본 연구는 평창지역의 산지에서 목초 파종시기가 초지의 연차별 식생 및 생산성에 미치는 영향을 구명하고 평창지역의 산지초지 조성에 적합한 피종시기를 설정하고자 2015년 8월부터 2017년 10월까지 평창군에 위치한 서울대학교 국제농업기술대학원의 산지에서 수행되었다. 처리는 총 4처리로 T1: 8월 13일 파종 T2: 8월 27일 파종, T3: 9월 10일 파종, T4: 9월 24일 파종이었다. 월동 후 초지 식생구성을 보면 T1과 T2까지는 목초 식생비율이 98%이상으로 높은 식생밀도를 보였지만 T3이후부터는 급격하게 감소하였다. 분얼의 경우 T1과 T2에서 4.4개 이상으로 양호하였지만 T3이후에는 급격하게 감소하였다. 이러한 초기 월동률의 차이는 이후 목초의 식생 및 생산성에 큰 영향을 주었다. 연차별 식생변화를 보면 T1과 T2의 경우 목초 비율이 81%이상으로 우수하였지만 T4의 경우 상대적으로 불량하였다. 전체 건물 수량의 경우 T2와 T1이 각각 9,042 kg ha-1 와 8,845 kg-1 로 우수하게 나타났지만 T4의 경우 5,086 kg ha-1 로 건물 생산성이 상대적으로 낮게 나타났다. 결과를 종합해보면 평창지역에서 8월 말까지 파종을 완료 한 경우 목초 월동이 향상되었으며 이는 식생이나 생산성 측면에서 유리하게 나타났다.

본 연구는 이탈리안 라이그라스 품종별 내한성 및 생육특성의 변화와 그에 따른 생산성 변화요인을 분석하기 위하여 2017년부터 2018년까지 우리나라 중부지역인 충남 천안에서 수행되었다. 이탈리안 라이그라스의 월동율은 품종 간에 차이가 있었으며(p<0.01), 외국품종보다 국내품종이 대부분 월동이 잘되었다. 조생종에서는 코윈어리의 월동율이 68%로 가장 높았고, Florida 80의 월동율이 35%로 가장 낮았으며, 중생종에서는 코윈마스터의 월동율이 70%로 가장 높았고, 외국품종인 Tam 90이 42%로 가장 낮았다(p<0.05). 외국품종 중에서는 Winter-hawk가 57% 월동하여 다른 외국 품종보다 월동율이 높았다. 건물수량은 품종 간 차이가 많았다(p<0.05). 조생종 중에서는 내한성이 강한 국내품종인 그린팜 2호와 코윈어리가 외국품종인 Florida 80보다 건물수량이 약 3~3.5톤/ha 많았다. 중생종 중에서는 내한성이 강한 국내품종인 코윈마스터가 외국품종인 Winter-hawk나 Tam 90보다 건물수량이 약 2톤/ha 많았다(p<0.05). 이탈리안 라이그라스의 내한성은 건물생산성과 고도의 정의상관이 있었다(p<0.01). 우리나라 중부지역에서 이탈리안 라이그라스를 5월 중순에 수확을 완료해야 한다면, 내한성이 강한 국내 육성 조생 또는 중생품종을 선택하여 재배하는 것이 양질 조사료 생산성 향상에 유리할 것으로 사료된다.

This study was conducted to explore the effects of seeding rate of a seed mixture on grassland productivity and botanical composition. Seeding rates were composed of four different treatments varying by the amount of seed: T1, 50% decrease in seeding rate from standard; T2, standard seeding rate; T3, 50% increase in seeding rate from standard; and T4, 100% increase in seeding rate from standard. In 2016, seasonal changes in grass botanical composition revealed T2, T3, and T4 in portion of grass ratio were the highest with a range of 87–100%, whereas T1 was the lowest of all treatments. In 2017, the botanical composition in T1 showed that the grass ratio in of the first cutting was 91%, but in the fourth cutting its ratio decreased by 75%. The results from both years were combined for each treatment, T4 (11,435 kg ha-1) and T3 (11,162 kg ha-1) demonstrated the highest dry matter yield of the treatments (T1: 8,196 kg ha-1; T2: 9,521 kg ha-1) (p＜0.05). As a result, a 50–100% increase in the seeding rate from the standard demonstrated the best grassland yield and botanical composition.

This study was carried out to introduce of agronomic characteristics, forage yields and quality of Sorghum × Sudangrass hybrids ‘Cadan 99B’ and ‘Sweet Sioux WMR’ from 2015 to 2016 in middle and southern regions of Korea. The field experiment design was complete in seven varieties with three repetitions. Sorghum × Sudangrass hybrids were sown on mid-May in middle region, and end-May in southern region of Korea, in 2015 and 2016. The observed average heading date of Cadan 99B and Sweet Sioux WMR were July 22. The heading dates of Cadan 99B and Sweet Sioux WMR were 8 days earlier than SX-17 and 5 days earlier than brown mid-rid (BMR) Revolution. The sugar contents of Cadan 99B and Sweet Sioux WMR were 6.5 and 6.9 Brix°, respectively. Comparison with BMR variety, the sugar contents of Candan 99B and Sweet Sioux WMR were 0.2 and 0.6 Brix° higher than Revolution, respectively. The average of dry matter (DM) yield for 2 years and 2 regions of Cadan 99B (24,587kg/ha) were the highest among the seven varieties, but there was no significant difference among other varieties except headless control variety Jumbo (19,119kg/ha) and LATTE (20,778kg/ha) (p>0.05). The crude protein (CP) and in vitro dry matter digestibility (IVDMD) of Cadan 99B were 7.5% and 60.2%, and Sweet Sioux WMR were 6.9% and 60.7%, respectively. The results of this study indicated that Sorghum × Sudangrass hybrids Cadan 99B and Sweet Sioux WMR are earlier heading dates and higher than SX-17, and high yields of DM in middle and southern regions of Korea.

This study was conducted to find out the effects of over seeding using new grass varieties orchardgrass ‘Kordione’ and ‘Onnuri’, and tall fescue ‘Greenmaster’ on botanical composition and dry matter productivity from 2013 to 2016 in low productivity hilly pasture, middle area of Korea. There were used 3 grass seed mixture types made of different compositions and amounts {T1: control - no over seeding, T2: tall fescue (TF) ‘Greenmaster’ 18 kg ha-1, orchardgrass (OG) ‘Kordione’ 9 kg ha-1, Perennial ryegrass (PRG) ‘Linn’ 5 kg ha-1, and Kentucky bluegrass (KBG) ‘Kenblue’ 2 kg ha-1, T3: TF ‘Greenmaster’ 9 kg ha-1, OG ‘Kordione’ 18 kg ha-1, PRG ‘Linn’ 5 kg ha-1, and KBG ‘ Kenblue’ 2 kg ha-1, T4: TF ‘Greenmaster’ 9 kg ha-1, OG ‘Onnuri’ 18 kg ha-1, PRG ‘Linn’ 5 kg ha-1, and KBG ‘Kenblue’ 2 kg ha-1}. In the botanical composition of grassland, T1 nearly remained constant in other seasons while ratio of weeds were increased in summer season. T2 was better than control (T1) in portion of grass ratio, which has increased by 80%. In the early time of establishment, the portions of OG were increased in T2, but TF rate was increased after 3 years later when grass was established. T3 and T4 showed a very similar patterns, grass ratio had increased by 80% and the portion of KBG had increased as time passed. T2 (129,763 kg ha-1) was showed the highest dry matter yield than other treatments (T1: 6,756 kg ha-1, T3: 9641, and T4: 10,738) in 2016.

This experiment was carried out to compare the growth characteristics and productivity between sudangrass and sorghum-sudangrass hybrid under the same cultivation condition in Cheonan and Kimje of Korea from 2010 to 2011. Sudangrass hybrids(Choice, Sunstar and Piper) and sorghum-sudangrass hybrids(SX-17, Jumbo and Revolution) were planted 5th May in Cheonan and 7th May in Kimje. Heading date of sudangrass hybrids was 12th July which was about 2 week fast more than that of sorghum-sudangrass hybrids. Stem diameter of sudangrass hybrids was about 6mm which was about 5 mm smaller than that of sorghum-sudangrass hybrids. Disease resistance of sudangrass hybrid, “Choice” was similar to that of sorghum-sudangrass hybrids. Dry matter yield of “Choice” was 15ton/ha which was 10% less than that for sorghum-sudangrass hybrids(SX-17). Feed value of “Choice” was similar or slightly lower than that of sorghum-sudangrass. For increasing the productivity in forage cropping systems all around year, sudangrass hybrid is recommended for prolong by the middle ten day of May in the harvesting time of italian ryegrass

This experiment was carried out to study the effect of rice black-streaked dwarf virus(RBSDV) infection rate on forage productivity of corn varieties in Cheonan of chungcheongnamdo from 2006 to 2008. Forage corn varieties of 10 were cultivated with first cropping(seeding in the last ten days of April) and second cropping(seeding in the last ten days of May) system in field and tested the infection rates of RBSDV and productivity of forage. The Infection rate of RBSDV was significant difference between corn varieties in middle district of Korea. Resistant corn varieties for RBSDV were ‘Kwanganok’, ‘P3156’, ‘Kwangpeyongok’ and ‘P3394’ but susceptible varieties were ‘Suwon19’, ‘DK697’, ‘GW6959’ and NC+7117. Dry matter(DM) yield of forage corn according with infection rates of RBSDV in field was significant difference between varieties(p<0.05). DM yield of susceptible varieties, ‘Suwon 19’, ‘DK697’ and ‘GW6959’ was lower about 20% than that of resistant varieties, ‘Kwangpeyongok’ and ‘P3156’. For increasing the productivity of forage corn, recommend of resistant varieties for RBSDV and control of seeding time are very important in middle district of Korea.

The objective of this study was to determine the effect of harvesting time of rice on growth characteristics and dry matter yields of Italian ryegrass (Lolium multiflorum Lam., IRG) ‘Kowinearly’ after seeding them in paddy field. Experiments were performed in National Institute of Animal Science, RDA (Cheonan, Choongcheongnam-do province of Korea) for four years (2011~2014). Italian ryegrass variety ‘Kowinearly’ was seeded at experimental paddy fields before rice harvest in late September. Rice were harvested at 10, 20, and 30 days after seeding of IRG. As the harvest time of rice became later, the number of tillering before winter was reduced and IRG plant length before winter was shorter. The dry matter yield of IRG was also reduced. When rice were harvested at 20 days and 30 days after sowing of IRG compared to the rice harvested in autumn at 10 days after sowing of IRG, the number of tillering for IRG before winter was decreased by an average of 19% and 40%, respectively. The winter survival ratio of IRG was decreased by an average of 13% and 19%, respectively. Their dry matter yields were also reduced by an average of 8% and 19%, respectively. The heading date was different from each other in three years. The plant length at the time of IRG harvest in the spring was not significantly different among treatment groups. Taken together, our results suggest that when Italian ryegrass is grown in paddy fields by the method of ‘seeding of IRG before rice harvest’, rice should be harvested as soon as possible after sowing of IRG ‘Kowinearly’ in the autumn to increase forage productivity.

This study was conducted to evaluate the growth characteristics and dry matter yields of Italian ryegrass (Lolium multiflorum Lam., IRG) cultivars for three years (2011~2013). The cold-resistance of domestic cultivars was stronger than other foreign varieties. Among early-maturing cultivars, dry matter (DM) yield of ‘Kowinearly’ was significantly higher (8,751 kg/ha) than other cultivars (p<0.05). In medium-maturing cultivars, DM yield of ‘Kowinmaster’ and ‘Tam 90’ was 9,394 and 7,461 kg/ha, respectively. Of the two, the former’s DM yield was higher than the latter’s (p<0.05). Among late-maturing cultivars, DM yield of ‘Hwasan 104’ (9,809 kg/ha) was similar to ‘Hwasan 101’ (9,354 kg/ha), but significantly higher than the other late-maturing cultivars (p<0.05). According to the results obtained from present study, early-maturing cultivars with cold-tolerance and high productivity is required for the paddy field cultivation of an Italian ryegrass cultivar after rice harvest in Cheonan region. Medium- and late-maturing cultivars are more advantageous for the dry field cultivation of the maximum quantity that is possible. In conclusion, to select which cultivar/s to grow, the climate of the growing area, weather conditions, and the cropping system must all be considered