Growth and Ground Coverage of Ophiopogon japonicus 'Nanus' under Different Shade Conditions

Demand for dwarf mondo grass (DMG; Ophiopogon japonicus 'Nanus') as an ornamental garden plant is expected to grow in the future. The purpose of this study was to investigate the levels of shade tolerance and ground cover by growing DMG under a variety of shade conditions for 18 months (May 2015~October 2016). DMG plants grown in bare ground for 3 years in Jangheung-gun, Jeonnam were used for testing. In an experimental site created in Naju city in Jeonnam, the DMG was planted in planters ($70cm{\times}70cm{\times}24cm$) and covered with a shading curtain to block natural light. Shaded conditions were then arranged under different levels of shade (0%, 55% and 75%). When the plants were grown, growth (leaf size, the number of leaves, fresh weight and dry weight) and ground coverage of DMG were analyzed. According to the results, DMG growth in terms of leaf size and the number of leaves was statistically higher under zero shade (full sunlight), when compared to other shaded conditions. DMG's fresh and dry weights were significantly greater under 0% and 55% shade, compared to those under 75% shade. The degrees of shade tolerance required for normal growth of DMG were found in the range of 0~50%, meaning that more than 50% shade may decrease plant growth. There were no statistical differences in ground coverage rates of DMG under different levels of shade. When 220 tillers were planted per $1m^2$ of plot, up to 80% of the area was covered by DMG after 18 months. Since DMG requires nutrient-rich soil to grow, sufficient nitrogen fertilizers are proposed to accelerate the ground cover of DMG. As DMG remained alive over the winter in the experiments, this study also suggests that DMG can be planted in the southern temperate region.

차광처리에 따른 애기소엽맥문동의 생장과 피복에 관한 연구

정원소재로서 수요가 늘어날 것으로 예상되는 애기소엽맥문동(Ophiopogon japonicus 'Nanus')을 대상으로 18개월(2015년 5월~2016년 10월)간 차광생육실험을 실시해 내음성 범위와 피복정도를 알아보았다. 전남 장흥군 노지에 3년간 재배된 애기소엽맥문동을 공시재료로 이용했다. 전남 나주시의 실험장에서 식재상자($70cm{\times}70cm{\times}24cm$)에 애기소엽맥문동을 심고 차광막을 덮어 자연광을 차단했는데 차광처리 수준은 무차광(0%), 55%, 75%이었다. 차광처리구별 생장량(엽장, 엽수, 생중량 건중량)과 지표면 피복률을 조사했다. 애기소엽맥문동의 엽장 엽수는 무차광(0%)이 다른 처리구보다 통계적으로 높았다. 생중량 건중량은 무차광(0%) 차광처리 55%가 차광처리 75%보다 유의적으로 많았다. 애기소엽맥문동이 정상적으로 생육가능한 내음성 범위는 차광률 0~50%정도며, 50%이상의 자연광이 차단되면 생장량이 감소하는 것으로 판단된다. 차광처리구별 피복률은 통계적 차이를 보이지 않았다. 애기소엽맥문동을 $1m^2$당 220분얼을 심었는데 18개월 후에는 지표면 80%까지 덮었다. 애기소엽맥문동은 비옥한 토양에서 생육이 적합해 조기 피복을 위해선 충분한 질소비료 시비가 필요하다. 본 실험장에서 애기소엽맥문동은 동해를 입지 않아 온대 남부지역까지 식재 가능할 것으로 보인다.