Effect of LED and QD-LED(Quantum Dot) Treatments on Production and Quality of Red Radish(Raphanus sativus L.) Sprout

Abstract

The purpose of this study was to investigate the effects of LED and QD-LED (Quantum Dot) irradiation on seed germination, antioxidant ability, and microbial growth, during red radish (Raphanus sativus L.) sprouts cultivation. Irradiated light was blue, red, blue + red and blue + red + far red (QD-LED) lights, and the controls were a fluorescent lamp (FL), and dark condition. Germination rate of red radish was highest in the dark condition. The plant height and fresh weight of red radish sprouts that irradiated each light for 24 hrs after 7 days growing in dark condition, did not shown significantly difference among treatments. After 24 hrs of light irradiation, cotyledon green was best in blue + red light, and the red hypocotyl was excellent in blue light and QD-LED light. DPPH and phenol contents were high in dark and blue + red light treatment, and anthocyanin content was high in blue light and QD-LED light. Total aerobic counts were similar in all treatments and did not show bactericidal effect, whereas E. coli count was lowest in QD-LED light treatment, and yeast and mold counts were lowest in FL only treatment. Results suggest that when red radish seeds were germinated in dark condition and cultivated for 7 days as sprouts, and then treated with blue light or QD-LED light for 24 hrs, the seeds produced good quality red radish sprouts with greenish cotyledon, reddish hypocotyl, high anthocyanin content, and lower level of E coli contamination.

Germination Characteristics and Seedling Growth of <italic>Pseudolysimachion nakaianum</italic> (Ohwi) T. Yamaz. Seeds According to Light Quality Type

“…In addition, Lee et al (2020) reported that the group of Veronica rotunda seedlings irradiated with red LED demonstrated outstanding initial growth, but the group irradiated with blue LED showed growth inhibition, which was attributed to the variation in initial GR at different light qualities. As each plant species exhibits a unique level of sensitivity to light quality, seed germination characteristics vary (Choi et al, 2019).…”

Effect of Red and Blue LED Ratio on Growth and Glucosinolate Contents of Watercress (Nasturtium officinale) in a Plant Factory

“…특히 광원설계는 사전 예비 실험을 통하여 최적화를 이루어야 하고, 최초 광질의 선택은 향후 파장 조건을 변경하기 힘들기 때 문에 매우 중요하다. 식물공장에서 안정적인 고품질 물냉이 생산을 위하여 양액 종류 및 양액 내 마이크로 버블을 이용한 연구 등을 보고한 바 있다 (Choi et al, 2018;Bok et al, 2019) (Choi et al, 2019)에 기반하여 본 실험에 적용하였다.] 각 광원의 비율 조합은 파장별 광합성유 효광량자속밀도(PPFD: photosynthetic photon flux density)를 기준으로 각각 R10(Red:Blue = 10:0), R9B1(Red:Blue = 9:1), R8B2(Red:Blue = 8:2), R7B3(Red:Blue = 7:3), R6B4(Red:Blue = 6:4), R1B1G1(control, Red:Blue:Green = 1:1:1) 으로 설정하였다.…”