초록
본 연구는 2012년부터 2014년까지 국립축산과학원 축산자원개발부 초지사료과 시험포장(충남 천안, 논)에서 이탈리안 라이그라스를 벼 입모중 파종 후 벼 수확시기에 따른 이탈리안 라이그라스의 생육특성 및 조사료 생산성을 평가하기 위해 수행하였다. 국내육성 이탈리안 라이그라스 조생종 '코윈어리'를 9월 하순에 파종 후 10일 간격으로 3회에 나누어 벼를 수확해서 재배하였을 때, 벼 수확시기가 늦어짐에 따라 월동 전 분얼수, 월동 전 초장, 월동률 및 건물수량 모두 감소하는 것으로 나타났다. 가을에 벼를 IRG 파종 10 후에 수확한 것에 비해 20일 후와 30일 후에 벼를 수확한 경우에 월동 전 분얼수는 평균 19 및 40% 감소하였다. 월동률은 평균 13 및 19% 감소하였으며, 건물수량은 평균 8 및 19% 감소하였다. 벼 입모중 이탈리안 라이그라스 파종 재배시험에서 출수기는 매년 다르게 나타났으며, 봄철 IRG 수확 시 초장은 차이가 없는 것으로 나타났다. 이상의 결과를 종합해볼 때, 논에서 입모중 파종으로 이탈리안 라이그라스를 재배할 경우, 이탈리안 라이그라스 '코윈어리' 품종은 파종 후 벼 수확시기를 가능한 빨리 하는 것이 조사료 생산성을 높이는 방법이라고 판단된다.
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.
