• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.256-266
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• 2022

Empirical models including the Angstrom-Prescott (AP) model have been used to estimate solar radiation at sites, which would support a wide use of crop models. The objective of this study was to estimate two sets of solar radiation estimates using the AP coefficients derived for climate zone (AP_Frere) and specific site (AP_Choi), respectively. The daily solar radiation was estimated at 18 sites in Korea where long-term measurements of solar radiation were available. In the present study, daily solar radiation and sunshine duration were collected for the period from 2012 to 2021. Daily weather data including maximum and minimum temperatures and rainfall were also obtained to prepare input data to a process-based crop model, CERES-Rice model included in Decision Support System for Agrotechnology Transfer (DSSAT). It was found that the daily estimates of solar radiation using the climate zone specific coefficient, SFrere, had significantly less error than those using site-specific coefficients S_Choi (p<0.05). The cumulative values of S_Frere for the period from march to September also had less error at 55% of study sites than those of S_Choi. Still, the use of S_Frere and S_Choi as inputs to the CERES-Rice model resulted in slight differences between the outcomes of crop growth simulations, which had no significant difference between these outputs. These results suggested that the AP coefficients for the temperate climate zone would be preferable for the estimation of solar radiation. This merits further evaluation studies to compare the AP model with other sophisticated approaches such as models based on satellite data.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.238-246
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• 1994

Rate of conventional allpication of chemical fertilizer and farm manure were surveyed for 23 crops and 13,259 farms on paddy and upland fields in 1992. 1. Farmers have applied fertilizers more than optimum levels on vagetable crops. Based on the optimum levels of N, P and K, the excess ratios of N, P, K fertilization were 40%, 138%, and 53% in vagetable crops and 38%, 7%, and 0% in field crops, respectively. 2. Among provinces, the fertilizer application for paddy rice was higher in Chung-nam and Jeon-buk, which have had higher yield compared to other provinces. And that for red pepper was higher in Kang-won, Jeon-nam, Jeon-buk, Kyeong-nam, Kyeong-buk, and for chinese cabbage in Kang-won and Chung-nam. 3. The fertilizers rates at a chief producing districts of crops(CPD) were higher in vagetable crops than in field crops. 4. Compared with total fertilizer levels of open culture, excess fertilizers in plastic house were 5.9kg/10a(21%) of nitrogen, 8.7kg/10a(52%) of phosphorus and 7.1kg/10a(34%) of potasium. In chemical fertilizer application, fertilizer levels of sweet corn, red papper, tomato and lettuce were higher in plastic house, while those of cucumber, strawberry, radish, chinese cabbage were higher in open culture. 5. Ratio of farmers who applied farm manures was below 60 % on field crops and 69~100% on vagetable crops. 6. The compound fertilizer for paddy rice(21-17-17) was applied on all the crops and its application rate was the highest in all the crops except for paddy rice(single cropping), malting barley, soybean, sesame.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.783-800
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• 2007

The current study was conducted to investigate the effect of high quality hay on the performance and carcass characteristics of Hanwoo steers. Twenty(20) Hanwoo(7 months old) were allocated into either Control(rice straw fed) or Treatment(timothy hay and rice straw fed) group(10 animals per group) and fed for 710 days until the animals reached at 30 months old. Concentrates were fed according to the feeding program composed with three(3) phases; growing, fattening, and finishing period. For the overall feeding period, final body weights were 761.3 and 799.6kg for the Control and Treatment groups, respectively, showing 38.3kg heavier body weight in Treatment group. ADG were 0.79 and 0.84kg for Control Treatment groups, respectively. These results might be because of the intake of high quality hay during growing phase and the effects persisted until the end of the experiment. Feed intake tended to be higher in Treatment group whereas feed conversion did not show significant difference between groups. Cold carcass weights were 451.0 and 475.3kg for Control and Treatment, There were no significant difference between groups in both yield and quality grade. There were no remarkable differences in physico-chemical characteristics fatty acid composition of carcasses between groups. In conclusion, it would be beneficial to feed high quality hay such as timothy during growing period of Hanwoo steers to produce high quality beef with heavier live and carcass weight.

• The Korean Journal of Mycology
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• v.16 no.4
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• pp.220-225
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• 1988

This study was carried out to investigate the effect on the system of crop rotation of sesame(Sesamum indicum L). The results of infected plant percentage and yield of sesame wilting disease, fluctuation of density of Fusarium oxysporum and Actinomycetes, and their pathogenicity test on Fusarium spp isolated from sesame cultural soil were investigated. Density of F. oxysporum was the highest in a sesame continuous cropping soil but that of Actinomycetes was the lowest in that soil. And that of F. oxysporum and Actinomycetes according to investigation date was the highest at June. 30 and July. 30, respectively. Their pathogenicity of F. oxysporum and F. solani isolated from sesame cultural soil to sesame, peanut and green gram were recognized to all isolates except one isolate among F. oxysporum 8 isolates and one isolate to sesame, 2 isolates to peanut and all isolates to green gram among F. solani 4 isolates. F. oxysporum density and infected plant of wilting disease were increased as a result of replanted cultivation of sesame, and yield of that was prominantly reduced. Relation between density of F. oxysporum in cultural soil and infected plant percentage showed positive correlation and yield index highly negative. There was little difference between sesame-upland rice and sesame-peanut in the system of crop rotation.

• Journal of Animal Science and Technology
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• v.55 no.1
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• pp.33-39
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• 2013

This study was conducted to investigate the effects of feeding patterns of concentrates on growth performance, blood parameters and carcass characteristics in Hanwoo cows. Randomly-allocated groups, restricted concentrate feeding (T1), restricted concentrate feeding for 6 months and ad libitum 2 months (T2), restricted concentrate feeding for 4 months and ad libitum 4 months (T3), were contained with 9 animals. According to feeding patterns of concentrate, growth performance was not significantly different among the treatment groups. However, ADG tended to be higher in T2 group (0.75 kg/d) compared to the other groups (T1: 0.62 kg/d, T3: 0.72 kg/d). DMI was not significantly different among the treatment groups, interestingly, rice straw intake was significantly higher in T1 group compared with others (p<0.05). There were significant difference among feed conversion ratio, which are 17.8, 12.8, and 14.1 kg for T1, T2, and T3 (p<0.05), respectively. The serum level of albumin, triglyceride, glucose and GPT were greater in T3 group compared to other groups at fattening 6 to 8 months (p<0.05). The results of yield traits, carcass weight, back fat thickness and rib eye area were not differ among treatment groups, but yield index was significantly greater in T2 group compared to T1 group (p<0.05). The 'A' appearance rate (%) of meat yield grade was highest in T2 group for 78%. The marbling score, meat color, fat color, texture and maturity in quality traits were not differ among the treatment groups. However, marbling score and appearance rate (%) of over 1st meat quality grade were tend to be increased at T3 rather (4.0, 56%) group compared with other groups (T1: 3.4, 56%; T2: 3.6, 33%). Thus, the present study suggested that restricted concentrate feeding (1.6% of BW) for 4 months during early fattening periods and ad libitum feeding for 4 months during late fattening periods are recommendable.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.4
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• pp.307-312
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• 2009

This experiment was conducted to compare the agronomic characteristics and productivity of induced annual legumes at paddy field of Cheonan and Naju from 2004 to 2006. Chinese milk vetch (wild type), crimson clover (C.V. Linkarus), forage pea (C.V. Austrian pea), hairy vetch (C.V. Oregon commen) were used in this study. At the Naju region, the earliest flowering on 2nd may was found in Chinese milk vetch, while the latest on 18th May in forage pea. Fresh, dry matter (DM) and crude protein (CP) yields of crimson clover were highest as 28,870, 6,986 and 943 kg/ha, respectively. but the yield of chinese milk vetch was low by 9,885, 1,749 and 338 kg/ha. At the Cheonan region, the most fast flowering date variety was Chinese milk vetch, hairy vetch was very late as 19th May. Fresh, DM and CP yields of hairy vetch were highest as 7,916, 1,141 and 113 kg/ha, respectively. but the yield of chinese milk vetch showed the lowest by 270, 42 and 8 kg/ha. The CP content of annual legumes was 14.3%. chinese milk vetch showed the highest CP content by 19.3% and hairy vetch showed the lowest content by 9.9%. The present data showed that the productivity was closely dependent on winter hardness, in conclusion, crimson clover at Naju and hairy vetch at Cheonan region was suggested to be the most proper species as winter crop after rice harvest on paddy field when considered the winter hardiness.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.721-726
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• 2010

'Nampung', a new soybean cultivar for soy-paste, was developed from the cross between Suwon190 and 'Pokwangkong' by soybean breeding team at the National Institute of Crop Science (NICS) in 2007. A promising line, SS97215-S-S-20, was selected and designated as the name of Milyang162. It was prominent and had good result from regional adaptation yield trials(RYT) for three years from 2005 to 2007 and was released as the name of 'Nampung'. It has a determinate growth habit, white flower, brown pubescence, yellow seed coat, light brown hilum, medium spherical seed (19.9 grams per 100 seeds). 'Nampung' is resistant to soybean mosaic virus and bacterial pustule, the major soybean disease in Korea. It is possible to harvest of 'Nampung' using combine because of it's lodging tolerance, few branches, and high position of pod attachment. The average yield of 'Nampung' is 2.97 ton per hectare in the regional yield trials (RYT) carried out for three years from 2005 to 2007 which is 21 percent higher than the check variety, 'Taekwang'.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.684-689
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• 2010

'Sangwon', a new cultivar for vegetable soybean, was developed from the cross between 'Keunolkong' and 'Oshimamidori', and was released at the National Institute of Crop Science (NICS) in 2007. The goal to develop a vegetable soybean cultivar with green pod, early maturity, large seed size, high yield, lodging tolerance, and resistance to disease such as soybean mosaic virus (SMV). 'Sangwon' has light green pod, early maturity, large seed, short plant height, and lodging tolerance. 'Sangwon' has determinate growth habit, white flower, gray pubescence, and oval leaf shape. The matured seeds have a yellow seed coat with light brown hilum, and a yellow cotyledon. 'Sangwon' has 5.8 cm fresh pod length, 13.2mm fresh pod width, 69.5 g seed weight per 100 green seeds, 44.0% green seed protein content, and 14.8% green seed oil content. At the regional yield trials (RYT) for vegetable soybean from 2005 to 2007, 'Sangwon' shows strong resistance to soybean mosaic virus (SMV) and tolerance to lodging in fields. Fresh pods of 'Sangwon' were harvested at the beginning of August. In the same tests, fresh pod of 'Sangwon' (10.39ton/ha) yielded 5% higher than 'Hwaeomputkong' (9.90ton/ha).

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.114-120
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• 1985

This study was conducted to investigate the important weeds occurring in onion and garlic planted in paddy field as the succeeding crop of rice and to evaluate the effect of competition between these crops and weeds on the yield of onion and garlic. In terms of quantity occurred, Persicaria hydropiper, Chenopodium ficifolium, Alopecurus aequalis, Poligonum aviculare, Echinochloa crus-galli, and Bothrisospermum tenellum appeared to be the major weeds in onion and garlic fields. Annual broadleaves were composed of 90.0 and 94.3% of total weed dry weight in onion and in garlic fields, respectively. Among these weeds, P. hydropiper was the most dominant species in onion and C. ficifolium in garlic fields. The higher Simpson's index such as 0.67 in garlic as compared to 0.40 in onion can be attributed to the presence of a C. ficifolium, which is existed in a single dominant species. The full season competition between the crops and these weeds resulted in yield reduction of onion by 23.9% and garlic by 31.9%, showing weed dry weight, 448.18 and 418.40 g/$m^2$ in onion and garlic fields, respectively. The maintenance of weed free condition for about 4 weeks after weed emergence could be the prerequisite to obtain the maximum yield of these two crops.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.4
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• pp.245-251
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• 2013

These experiments are being conducted to obtain data of plant height, panicle length, heading date, number of culm, and fresh and dry weight, crude protein, acid detergent fiber (ADF), neutral detergent fiber (NDF), total digestible nutrients (TDN) by six times seeding of 10 days interval ranging from May 1st to June 21st for two types of barnyard millet from the Suwon area in Korea. In the early-heading type, IT 170609 (Echinochloa crus-galli), the plant height and the number of culm per square meters are decreased by late seeding relatively, and heading date is 7 to 10 days earlier than the late seeding. And the dry weight of forage is rapidly decreased after the June 11th seeding. In the late-heading type, IT 195422 (Echinochloa frumentacea), the plant height and the number of culm per square meters are also decreased by late seeding relatively, and heading date is about 13 days earlier than late seeding. The dry weight of forage was rapidly decreased after the June 11th seeding. In both two types, the nutritive value of ADF, NDF, and TDN are not changed by late seeding, but crude protein is increased by late seeding. The TDN yields of late-heading type, IT 195400, show average amounts in the June 1st seeding, but the TDN yield of early-heading type, IT 170606, indicate safety amounts of dry weight to the March 21st seeding. And these data are available for cropping systems, cultivating barnyard millet in summer and cereals for forage in winter, to get high production of forage in Korea.