• 한국작물학회지
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• 제42권3호
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• pp.255-262
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• 1997

벼 군락에서 건물생산량을 태양광의 반사스펙트럼 특성을 이용하여 추정하고자 1993년 4월부터 10월까지 경기도 소재 수원기상대 구내 포장에서 조생종 진부벼와 중만생종 대청벼, 일품벼를 공시 품종으로 하고 생육시기별 태양광 반사스펙트럼과 건물중을 조사한 결과 다음과 같다. 1. 출수전에 근적외광 파장대(720∼l,100nm)의 반사율을 가시광 파장대 (400∼700nm)의 반사율로 나눈 비율이 건물생산량과 상관이 높았으며, 가시광 파장대 중에서도 녹색, 적색파장보다 청색파장(400∼500nm)의 반사율로 나눈 비율이 건물생산량과의 상관이 높았다. 2. 적외광 파장의 반사율을 청색파장의 반사율로 나눈 비율 중에서 특히 R910 /R460 비율이 건물생산량과 가장 높은 정의 상관을 보였다. 3. 출수이전에 R910/R460 비율과 건물생산과의 회귀식을 이용한 추정식 Y=21.24284 X-212.734는 실측치와의 상관관계는 매우 높았다. 4. 출수이후엔 근적외광 파장(720∼l,100nm)의 반사율을 적색파장(600∼700nm)의 반사율로 나눈 비율이 청색이나 녹색파장의 반사율로 나눈 비율보다 건물생산량과의 상관이 더 높았다.

• 농업과학연구
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• 제44권1호
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• pp.67-76
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• 2017

Fermented Rhus verniciflua (FRV) as feed additives act as excellent anti-diarrheal drugs as they increase the intestinal absorption rate therefore being indirectly associated with enhancing growth performance and increasing digestibility in livestock. A total of 80 weaned pigs with an average initial body weight (BW) of $6.82{\pm}1.11kg$ were used to evaluate a diet supplemented with FRV meal in a 6 week feeding trial with two dietary treatments [CON - basal diet; TRT - CON + 0.2% FRV] on growth performance, apparent total tract digestibility (ATTD), blood profiles, fecal microflora, and fecal score. Our results showed that the dietary supplementation of FRV improved (p < 0.05) average daily gain and gain : feed (G : F) ratio during days 15 - 42 and the overall experiment period and also increased the ATTD of dry matter (p < 0.05) at days 14 and 42. On the contrary, there was no effect (p > 0.05) on average daily feed intake, ATTD of nitrogen and energy, and blood profiles during the entire experiment. Moreover, dietary inclusion of FRV significantly increased fecal Lactobacillus (p < 0.05) counts and reduced the diarrhea during days 22 - 42. Thus, the results suggest that FRV can be used as a potential additive to improve growth performance and dry matter and to reduce diarrhea while having beneficial effects on fecal microflora in weanling pigs.

• 한국초지조사료학회지
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• 제43권4호
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• pp.199-205
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• 2023

Pasture formation and management are crucial to avoid yield reduction. This experiment aimed to examine the effects of tall fescue-centered mixed-seeding combinations on yield and vegetation changes in perennial pastures in the central region for two years, from September 2020 to October 2022. The treatments were arranged in three replications in a randomized block design: control (C), tall fescue-based mixture-1 (T-1), and tall fescue-based mixture-2 (T-2). The tall fescue (TF), orchard grass (OG), perennial ryegrass (PRG), Kentucky bluegrass (KBG), and white clover (WC) were used. The emergency rate of grasses (70.0 to 73.3%) did not differ among mixed seeding combinations. Overwintering rates (81.7 to 83.3%) were similar among treatments. The plant height of grasses was similar at each harvest date, with the highest height (86.2 cm) recorded in the second harvest of the first year, followed by that (58.4 cm) in the third harvest of the first year; it was least (38.9 cm) in the fourth harvest of the second year. There was no significant difference in the dry matter yield of grasses among the mixed seeding combination treatments in the first, third, or fourth harvests of the first year (p>0.05). For second-year grasses, dry matter yield was not significantly different in harvest date among the treatments (p>0.05). Based on mixed seeding ratio, orchard grass showed the highest yield at 70% in the C treatment, followed by tall fescue at 80% and 60% in the T-1 and T-2 treatments, respectively, in the first harvest after seeding. There was no significant difference in feed value between treatments (p>0.05), but a significant difference was observed between the third and fourth harvest (p<0.05). Therefore, it indicated that it is important to create perennial pastures in the central region through mixed seeding combinations centered on tall fescue.

• Asian-Australasian Journal of Animal Sciences
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• 제26권6호
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• pp.827-830
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• 2013

To evaluate the effects of feeding four different levels of starter in male Holstein dairy calves, a completely randomized study was conducted, using 28 calves with initial body weight of $40.5{\pm}2.4$ kg. The animals were fed iso-nitrogenous starter and were weaned when they consumed 350, 500, 650 and 800 g/d of starter for 3 d consecutively. Starter and water were available ad-libitum throughout the experiment. Body weight at pre-weaning (less than 5 wk) and post-weaning (8 wk) was lower in calves that received 350 g/d of starter than in the other treatments (p<0.05). Feed conversion ratio (FCR) was the highest among all treatments in pre-weaning period (p<0.05). Dry matter intake (DMI) at weaning and total DMI was higher in that calves received 800 g/d of starter compared with other treatments (p<0.05). Calves fed 350 and 500 g/d of starter were weaned earlier (p<0.05) and showed lower milk consumption (kg, DM) compared with other treatments whereas no significant difference was observed between calves fed 350 and 500 g/d of starter (p>0.05). Dry matter, organic matter and crude protein digestibilities were lower in calves that received 350 g/d of starter compared with other treatments (p<0.05). No differences were observed in acid detergent and neutral detergent fiber digestibility among all treatments (p>0.05).Treatments had no significant effect on time of starting rumination, respiratory score, and days of drug administration for pneumonia. There were no meaningful differences in feces, fecal odor scores, body temperature, and days of drug administration for diarrhea among all treatments (p>0.05). Total dry matter intake at the end of experiment showed no significant difference among calves fed 600 and 800 g/d of starter, but calves fed 350 and 500 g/d of starter showed more dry matter (DM) intake than calves in the 600 and 800 g/d groups (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제30권7호
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• pp.967-972
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• 2017

Objective: Two experiments were conducted to determine the effects of forage-to-concentrate (F:C) ratio on the nutrient digestibility and enteric methane ($CH_4$) emission in growing goats and Sika deer. Methods: Three male growing goats (body weight $[BW]=19.0{\pm}0.7kg$) and three male growing deer ($BW=19.3{\pm}1.2kg$) were respectively allotted to a $3{\times}3$ Latin square design with an adaptation period of 7 d and a data collection period of 3 d. Respiration-metabolism chambers were used for measuring the enteric $CH_4$ emission. Treatments of low (25:75), moderate (50:50), and high (73:27) F:C ratios were given to both goats and Sika deer. Results: Dry matter (DM) and organic matter (OM) digestibility decreased linearly with increasing F:C ratio in both goats and Sika deer. In both goats and Sika deer, the $CH_4$ emissions expressed as g/d, g/kg $BW^{0.75}$, % of gross energy intake, g/kg DM intake (DMI), and g/kg OM intake (OMI) decreased linearly as the F:C ratio increased, however, the $CH_4$ emissions expressed as g/kg digested DMI and OMI were not affected by the F:C ratio. Eight equations were derived for predicting the enteric $CH_4$ emission from goats and Sika deer. For goat, equation 1 was found to be of the highest accuracy: $CH_4(g/d)=3.36+4.71{\times}DMI(kg/d)-0.0036{\times}neutral$ detergent fiber concentrate (NDFC,g/kg)+$0.01563{\times}dry$ matter digestibility (DMD,g/kg)-$0.0108{\times}neutral$ detergent fiber digestibility (NDFD, g/kg). For Sika deer, equation 5 was found to be of the highest accuracy: $CH_4(g/d)=66.3+27.7{\times}DMI(kg/d)-5.91{\times}NDFC(g/kg)-7.11{\times}DMD(g/kg)+0.0809{\times}NDFD(g/kg)$. Conclusion: Digested nutrient intake could be considered when determining the $CH_4$ generation factor in goats and Sika deer. Finally, the enteric $CH_4$ prediction model for goats and Sika deer were estimated.

• 한국작물학회지
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• 제25권4호
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• pp.1-9
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• 1980

To determine the optimum harvest time of recent rice varieties from Indica/Japonica remote crosses, leading varieties Suweon 264 and Milyang 23 were tested for the changes in dry matter weight and moisture content of grain, shattering, shelling ratio, milling ratio, and apparant physical quality during grain development at 5 day-intervals from 20 days to 55 days after heading. The results are summarized as follows: 1. Grain weight (dry matter) reached its maximum (physiological maturity) at 30 days after flowering (DAF) in Suweon 264, and at 35 days in Milyang 23, and thereafter it did not change significantly until 55 DAF. 2. Time course of decrease in grain moisture content (Y, %) during maturation (X, DAF) consisted of two linear phases, i.e. a fast and a slow period: Y=68.245-1.33X until 34DAF, and Y=23.025-0.470X until 55DAF after 34DAF in Suweon 264; Y=73.62-1.634X until 24.5DAF, and Y=33.59-0.570X until 55DAF after 24.5DAF in Milyang 23. Two varieties showed the same grain moisture content of 28% (wet basis) at physiological maturity in spite of the distinct differences in the heading date, time of physiological maturity and thereby ripening climate. 3. Force to shatter a grain ranged about 90 to 100g in Milyang 23, and about 200 to 250g in Suweon 264 and in a Japonica variety, Jinheung. The force, however, did not change significantly with harvest time from 35DAF to 50DAF. 4. The changes in the ratios of shelling, milling, broken rice and tinted rice with harvest time were insignificant during a period from 35DAF to 55DAF. However, ratios of green rice and white belly rice decreased significantly with delay in harvest time during 10 days after physiological maturity. 5. The best time of harvest for maximum yield and good quality is thought to be 10 days after physiological maturity, and grain moisture content at this time was about 20% on wet basis.

• 한국작물학회지
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• 제43권1호
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• pp.38-43
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• 1998

This study examined root growth and distribution under the direct seeding of rice cultivars developed in Korea, Japan, and the U.S. Cultivars from the U.S., especially 'M202' and 'Caloro', had a high ratio of the dry matter partitioning for root and top plant components. Caloro had high root and top growth. 'Koshihikari' from Japan showed the lowest ratio of R/T (root/total dry matter) due to the small amount of root and top plant growth. Most Japanese cultivars except transplanted 'Hatsuboshi' showed low ratio of R/T. Patterns of root distribution for each soil block were recorded by the root box-pin board method. Roots of all cultivars were distributed in blocks A, C, and E in the middle of box, i.e., just below the plant base. Roots of 'Dongjin', M202, and Caloro were distributed deeper than the others. Roots of transplanted Hatsuboshi developed much better than direct seeded Hatsuboshi. Total root weight density was highest in Caloro followed by Dongjin, 'Gancheok', 'Calrose', and the others. The root density of Caloro was twice as much as those of the others except Dongjin. According to cumulative percentages of root distribution on each soil layer, roots of most cultivars were distributed below 20cm. The U.S. cultivars showed vertically well developed root systems as compared to others. A large amount of roots were distributed in the top 15cm of soil layer for Hatsuboshi and Koshinikari, and their root systems appeared to be shallow. In contrast, the rates of root distribution in the top 10cm of soil layer were low for Dongjin, Calrose, and Caloro. These cultivars had relatively deep root systems.

• The Korean Journal of Ecology
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• 제9권3호
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• pp.161-184
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• 1986

An experiment was made in order to analyze the growth characteristics and productivity of Zoysia japonica under control, mowing and TIBA treatment conditions at the experimental farm of Kyung Hee univ. from May 26 to Oct. 1 in 1985. The field was planned by the randomized block design method and each treatment was given to three plots (2${\times}$2, 4${\times}$4 and 10${\times}$10 cm) and was replicated three times. Each plot was 1$m^2$ for Zoysia japonica. The sampling of each plot was taken once a week after sowing. In order to know the dry matter of total standing crops, kept 9$0^{\circ}C$ and weighted each organ of the plants. Total leaf area of a plant was measured by drawing method. The author adopted the growth analysis of English School. The increasing rates of numbers of leaf and stem were remarkably high in each plot between 10th and 12th weak after sowing and it was highest in TIBA treated plot. The increasin rate of leaf area in each plot was remarkably high beween 10th and 12th week and the maximum value of leaf area was 274.00c$m^2$ in TIBA treated plot of 100 plants/$m^2$. The increasing rate of standing crop was remarkably high between 10th and 12th week and the high increasing tendency in TIBA plot resulted from TIBA. The positive correlationship was founded between standing crop and leaf area. The evaporation rather than temperature acted as a main factor of negative correlation with standing crop during the experiment period. Solar radiation had a high positive correlation in the lower density of plot. C/F ratio was low, during the growth period, from 10th to 12th week after sowing and was low in the higher density under each treated plot. T/R ratio was not constant during the sampling period but was high in the lower density. The increasing rates of RGR and NAR were high between 11th and 12th week after sowing. Leaf area ratio was high in higher density in each plot and not constant in all treated plot.

• 한국약용작물학회지
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• 제13권6호
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• pp.241-244
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• 2005

금산 및 음성지역의 4년생 인삼재배 농가포장에서 직파재배 5개소와 이식재배 5개소를 임의로 선정하여 직파와 이식재배에 따른 생육특성 및 엑스와 조사포닌 함량을 비교한 결과는 다음과 같다. 직파재배는 4년근 생존율이 평균 48%로 이식재배의 86%보다 떨어지나 입모수가 평균 96주/3.3$m^2$순로 이식재배의 57주보다 많고 엽면적지수가 커 수량성이 높은 반면, 주당근중은 작았다. 직파재배는 이식재배에 비해 동체의 신장이 양호하나 지근의 발달이 불량하여 동체중의 비율이 높고 지근중의 비율이 낮았으며, 직파재배는 적변 발생율이 적으나 동체와 지근부위의 엑스와 조사포닌 함량이 낮았다.

• 한국초지조사료학회지
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• 제19권4호
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• pp.309-316
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• 1999

풋베기용 콩의 개량을 목적으로 진품 I, II호, 검정 I, II호, 황금, 석량붓콩, 장엽, 검정올콩, 보광, 만리 등 10개의 대두 품종을 재배하여 품종별 특성과 생산수량을 호숙기를 기준으로 비교하였다. 10개 품종 중 초고가 큰 품정은 검정 I(118cm), 검정 II호(114cm)와 진품 I호(114cm)와 진품 I호(114cm)이었다. 또한 생초수량은 진품 I, II호, 검정콩 II호가 각각 ha당 23,841kg, 23,499kg, 22,815kg, 건물수량은 각각 ha당 5,531kg, 5,173kg, 5,236kg으로 다른 품종에 비해 많았다. 호숙기의 대두 식물체의 잎과 줄기의 구성비율은 검정올콩과 보광을 제외하고, 모든 품종에서 잎이 많았으며 엽경비율이 가장 큰 품종은 만리(2.1), 진품 I호(1.9), 황금(1.9)였다. 대두 식물체의 건물율은 호숙기에서 조생종인 석량붓콩과 검정올콩을 제외하면 22~23.4% 사이에 있었다. 이상의 결과를 종합할 때 키가 크고, 수량이 많으며, 잎이 풋베기용으로 적합한 품종은 진품 I, 검정 II이었다.