• Journal of The Korean Society of Grassland and Forage Science
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• v.8 no.1
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• pp.14-19
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• 1988

This experiment was conducted to investigate the effects of the different cutting height on the changes of nonstructural carbohydrate contents, winter survival, spring yields of Italian ryegrass, tall fescue and pernennial ryegrass swards. It was carried out on the experimental field of Livestock Experiment Station, in Suweon, from Sept. 1986 to May 1987. The results obtained are summarized as follows: 1. The changes in soil surface temperature of plots were slightly appeared among grasses. But not appeared with cutting heights. 2. Nonstructural carbohydrate contents of three grasses until wintering showed much more in line with unclipped, 15 cm cutting and 6 cm cutting height. Among three grasses, Italian ryegrass was highest and tall fescue was lowest. Otherwise, wintering survival was not show the difference among grasses and cutting heights. 3. The green yields was much more producted in line with Iralian ryegrass, perennial ryegrass and tall fescue. But in dry matter yields, it was not significantly different among grasses and cutting heights.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.3
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• pp.4472-4482
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• 1977

In order to estimate furture consumtive use, some statistical characteristics of 22-year pan evaporation data at four selected stations were calculated in this study. Districal distribution, trend analysis and time-series, statistical and periodic analysis for annual, monethly and ten-day values were performed in the statistical analysis. The stations are Seoul, Taeku, Jeonju and Mokpo for monthly data, and Suweon data are compared to the reported Penman values. The results are as followed: 1. Annual evaporation ranged to 990-1,375mm varying with the locations of the stations. The Districal distribution of evaporation in the Republic is shown in Fig. 1. 2. The trend analysis for annual evaporation resulted in detail in Table 2 and Fig. 2, through simple moving average methods. The results show relatively short-period data of about 10 years would be acceptable for field use. 3. The means and dispersions of monthly evaporation at four stations are detailed in Table 3. 4. The monthly evaporation approached to the trend of normal distribution Fig. 3 showed the examples of normal distribution for each typical monthly data. 5. The correlograms detailed in Fig. 4, shows the time-series characteristics of monthly evaporation, whose periodic term should be twelve months. 6. The periodic analysis for monthly evapolation results in Table 4. Fig. 5 shows the comparison of estimated values to actual and the trend approaches Shuster's periodic trend. 7. A periodic description of days after March 1 for irrigation periods was developed to predict ten-day evaporation in Fig. 6. The ten-day etraporation is different in the distribution form and occurence period of maximum values from the reported Penman's man's evapotranspiration.

• Korean journal of applied entomology
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• v.19 no.4 s.45
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• pp.243-248
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• 1980

Experiments were conducted to study on bionomics and control of cutworms; Agrotis tokionis, A. ipsilon, A. fucosa in Suweon, 1978-1979. A. ipsilon and A. fucosa had two or three generations and A. tokionis had one generation a year. A large number of A. toikonis occured at the end of September, and the major peaks of the first generation of A. tokionis and A. fucosa were in mid-June, the second generation in mid-August, and the third generation was at the end of September. These cutworms laid many eggs on the lower surface of curved downward leaf of Chinese cabbage and the larvae later than 3rd instar began to cut the basal part of stem and then pulled into the soil. A parasite of A. tokionis, a braconid wasp, Meteorus rubens, and two unidentified Ichneumnid wasps were found. Mocap and Volaton gave effective control to the cutworms but Volaton should be applied not to contact with plant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.173-177
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• 1992

This experiment was carried out to determine the effect of harvesting dates on the dry matter yield and quality of "Kool grazer" winter rye(Seca1e cereale L.) as a soilage crop at the Forage Experimental Field of College of Agrlc. and Life Sciences, SNU, Suweon. Four-day harvasting interval was allocated to measure the growth, yield and quality of rye from April 14 to May 18, 1987. Rye was rapidly grown as 3 cm/day and the growth was linearly recorded from the elongation to flowering stage. The dry matter and in vitro digestible dry matter(1VDDM) yields per ha were linearly increased up to 0.26 and 0.19 tonlday from April 14 to May 4 and April 14 to 29, respectively, but major breaks in yield increases occurred at the 50% heading stage, than yields increased. The highest crude protein yield was observed at the first heading stage of April 29, then decreased. Acid detergent fiber (ADF) and crude protein(CP) contents of rye at the heading stage of May 5 were 35 and 17%, respectively and the nutritive value of rye in terms of ADF and CP contents was evaluated as the I st grade hay, but neutral detergent fiber(NDF) content of rye was 47 % at the boot stage ofApril 22 and evaluated as the 2nd grade hay in terms of NDF content. The results indicate that the first heading stage or the end of April would be the most suitable harvesting time for early maturing winter rye as a soilage crop in terms of yield and quality in the middle northwestern coast rcgion of Korea. of Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.229-235
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• 1985

Zoning of the agroclimatic regions was attempted based on the distribution of drought index, effective temperature, meteorological factors and their standard deviation and a climatic productivity derived from yield response of rice to temperature and sunshine hours. The meteorological data obtained from synoptic weather stations under the Central Meteorology Office and simple weather observatories under the Rural Development Administration at 155 locations throughout the country were computerized in the PDP11/70, RDA Computer Center, to analyze the climatic similarities among the locations, except the Jeju Island. The nineteen different agroclimatic regions were classified, ego the Taebaeg Mountainous Region. the Charyung Southern Plain Region, etc., and the climatic characteristics of the regions were identified.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.85-88
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• 1979

The cotton aphid, Aphis gossypii Glover, is known as the most important vectant vector of citrus tristeza virus, cucumber mosaic virus, potato virus Y and potato leafroll virus. This study conducted to investigate the life history of cotton aphid at Suweon, Korea$(Lat.37^{\circ}16'N,\;Long\;126^{\circ}59'E)$. The aphids were reared in small cages placed over twig of hibiscus and on the leaves of cucumber. The results obtained were summarized as follows: 1. Overwintering eggs hatched from mid to late April, with a hatching rate averaging seventy-nine percent. 2. The early-born progeny have 22 generations and the late-born progeny have 6 generations on hibiscus and cucumber from April to October. 3. The fundatrigeniae leave tile the primary host in late May to early June and migrate to the secondary hosts. 4. From early to mid Oct., the gynoparae migrate from the secondary hosts to the primary host. 5. The average length of life was about 29 days and they produced an average of 70 nymphs each. 6. The maximum number of aphids produced per female was 117 in the spring. 7. The developmental period ranged from 6 to 16 days (average 8 days), the reproductive period from 12.2 to 24.6 days (average 19 days). 8. The average number of nymphs produced by a female per dys was about 3.7, with a maximum number of 17.

• Journal of Animal Environmental Science
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• v.6 no.1
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• pp.53-58
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• 2000

A manure management plan is important for all daily operations. This study was conducted to investigate the effect of application level of liquid cattle manure on the soil properties and changes of BOD and COD content in run-off water at the mixtures swards of National Livestock Research Institute RDA Suweon in 1995. The experiment was arranged in a randomized block design with five treatments consisting of no fertilizer chemical fertilizer application of 40, 60 and 80MT/ha as liquid cattle manure. The quantity of run-off for a no fertilizer was the highest of 1,469.4mm but that for a application level of liquid cattle manure of 60MT/ha was the lowest of 1,278.1mm. The change of BOD in run-off for a no fertilizer was the lowest of $19.84m{\ell}/{\;}{\ell}$, but that for a application level of liquid cattle manure of 80MT/ha was the highest of $36.22m{\ell}/{\;}{\ell}$. Change of COD in run-off for a no fertilizer was the lowest of $21.28m{\ell}/{\;}{\ell}$ but that for a application level of liquid cattle manure of 80MT/ha was the highest of $37.51m{\ell}/{\;}{\ell}$. Available phosphorus and total-N content of soil chemical properties was higher at liquid cattle manure than chemical fertilizer.

• Journal of Korean Society of Forest Science
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• v.64 no.1
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• pp.1-10
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• 1984

Two fast-growing clones 65-29-19 and 66-6-8 and two less fast-growing clones 66-14-29 and 66-14-99 were compared at intensively cultured plots to identify what morphological characters are related to fast growth and high biomass yield of Populus alba ${\times}$ Populus glandulosa $F_1$. The plantations were established in the spring of 1982 and 1983 at the Seoul National University nursery in Suweon. Differences in dry matter production were found among two-year-old clones but not, among one-year-old clones. Highly significant correlations were found between total leaf area per tree and total dry weight per tree and between total branch length per tree and total dry weight per tree for two-year-old clones. This relation was more obvious during the late growing season. Morphological characters desirable for producing high biomass identified in fast-growing clones were as follows; high shoot-root ratio, high leaf surface area per tree, long leaf retention period, and many small leaves and compact crown architecture in the upper portion of true crown.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.121-126
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• 1999

Manure management is a top priority on both dairy and swine farrns at present. This experiment was carried out to determine the effect of different types and N rates of liquid manure on forage yield and quality of oats(Avena sativa L.) in Suweon, 1997. Seven treatments consisting of chemical fertilizer $120kg\;N\;ha^{-1}$, liquid cattle manure 120, 240 and $360kg\;N\;ha^{-1}$, and liquid swine manure 120, 240 and $360kg\;N\;ha^{-1}$ were arranged in a randomized complete block design with three replications. As increasing N rate of the liquid manure, the plant height was increased, but dry matter content of oats was decreased as increasing liquid manure N rate. There were significant differences in dry matter yield of oats among the liquid manure N rates(P<0.05). Crude protein(CP) content of oats ranged from 14.7 to 24.1% (P<0.05), and CP yield was orderly ranked as liquid swine manure $360kg\;N\;ha^{-1}$>liquid cattle manure $360kg\;N\;ha^{-1}$>liquid swine manure $240kg\;N\;ha^{-1}$(P<0.05). Acid detergent fiber(ADF) content of the liquid cattle manure treatment showed a slightly higher than that of the liquid swine manure treatment(P<0.05). Neutral detergent fiber(NDF) content of the liquid cattle manure treatment was lower than that of the liquid swine manure treatment(P<0.05). Relative feed value(RFV) of the liquid cattle manure treatment decreased with increasing liquid manure N rates compared with that of the liquid swine manure treatment. Based on the results of this experiment, it is indicates that to increase the N rates from liquid manure application could be obtained from the increase of forage yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.373-378
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• 1999

This study was conducted to investigate the effects of application of the dolomite particles and the shell powder on soil characteristics, dry matter yield and nutritive value of forage in sandy loam soil at the Experimental Field of National Livestock Research Institute, Suweon, from 1994 to 1996. This was compared with control, lime, dolomite 0.5mm, 2.0mm, 4.0mm, and shell powder in mixed pasture. Although there was no significant difference, average dry matter yield for 3 years was increased with the application of lime, dolomite 2.0mm, 0.5mm, control, 4.0mm and shell powder in order. Average crude protein yield of forages was increased with the application of dolomite 2.0mm, 0.5mm, control, lime, shell powder and 4.0mm in order. Lime requirement was slightly increased from 2,410 to 4,853kg per ha with the lapse of time. Although soil hardness was optimum level by second year, it was apt to become hard little by little. Solid phase of soil was lowered with dolomite 0.5mm treatment. The results demonstrated that dolomite and shell powder could be settled a dust problem in farms and a coast pollution as lime substitutes for soil improvement. Therefore, it is desirable for dry matter yield and crude protein yield to applicate the dolomite 2.0mm every 3 years and the shell powder more frequently in sandy loam soil.