Improving “color rendering” of LED lighting for the growth of lettuce

• Published in: Scientific reports Vol. 7; no. 1; p. 45944
• Main Authors: Han, Tao, Vaganov, Vitaliy, Cao, Shixiu, Li, Qiang, Ling, Lili, Cheng, Xiaoyao, Peng, Lingling, Zhang, Congzhi, Yakovlev, Alexey N., Zhong, Yang, Tu, Mingjing
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03-04-2017; Nature Publishing Group
• Subjects: 631/449/2686; 639/624/1020/1089; Biomass; Color; Correlation coefficient; Growth rate; Humanities and Social Sciences; Irradiation; Lactuca - growth & development; Lactuca - radiation effects; Leaf area; Leaves; Lettuce; Light; Light emitting diodes; Lighting; Lighting - instrumentation; multidisciplinary; Photoperiod; Photosynthesis - radiation effects; Plant biomass; Plant growth; Plant Leaves - growth & development; Plant Leaves - radiation effects; Radiation; Science; Semiconductors; Time Factors; Vegetables
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep45944

Light plays a vital role on the growth and development of plant. On the base of white light with high color rendering to the benefit of human survival and life, we proposed to improve “color rendering” of LED lighting for accelerating the growth of lettuce. Seven spectral LED lights were adopted to irradiate the lettuces under 150 μmol·m
−2
·s
−1
for a 16 hd
−1
photoperiod. The leaf area and number profiles, plant biomass, and photosynthetic rate under the as-prepared LED light treatments were investigated. We let the absorption spectrum of fresh leaf be the emission spectrum of ideal light and then evaluate the “color rendering” of as-prepared LED lights by the Pearson product-moment correlation coefficient and CIE chromaticity coordinates. Under the irradiation of red-yellow-blue light with high correlation coefficient of 0.587, the dry weights and leaf growth rate are 2–3 times as high as the sharp red-blue light. The optimized LED light for lettuce growth can be presumed to be limited to the angle (about 75°) between the vectors passed through the ideal light in the CIE chromaticity coordinates. These findings open up a new idea to assess and find the optimized LED light for plant growth.