본 연구의 목적은 폐쇄형 식물생산시스템에서 세가지 혼합 LED와 형광등에서 자란 적치마 상추의 생육과 광 이용효율을 비교하는 것이다. 18일간 육묘한 적치마상추 묘를 적색(R, 655nm), 청색(B, 456nm), 녹색(G, 515nm), 백색(W, 456nm + 558nm)의 혼합 LED(R:B=8:2, R:W:B =8:1:1, R:G:B=8:1:1)와 형광등이 설치된 폐쇄형 식물생산시스템에 정식하였다. 형광등에서 자란 상추는 모든 LED 처리에 비해 유의적으로 높은 엽형지수를 보였다. 지상부와 지하부 생육에서 LED 처리간 유의적 차이를 보이지 않았으나, 모든 LED 처리가 형광등에 비해 약 34% 지상부 생체중의 증가를 유도시켰다. 한편, 정식 후 4주차에 형광등의 총 소비 전력은 145kW인 반면, LED 처리구들에서 형광등의 약 1/3배인 54kW를 나타냈다. LED 처리구들의 건물중에 대비한 광 이용 효율은 약 34mg/W였으며, 이는 형광등 보다 약 3.5배 높은 값이었다. 결론적으로, 본 연구는 식물 생산 시스템에서 적절한 조합의 LED 조사는 형광등에 비해 상추 생장을 증진시킬 수 있으며 추가적으로 에너지 절감을 통해 광 이용효율도 극대화 할 수 있음을 보여주었다.

The objective of this study was to compare the growth and light use efficiency of red leaf lettuce grown under three types of combined light-emitting diodes (LEDs) and fluorescent lamps (FL) in a closed-type plant production system. The eighteen days-old lettuce seedlings of red leaf lettuce (Lactuca sativa L., ‘Jeokchima’) were transplanted to the closetype plant production system equipped with three types of combined LEDs with red (R, 655 nm), blue (B, 456 nm), green (G, 515 nm), and white (W, 456 nm + 558 nm) (R:B=8:2, R:W:B=8:1:1, R:G:B=8:1:1) and FL. The seedlings were grown under normal growth conditions (20oC, 181±4 μmol·m-2·s-1, 12 h photoperiod) for four weeks. Lettuce plants grown under FL had significantly higher leaf shape index than those under all LED treatments. Although growth of shoots and roots was not show any significant difference among LED treatments, all of the LED treatments induced about 34% higher shoot fresh weight than that of the FL. On the other hands, the total power consumption of FL was 145 kW for 4 weeks, while the mean value of LED treatments was 54 kW, which was about 3 times lower value than that of the FL. The light use efficiency based on dry matter in LED treatments was about 34 mg/W and this was about 3.5 times higher energy saving value than the FL. In conclusion, this study showed that irradiation of optimal combined LEDs in closed-type plant production systems can improve the lettuce growth as well as maximize in light use efficiency through energy saving than the FL.

서 론
 재료 및 방법
  1. 식물재료 및 재배환경
  2. LED 처리
  3. 생육 특성
  4. 광 이용 효율
  5. 통계처리
 결과 및 고찰
  1. 인공광원 발열량
  2. 생육 특성
  3. 광 이용효율
 적 요
 Literature Cited

• 손기호(충북대학교 축산·원예·식품공학부 원예학전공, 생물건강소재산업화사업단, Division of Animal, Horticultural and Food Sciences, Chungbuk National University, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University) | Ki-Ho Son
• 송민정(충북대학교 축산·원예·식품공학부 원예학전공, 생물건강소재산업화사업단, Division of Animal, Horticultural and Food Sciences, Chungbuk National University, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University) | Min-Jeong Song
• 오명민(충북대학교 축산·원예·식품공학부 원예학전공, 생물건강소재산업화사업단, Division of Animal, Horticultural and Food Sciences, Chungbuk National University, Brain Korea 21 Center for Bio-Resource Development, Chungbuk National University) | Myung-Min Oh Corresponding author