제주도 혼파목초지 식생의 연차적 변화에 관한 연구

趙南棋 韓國作物學會 1979 Korean journal of crop science Vol.24 No.4

본 연구는 제주도 개량목초지에서 1971~1978 연까지의 식생의 연차적민 변화과정을 조사한 결과로서 그 개요는 다음과 같다. 1. 식생은 1~3연초지에서는 Dactylis glomerata / Trifolium repens type, 4연초지에서 Imperata cylindrica / Trifolium repens type, 5~8연초지에서는 Imperata cylindrica / Zoysia japonica type으로 변화하였다. 2. 초장의 변화과정에서 혼파목초들은 1~3연초지까지는 길어지고 있으나(37.9~45.1cm) 그 이후부터 매년 짧아지고 있는 반면 잡초류의 초장은 1연초지 이후부터 현저히 길어지고 있는(30~44.2cm) 경향이었다. 3. 피도에 있어서 혼파목초들은 1 연초지에서 72.4%이던것이 해가 지남에 따라 극히 감소되어 8연초지에서는 0.2%로 나타나는 반면 잡초들은 1연초지 이후부터 현저히 증가되었다. 4. 연수의 경과에 따르는 식생구성률의 변화는 피도와 비슷한 경향이었다. 5. 초장 및 피도, 식생구성률에 있어서 해가 경과함에 따라 현저히 증가되는 식물은 Imperata cylindrica, Zoysia japonica, Miscanthus sinensis, Pteridium aquilinum, Crisium japonicum, Artemisia japonica 등이고 Cetella asiatica, Digitaria sanguinalis, Artemisia asiatica 등은 오히려 감소되었다. 6. 혼파목초지에 침범한 잡초유는 1연초지에서 24종이었으나 해가 경과함에 따라 종수가 증가되어 6연초지에서는 60종이었으며 그중 가축의 불식초류가 매년 증가되는 경향이었다. Mixed seeds of Dactylis glomerata, Festuca arundinacea, Trifolium repens, Lolium multiflorum on the improved pasture were sown to investigate the vegetational change during the years of 1971-1978. The dominant species were Dactylis glomerata and Trifolium repens from the first year to the third year, Imperata cylindrica and Trifolium repens in the forth year, Imperata cylindria and Zoysia japonica from the fifth year to the eighth year in the pasture.

靑馬의 現實對應과 虛無意志

趙南箕 同德女子大學校 1994 同大論叢 Vol.24 No.1

發情同期化 處理牛의 血中 性호르몬 및 代謝物質 水準 變化에 關한 硏究

曺南基,高在文 조선대학교 농업연구소 1988 農業硏究 Vol.1988 No.1

本 試驗은 韓牛 成牝牛의 發情同期化를 위하여 PGF₂α 處理時 發情發現, 血中 性호르몬 및 代謝物質 水準變化를 究明하기 위하여 25㎎의 PGF₂α를 11日 간격으로 2回 投與한 후 매일 採血한 다음 RIA法으로 性호르몬을 分析하였고, 代謝物質은 酵素分析法으로 分析하여 얻어진 結果는 다음과 같다. 1. PGF₂α 1次 處理後 平均 發情發現은 60.0±17.0 時間이 소요됐으나 2次 處理時는 55.2±16.1 時間이었다. 2. 血中 Progesterone 水準은 1次 및 2次 PGF₂α 處理時 各各 3.21±1.26ng/㎖과 2.63±1.24ng/㎖이었으나 24時間後(D₁)에는 各各 0.30±0.56ng/㎖과 0.37±0.61ng/㎖으로 急減하였다. 3. 血中 estradiol-17β 水準도 1, 2次 PGF₂α 處理日인 D?에는 各各 21.69±4.81ng/㎖과 21.77±4.11ng/㎖었으나 發情日인 D₂에는 24.67±2.79ng/㎖와 24.55±4.00ng/㎖으로 높아졌다. 4. PGF₂α 處理後 血中 總 Cholesterol 水準은 1, 2次 處理時 共히 發情日에 가장 높은 132.57±19.05ng/100㎖와 120.84±18.26ng/100㎖이었다. 5. 血中 總 蛋白質 水準은 PGF₂α 處理後 큰 變化가 없었으나 glucose는 發情日에 다소 높은 傾向이었다. 6. PGF₂α 處理時 血中 Progesterone 水準은 estradiol-17β, Cholesterol 및 glucose 水準과 高度의 ?의 相關(r=-0.91, r=-0.75, r=-0.76)이 存在하였다. This study was carried out to investigate the interactions of steroid hormones, metabolites and estrus in Korean native cows. The experimental cows were synchronized with inject ion of 25 mg PGF_2α in 11 days apart. Blood samples were collected every day to estrus after PGF_2α treatment. Serum steroid hormones were analyzed by RIA, and total cholesterol and glucose were analyzed by enzyme assay. The results obtained were as follows; 1. The estrus was induced at 60.0±17.0 hours after the first shot of PGF_2α and 55.2±16.1 hours after the second shot. 2. Serum progesterone levels at the 1st and the 2nd shot of PGF_2α were 3.21±1.26ng/ml and 2.63±1.24ng/ml, but significantly decreased to 0.3±0.56ng/ml and 0.37±0.61ng/ml at D_1, respectively. 3. In 2nd shot of PGF_2α, serum estradiol-17β level was 21.77±4.11pg/ml. but increased to 24.55±4.00pg/ml at estrus. 4. In estrus total cholesterol levels after 1st and 2nd shot of PGF_2α were increased to 132.57±19.05 and 120.84±18.26mg/100ml, respectively. 5. The correlation coefficients of progesterone with estradiol-17β. cholesterol and glucose were found to -0.91. -0.75 and -0.76 on day of 2nd shot of PGF_2α, respectively.

생쥐 및 소 受精卵의 分離方法에 關한 硏究

曺南基 조선대학교 농업연구소 1987 農業硏究 Vol.1987 No.1

本 試驗은 受精卵의 徵細分離 및 培養에 대한 基礎資料를 얻고자 생쥐의 2, 4, 8 및 桑實胚와 소의 桑實胚를 供試하여 0.5%의 Pronase 處理 및 徵細操作器를 利用한 受精卵 分離 및 分離卵 培養試驗을 한 結果는 다음과 같다. 1. 多排卵 誘起를 위하여 생쥐는 PMS와 HCG를 各各 5 IU, 소에서는 PMS 2,500 IU와 PGF₂α×25㎎을 처리하여 頭當 各各 19.7±6.3個 및 7.5±3.1個의 正常受精卵을 回收하였다. 2. 供試된 總 個의 생쥐 受精卵 中 2細胞期에서 完全分離率은 75.0%였고, 平均은 70.5%였으며 소의 桑實胚는 66.7%가 完全分離되었다. 3. 分離된 생쥐 受精卵을 培養하여 正常發達을 나타낸 것은 2, 4, 8 및 桑實胚에서 各各 69.1%, 71.4%, 57.9% 및 69.2%였고 소의 桑實胚는 66.7%로 全體 平均은 67.9%였다. This study was carried out to obtain the basic information Oil splitting and culture of mouse and bovine embryos. Two-, fourh-, eight- cell and morula mouse embryos were digested by pronase, splitted in vitro by micro-glass needle with hand, and bovine embryo was splitted by micromanipulator. The splitted embryos were cultured under 5% of CO_2 gas in air at 37℃ for 48~72 hours. The results obtained in this study were summerized as follows; 1. The mouse and cattle were superovulated by 5IU of PMS and HCG, and 2,500IU of PMS and 25mg of PGF_2, respectively. The average embryos superovulated were 32.5±8.2 and 7.5±3.1, respectively. 2. Out of total 122 embryo splitted, the successful splitting rate was 75.0%, 66.7%, 68.4$ and 71.4% in 2-, 4-, 8- and morula embryos in mouse, respectively. There was no different splitting rate between mouse(71.4%) and bovine embryos (66.7%) in morula. 3. The successful culture rate of splitted embryos was 6P.0% and 67.9% in mouse and bovine embryos, respectively.

소에 있어서 雙胎生産에 관한 硏究

曺南基 조선대학교 농업연구소 1986 農業硏究 Vol.1986 No.1

본 硏究는 소에 있어서 송아지 壙大增殖을 위한 方案으로 雙胎生産을 위한 自然雙胎誘起 方法과 人爲的 雙胎生産 方法을 近來 論文 考察을 통하여 檢討하였고 雙胎誘起로 인하여 생기는 雙胎 송아지 生産이 分娩形質에 미치는 영향 등을 考察하였다. 1. 育種的인 면에서 雙胎出産은 낮은 遺傳力과 反復力 때문에 自然選拔에 의한 雙胎誘起 方法은 거의 活用할 수 없다. 2. 人爲的인 雙胎出産은 hormone 處理에 의한 方法보다 受精卵 利殖에 의한 방법이 더 좋은 結課를 얻었다. 3. 雙胎分娩시 難産, 後産 정체, 空胎期間 등이 單胎分娩시 보다 훨씬 增加하였다. This paper was reviewed on the methods of natural and artificial twinning in cattle and the calving characteristics of twins. 1. The possibility of selection for twins would not appear to be a likely candidate because of low heritability and repeatability. 2. The results obtained from embryo transfer for twin production of cattle were better than those from hormone treatment. 3. The dystocia, retained placentas and longer rebreeding intervals in twin production were increased much higher than those in single.

제주지역에서 파종량 차이에 따른 귀리의 생육특성 , 사초수량 및 조성분 변화

조남기,조영일,송창길,송승운,오은경 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.4

Oats was grown at five seeding rates(90, 110, 130, 150 and 170㎏/㏊) from Nov. 8, 1998 to June 8, 1999 at Jeju island to determine influence of seeding rate on agronomic characters and forage yield and quality. Days to heading and days to maturing increased 164-166 and 206-208 days as seeding rate increased from 90 to 170㎏/㏊. The plant height increased from 118.5 to 122.6㎝ as seeding rate was increased from 90 to 150㎏/㏊ and then decreased to 122.1㎝ at a rate of 170㎏/㏊. This pattern held for leaf length, leaf width and culm length which were greatest in four seeding rate respectively, but no. of grains per panicle and no. of spikelet per panicle which were decreased as seeding rate increased from 90 to 170㎏/㏊. As seeding rate increased from 90 to 150㎏/㏊, fresh forage, dry matter, crude protein and total digestible nutrients(TDN) yield increased from 29 to 43.43, 4.77 to 8.27, 0.55 to 1.10 and 2.33 to 4.39MT/㏊, respectively, and then decreased with further increased seeding rates. Grain yield was increased from 1.33 to 6.10MT/㏊ as seeding rate was increased from 90 to 130㎏/㏊ and then decreased from 5.50 to 4.50MT/ha at the 150 and 170㎏/㏊ seeding rates. Test weight and 1,000 grains weight decreased as seeding rate was increased. Crude protein, ether extract, nitrogen free extract and TDN content increased 11.5 to 13.8%, 2.0 to 3.1%, 37.6 to 39.2%, 48.8 to 54.2% respectively, but crude fiber content decreased 35.1 to 32.2% and crude ash declined 8.5 to 6.5% as seeding rate increased from 90 to 170㎏/㏊. The optimum seeding rate to obtain the highest TDN yield was estimated to be 167.5㎏/㏊.

干拓地에서 栽培한 설탕무우 Silage가 育成豚의 成長에 미치는 效果

曺南基,金泰光 조선대학교 농업연구소 1985 農業硏究 Vol.1985 No.1

本 試驗은 育成豚에 對한 설탕무우 사일레지의 飼料價値 및 適正 給與水準을 究明하기 위하여 실시하였다. 즉 설탕무우 사일레지를 0, 15, 30, 45, 그리고 60% 까지 代置 給與하여 三元雜種(Nandrace × Chester white × Yorkshire), 30頭를 供試하고 約80日間으 飼養試驗을 實施하였던 바 그 結果를 要約하면 다음과 같다. 1. 총 增體量은 설탕무우 사일렌지 給與水準이 0, 15, 30, 45, 그리고 60%로 높아짐에 따라 각각 56.9, 57.1, 57.2 그리고 59.6kg으로서 큰차이가 없었다. 2. 日당 增量은 處理區別로 705, 707, 708 및 738g으로서 설탕무우 사일렌지 水準 增加에 따라 같거나 다소 높은 경향이나 統計的인 有意差는 인정되지 않았으며 飼料要求量도 3.83, 3.81, 3.89, 3.89 및 3.76kg으로서 차이가 없었다. 3. 설탕무우 사일렌지 水準增加에 따라 등지방이 얇아지는 경향이었으며, 4. 增體kg當 飼料費는 설탕무우 사일렌지를 많아 給與하였을때가 가장 經濟的이었다. 5. 以上의 結果로 볼때 설탕무우 사일렌지를 곡류와 代置하여 60%까지 給與하여도 좋은 것으로 思料된다. Thirty erossbred pigs (Landrace x Chestwhite x Yorkshire) were used to study the effect of sugarbeet silage (0, 15, 30,45,60 %) as a replacement of grains in rations from weanling to marlcet weight on the .dry lot performance, carcass quality and feed cost per kg gain. The results obtained are as follows. 1. Body weight gain for 0, 15, 30, 45 and 60 % level of sugarbeet silage were 56. 9, 57, 1, 57.1, 57.2 and 59.6kg respectively. 2. Average daily gain was 705, 707, 707, 708 and 738kg respectively and tended to increase as the level of sugarbeet silage in the ration increased. However, there were on satistical differences between the levels. The amount of feed required per kg gain were 3. 83, 3. 81, 3. 89, 3. 89 and 3. 76kg respectively. 3. As the level of sugarbeet silage increased, back fat thickness tended to thin. 4. Feed cost per kg gain was the cheapest at the highest level of sugarbeet silage used. 5) Above result indicate that up to 60 % level of sugarbeet silage in the rations gave satisfactory gains, feed efficiency, carcass quality and feed cost per kg gain. The effect of sugarbeet silage in growing finishing pigs ration on performance and .carcass quality was studied. Up to 50 % level of sugarbeet silage in the ration indicated satisfactory results.

濟州道 混播收草地의 雜草遷移에 관한 硏究 : Ⅰ. 엉겅퀴(Cirsium japonicum)의 李節 및 年次的 變化

趙南棋 제주대학교 1984 논문집 Vol.18 No.-

本 硏究는 濟州道 漢拏山 中山間地域의 自然草地(Imperata cylindrica / Zoysia japonica type)를 開墾한 後 Dactylis glomerata 17kg, Festuca arundinacea 7kg, Lolium multiflorum 2kg, Trifolium repens 2kg의 導入牧草를 混播하여 (28kg/1 ha) 家畜放牧에 利用되고 있는(1977∼1982年) 改良牧草地를 對象으로 하여 엉겅퀴(Cirsium japonicum)의 季節 및 年次的 生育變化過程을 調査한 結果를 要約하면 다음과 같다. 1. Cirsium japonicum의 季節에 따르는 密度ㆍ被度ㆍ草長ㆍ收量 등 植生의 季節的 變化는 各年度마다 秋期에 가장 優勢하였고, 春期에는 가장 低調하였다. 2. 草長의 年次的 變化는 1年草地에서 39.89cm였으나 年數가 經過함에 따라 점차적으로 增加되어 6年草地에서는 50.42cm로 나타나고 있는데, 이 變化狀態의 回歸方程式은 y=0.03x²+2.28x+35.62였다. 3. 草地造成 以後 年次別 密度의 變化는 1年草地에서 0.08%였던것이 6年草地에서는 0.29%로 增加(y=0.01x²-0.02x+0.15)되었다. 4. 被度의 年次的 變化는 1年草地에서 0.54% 였던 것이 年數가 經過함에 따라 점차 增加되어 6年째 되는 草地에서는 3.01%로 나타나고 있는데, 이 變化狀態는 y=0.16x²+0.02x+0.38이었다. 5. 年數의 經過에 따르는 生草收量의 變化는 10a當 1年草地에서 2.40kg이었으나, 6年草地에서는 11.37kg으로 每年 增加되는 傾向(y=0.08x²+1.25x+1.07)이었다. This study was conducted to examine the yearly and seasonal changes of Cirsium japonicum in the improved pasture of the mountain districts around Mt. Halla in Cheju Island. For this study, the researcher and investigated for six years from 1977 to 1982 the improved pasture which had been used for grazing from 1977 to 1982. The pasture was reclaimed from native grassland. The mixed seeds of 17kgs' Dactylis glomerata, 7kgs' festuca arundinacea, 2kgs' Lolium multiflorum and 2kgs' Trifolium repens were showed per 1 ha. The results of this study are the following: 1. The seasonal changes of Cirsium japanicum : its length, weight, density and coverage are heighest in autumm, and are lowest in spring every year. 2. The yearly change in the length of Cirsium japonicum : its length is gradually increased from 39.89cm in the first year after the reclaimation to 50.42cm in the sixth year. This change can be represented by the regression equation, y=0.03x²+2.28x+35.62. 3. The yearly change in its density : its density is rapidly increased from 0.08% in the first year to 0.29% in the sixth year. The results of this change can be obtained with the regression equation, y=0.01X²-0.02X+0.15. 4. The yearly change in the coverage : its coverage is increased year by year from 0.54% in the first year to 3.01% in the sixth year. This change can be calculated with regression equation, y=0.16X²+0.02X+0.38. 5. The yearly change in its weight : the weight is also increased year after year from 2.40kg in the first year after reclaimation to 11.37kg in the sixth year. This change can be calculated with the regression equation of y=0.08X²+1.25X+1.07.

濟州道人工草地 植生의 經時的變化에 관한 硏究 : Ⅲ. 優占種의 李節 및 年次的 變動 Ⅲ. The Seasonal and Annual Changes in Dominant Species

金翰琳,宋昌吉,趙南祺 濟州大學校 1982 논문집 Vol.14 No.-

本 硏究는 濟州道 漢拏山 北麓海拔 350m에 位置하여 있는 自然草地를 開懇한 後 Dactylis glomerata. Festuca arundinacea. Trifolium repens等의 牧草를 混播하여 家畜放牧에 利用되고 있는 人工草地의 優占植物에 대하여 季節的·年次的 變動狀態를 調査한 結果를 要約하면 다음과 같다. 1. 春期의 優占種의 變動은 1975年에 Dactylisglomerata>Lolium multiflorum>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea 順位이고, 1976年에는 Dactylis glomerata>Trifolium repens>Festuca arundinacea>Hydrocotyle japonica>Artemisia asiatica, 1977年은 Dactylis glomerata>Trifolium repens>Festuca arundinacea>Hydrocotyle japonica>Rumex acetocella, 1978年에는 Trifolium repens>Dactylis glomerata>Imperata cylindrica>Zoysia japomica>Festuca arundinacea, 1979年에는 Imperata cylindrica>Trifolium repens>Zoysia japonica>Dactylis glomerata>Rumex acetocella, 1980年에는 Imperata cylindrica>Zoysia japonica>Trifolium repens>Rumex acetocella>Cerastium holosteoides의 順位를 보였다. 2. 夏期의 優占種의 變動은 1975年에 Dactylis glomerata>Hydrocotyle japonica>Trifloium repens>Digitaria sanguinalis>Lolium multiflorum順位이고, 1976年에는 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Digitatia sanguinalis>Festuca arundinacea, 1977年에는 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Zoysia japonica, 1978年에는 Trifolium repens>Imperata cylindica>Zoysia japonica>Dactylis glomerata>Hydrocotyle japonica, 1979年에는 Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Rumex acetocella, 1980年에는 Imperata cylindrica>Zoysia japonica>Rumex acetocella>Hydrocotyle japonica>Trifloium repens 順位를 보였다. 3. 秋期의 優占種의 變動은 1975年에 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Digitaria sanguinalis>Festuca arundinacea 順位이고, 1976年 Dactylis glomerata>Trifolium repens>Hydrocotyle japonnica>Festuca arundinacea>Zoysia japonica, 1977年 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Zoysia japonica>Festuca arundinacea, 1978年 Trifolium repens>Imperata cylindrica>Zoysia japonica>Dactlis glomerata>Hydrocotyle japonica, 1979年 Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea, 1980年에는 Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydorocotyle japonica>Miscanthus sinensis 順位였다. 4. 年次的인 優占種의 變洞은 1975年에 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Lolium multiflorum>Digitaria sanguinalis 順位이고, 1976年 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Digitaria sanguinalis, 1977年 Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Zoysia japonica, 1978年 Trifolium repens>Imperata cylindrica>Dactylis glomerata>Zoysia japonica>Hydrocotyle japonica, 1979年 Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Dactylis glomerata順位였다. This study was conducted to investigate the annual and seasonal changes in dominant species on the improved pasture at an altitude of 350m around Mt. Halla during the six years from 1975 to 1980, which was used for grazing after reclaimed from native grassland and sowed with the mixed seeds of Dactylis glomerata, Festuca arundinacea, Trifolium repens, etc. The results obtained are summarized as follows; 1. Spring, 1975; Dactylis glomerta>Lolium multiforum>Trifolium repens> Hydrocotyle japonica>Festuca arundinacea. 1976;Dactylis glomerata>Trifolium repens>Festuca arundinacea>Hydrocotyle japonica>Artemisia asiatica 1978;Trifolium repens>Dactylis glomerata>Imperata cylindrica>Zoysia japonica>Festuca arundinacea. 1979;Imperata cylindrica>Trifolium repens>Zoysia japonica>Dactlis glomerata>Rumex acetocella, 1980; Imperata cylindrica>Zoysia japonica>Trifolium repens>Rumex acetocella>Cerastium holosteoides. 2. Summer, 1975;Dactylis glomerata>Hydrocotyle japonica>Trifolium repens>Lolium multiflorum, 1976; Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Digitaria sanguinalis>Festuca arundinacea 1977;Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Zoysia japonica 1978;Trifolium repens>Imperata cylindrica>Zoysia japonica>Dactulis glomerata>Hydrocotyle japonica 1979;Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Rumex acetocella. 1980;Imperata cylindrica>Zoysia japonica>Rumex acetocella>Hydrocotyle japonica>Trifolium japonica>Trifolium repens. 3. Autumn, 1975;Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Digitaria sanguinalis>Festuca arundinacea. 1976;Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Zoysia japonica 1977;Dactylis glomerata>Trifolum repens>Hydrocotyle japonica>Zoysia japonica>Festuca arundinacea. 1978;Trifolium repens>Imperata cylindrica>Zoysia japonica>Dactylis glomerata>Hydrocotyle japonica. 1979;Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea 1980; Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Mixcanthus sinensis. 4. Yearly, 1975; Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Lolium multiflorum>Digitaria sanguinalis 1976; Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Digitaria sanguinalis 1977; Dactylis glomerata>Trifolium repens>Hydrocotyle japonica>Festuca arundinacea>Zoysia japonica. 1978;Trifolium repens>Imperata cylindrica>Dactylis glomerata>Zoysia japonica>Hydrocotyle japonica. 1979; Imperata cylindrica>Zoysia japonica>Trifolium repens>Hydrocotyle japonica>Dactylis glomerata.

질소분시가 청예피의 생육특성 , 수량 및 조성분 함량에 미치는 영향

조남기,강영길,부창훈 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.2

This study was conducted at a volcanic ash soil of Jeju island in 1999 to determine the optimum frequency of split N application for forage production of Japanese millet [Echinochloa crusgalli var. frumentacea (Roxb.) W. F. Wight]. Nitrogen fertilizer was applied with 200 ㎏ N/㏊, and frequencies of the split applications were 1, 2, 3, 4 and 5 times. A Jeju native cultivar of Japanese millet was planted at a rate of 30 ㎏ seed/㏊ on 31 May, and harvested on 6 September. Days to heading increased from 84 to 88 days as N was split-applied from one to five applications. Plant height increased from 152 to 188 cm as N was split-applied from one to three applications and then decreased to 156 cm in five applications. This pattern held for leaf length, leaf width, and stem diameter which were greatest in three applications with 42.4, 2.6, and 0.67 ㎝, respectively. Green leaf number was 10 regardless of the treatments. Dry matter (DM) yield increased from 6.96 to 11.99 MT/㏊, crude protein (CP) yield from 0.47 to 0.89 MT/ha, and total digestible nutrients (TDN) yield from 3.80 to 6.81 MT/㏊ as N was split-applied from one to three applications, and then decreased to 7.51, 0.63 and 4.43 MT/ha, respectively, in five split applications. Nitrogen uptake increased from 75.1 to 142.9 ㎏/㏊ as N was split-applied from one to three applications and then decreased to 101.3 ㎏/㏊ in five split applications. Nitrogen use efficiency decreased from 92.8 to 74.1 ㎏ DM/㎏ N with increasing split N application. Crude protein content increased from 6.7 to 8.4%, ether extract content from 5.7 to 6.1%, nitrogen free extract content from 30.7 to 34.7%, and TDN content from 48.0 to 53.0%, but crude ash content decreased from 10.2 to 8.0% and crude fiber from 38.9 to 35.5% as N was split-applied from one to five applications. These results indicate that the optimum frequency of split N applications is three times for forage production of Japanese millet in volcanic ash soils of Jeju island.