Effect of Autoclaved Lightweight Concrete(ALC) on Growth and Flowering in Three Species of Cymbidium and Doritaenopsis Plants as a Potting Medium
난 식재용토 대체용으로 경량기포 콘크리트 부산물(Autoclaved Lightweight Concrete; ALC)을 여러 난과식물의 재배에 이용한 결과 동양란 심비디움 ‘Gengi’의 생육은 경량콘크리트 부산물인 ALC에서 가장 좋았으며 특히 화경 추대는 다른 기존의 식재용토에 비해 월등히 양호하였다. 엽록소 함량은 하이드로볼 처리구에서 높았고, 엽록소형광(Fv/Fm)은 ALC에서 가장 낮았다. 서양란 심비디움 ‘Majolica’의 생육은 휴가토에서 가장 좋았으나 화경수는 휴가토와 ALC에서 많았다. 따라서 ALC는 심비디움의 화경 형성에 효과적임을 알 수 있었다. 반면 착생란인 호접란의 생육은 원예용 혼합 상토에서 가장 좋았다. 동양란과 서양란 심비디움에서 화경 형성에 ALC가 좋았던 것과 달리 호접란은 바크 식재구에서 화경이 가장 많이 형성되었다. 엽록소 함량 역시 바크 처리구에서 높았고, Fv/Fm은 ALC에서 자란 심비디움에서 높았고 착생란인 호접란은 보수력이 좋은 상토 처리구에서 생육이 가장 좋은 것을 알 수 있었다. 본 연구결과 건축부산물인 ALC는 지생란인 동양란과 서양란 심비디움의 생육과 화경 발달에 효과적이었으며 휴가토, 녹소토, 혹은 하이드로볼 대체용으로 이용 가능성이 높을 것으로 생각된다.
Autoclaved Lightweight Concrete (ALC), which is produced by the fragmentation of wastes by construction, has a particulate structure and contains nutrients in forms that are readily available for plant uptake. To investigate the potential use of ALC as an orchid potting medium, two kinds of Cymbidium [C. hybrid ‘Gengi’, C. ‘Majolica’] and Doritaenopsis glenyl ‘Labios’ were grown in various commercial horticultural potting medium including ALC. The growth of two Cymbidium species was enhanced significantly upon substitution of ALC or bark by increasing fresh weight and the number of leaves and pseudo bulbs in C. ‘Gengi’, and increasing fresh weight in C. ‘Majolica’. The emergence rate and the number of flower stems were significantly enhanced in the plants of C. ‘Gengi’ grown in ALC and Hugato, and in C. ‘Majolica’ grown in ALC and bark. However the growth and flowering of Dtps. glenyl ‘Labios’ plant was suppressed in ALC irrelevant with the particle size of ALC. Although two species of Cymbidium growth was enhanced in ALC, it didn’t affect chlorophyll and carotenoid content. In C. ‘Gengi’ and C. ‘Majolica’, chlorophyll fluorescence (Fv/Fm) was the highest in the plants grown in ALC, but the lowest in Dtps. glenyl ‘Labios’.
By SEM, the surface of ALC has more space than Hydroball, and softer than Hugato. It reveals that ALC is able to absorb more water than those commercialized potting medium, and it may resulted in better growth in terrestrial Cymbidium, but not enough in Dtps. glenyl ‘Labios’. Our results showed that ALC has the potential for improving plant growth and flowering in terrestrial Cymbidium by improving photosynthesis.