In order to examine the possibility that oil seed rape could be used as a forage fodder crop and to select the most suitable variety of forage rape at the southern area of Korea, two varieties of oil seed rape currently grown for oil production and six introduced varieties of forage rape with relatively high yield and high nutritional value were grown at the same condition and their nutritional value were observed. Generally, rape was considered as a useful forage fodder crop with high content of crude protein and low contents of NDF, ADF, hemicellulose, cellulose and lignin. Differences in mean values of the above characters between two groups of rape were not statistically significant. Velox showed significantly higher content of crude protein and significantly lower contents of NDF, ADF, hemicellulose, cellulose and lignin compared with other varieties of forage rape. Rape was relatively high in IVDMD compared with other forage fodder crops, and forage rape was more or less higher in IVDMD and DDMM than oil seed rape. Velox was the highest in IVDMD and DDMM among the varieties of forage rape in this experiment.

남부지역에 적응한 사초용 유채의 춘파 품종을 선발하기 위하여 3월 25일에 파종한 그 결과는 다음과 같다. 1. 다수성이며 조단백질 함량과 in vitro dry matter digestibility(IVDMD)가 높고 NDF, ADF, cellulose 및 lignin 함량이 낮아서 영양가가 우수한 춘파 용 사초 유채는 Velox 품종이었다. 2. Velox품종은 초장이 길고 경태가 두꺼웠으며 주경의 잎도 많았고 생체중 과 총건물수량이 가장 많았다. 3. 모든 형질에 대한 유전력은 대부분의 형질에서 높았으나 hemicellulose에서만이 낮게 평가되었다.

To determine as optimal sowing time of forage rape in spring time in southern areas of Korea, forage rape cv. Velox, the highest yielding variety among introduced varieties of forage rape, was grown under five different sowing times. Yield components such as plant length, number of branches and number of leaves etc. were higher at the sowing time of Mar. 15 and Mar. 25. The plants sown at Mar. 15 and Mar. 25 also showed highest fresh and dry matter yield. When plants were grown under later sowing time, they showed higher values in content of crude protein and lower values in contents of crude fiber such as Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), cellulose and lignin. There was no relationship between variation of In Vitro Dry matter Digestibility (IVDMD) and sowing time. The plants sown at Mar. 15 and Mar. 25 showed highest digestible dry matter yields.

Four introduced forage rape (Brassica napus) cultivars, 'Akela', 'Ramon', 'Sparta', and 'Velox' and a leading rapeseed cultivar, 'Hallayuchae' were grown at nitrogen (N) rates of 0, 100, 250, 300, 350, and 400 kg/ha to (i) select forage rape cultivars adapted best to Cheju area, and (ii) determine the optimum N rate for the best cultivars. Days from seeding to flowering across the cultivars increased 190 to 195 days as N rate increased from 0 to 400 kg/ha. Average days to flowering of six cultivars ranged from 182 to 198 days. Plant height increased as N rate increased up to 300 kg/ha and then decreased with a further increase in N rate and ranged from 159 to 174 cm among the cultivars. The optimum N rate for the greatest dry matter yield of five cultivars ranged from 222 to 258 kg/ha. Sparta showed the greatest dry matter yield (35.79 Mg/ha), followed by Akela, Hallayuchae, Velox, and Ramon. As N rate increased, crude protein content linearly increased but crude fiber content declined curvilinearly. Akela and Sparta had higher protein content than the other cultivars did. The forage cultivars had lower crude fiber content than the oilseed cultivar Hallayuchae did. Our results demonstrated that Sparta was best adapted to Cheju area and the optimum N rate for Sparta was about 220kg/ha.

Four introduced forage rape cultivars 'Akela', 'Ramon', 'Sparta', and 'Velox' and a leading rapeseed cultivar Hall-ayuchae were seeded on 1 October 1994 on 20-cm rows at seeding rates of 3, 5, 7, 10, 13, and IS kg/ha to select the best adapted forage rape cultivars and to determine the optimum seeding rate in the Cheju area. Days to flowering of each cultivar was not significantly affected by seeding rate. Average plant height increased from 151 to 164 cm as seeding rate increased from 3 to 10 kg/ha and then decreased to 156 cm at 15 kg/ha. Stem diameter linearly decreased with increasing seeding rate. The optimum seeding rate for the greatest dry matter and protein yields of five cultivars ranged from 10.7 to 11.8 and 10.8 to 14.4 kg/ha, respectively. Dry matter yields of five cultivars ranged from 7.72 and 22.01 Mg/ha. Sparta produced the greatest dry matter yield, followed by Akela, Ramon, Hallayuchae, and Velox. Crude protein yields of five cultivars ranged from 0.29 to 1.08 Mg/ha. Sparta produced the greatest crude protein yield, followed by Akela, Ramon, Velox, and Hallayuchae. As seeding rate increased, crude protein content linearly increased but crude fiber content linearly decreased. The forage cultivars had higher crude protein and lower crude fiber than the oilseed cultivar Hallayuchae. Our results demonstrate that Sparta was the best adapted cultivar to Cheju area and the optimum seeding rate for Sparta was about 10 kg/ha.

본 시험은 남부지방에 적합한 사초용유채의 파종기별 예취시기가 수량 및 영양가치에 미치는 영향을 구명하기 위하여 Velox를 공시하여 실험하였던바 그 결과를 요약하면 다음과 같다. 1. 경태를 제외한 초장, 분지수, 주경엽수의 형질들은 파종기와 예취시기가 늦을수록 우수하였다. 2. 생초수량은 9월 하순에 파종하여 개화기인 4월 하순에 예취한 구가 가장 높았으며, 건물수량은 파종기와 예취시기가 늦을수록 높아서 9월 하순에 파종하여 만개기인 5월 초순에 예취한 구가 가장 높았다. 3, 조단백질함량은 파종기가 늦을수록 높았고, 예취시기는 늦을수록 급격히 저하되었으며, 9월 하순에 파종하여 추태기인 4월 초순에 예취한 구가 가장 높았었다. 4. NDF, ADF, hemicellilose, cellulose 및 lignin 등의 조섬유함량은 파종기가 늦을수록 저하되었고, 예취시기가 늦을수록 높았었다. 5. IVDMD은 조섬유와 같은 경향이었고, 가소화건물수량은 9월 하순에 파종하여 개화기인 4월 하순에 예취한 구가 가장 높았었다.