 characters from 3 ecotypes [early ripening (ER), middle ripening (MR), and late ripening (LR)] of 20 Korean brown rice cultivars in different storage systems [time: 12 and 24 weeks, temperature: low ($10^{\circ}C$) and room ($25^{\circ}C$)]. With increase of storage time and temperature, lipoxygenase activity, and fat acidity increased, whereas germination rate was reduced. ER cultivars exhibited the highest lipoxygenase activity of $35.49{\pm}2.46$ unit/mg protein during 24 weeks storage at $25^{\circ}C$, followed by LR ($32.73{\pm}1.33$) and MR ($32.66{\pm}1.62$) cultivars. The amounts of fat acidity also were observed by the same order (ER: $20.40{\pm}2.12$>LR: $19.68{\pm}1.86$>MR: $19.64{\pm}1.35$ mg KOH/100 g). Germination rate slightly decreased with increase of time and temperature (MR>LR>ER), but MR and LR cultivars showed the most significant changes (ER: $60.90{\pm}23.47%$, MR: $32.66{\pm}13.95%$, and LR: $32.53{\pm}5.87%$). On the basis of above results, MR cultivars were evaluated the highest quality, because high lipoxygenase activity, high fat acidity, and low germination rate have deteriorated in quality and generated off-odor. Thus, MR cultivars might be very important sources in food processing and stored dietary supplement aspects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.61 no.2
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• pp.104-112
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• 2016

A double-cropping system with soybean (Glycine max) following the cultivation of potato, garlic, and onion is widely adopted in the southern region of Korea. For this system, marginal dates for planting must be determined for profitable soybean yields, because the decision to plant soybean as a second crop is occasionally delayed by harvest of the first crop and weather conditions. In order to investigate the effect of planting date on soybean yield, three cultivars (early and late maturity) were planted on seven different dates from May 1 to July 30 in both paddy and upland fields across 2012 and 2013. Soybean yields were significantly different among the planting dates and the cultivars; however, the interaction between cultivar and planting date was not significant. Based on linear regression, the maximum yield of soybean was reached with a June 10 planting date, with a sharp decline in yield for crops planted after this date. The results of this study were consistent with those of a previous one that recommends early and mid-June as the optimum planting period. Regardless of soybean ecotype, a reduction in yield of greater than 20% occurred when soybean was planted after mid-July. Frost during soybean growth can reduce yields, and the late maturity cultivars planted on July 30 were damaged by frost before completing maturation and harvest; however, early maturity cultivars were safely harvested. For sufficient time to develop and reach profitable yields, the planting of soybean before mid-July is recommended.