Development of LED Light Environment Control System and its Application to the Study of Physiological Responses in vitro and during ex vitro Acclimatization of Limonium

• Main Authors: Jin-Nan Chen, 陳金男
• Other Authors: 陳世銘
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/70555473662918752809

碩士 === 國立臺灣大學 === 生物產業機電工程學研究所 === 93 === Light-Emitting Diodes (LED) are widely used every walk of life recently such as artificial light for plants. There are many advantages like specified wavelength, higher electric-light transformation performance and lower heat generation. The study is aimed to develop a light environment control system (LECS) using red and blue light LED’s as a light source. A light simulation and control program was developed to integrate and control the LECS system using LabVIEW software. Using the program, the LED-array can be arranged at random to define different aspects of light quality. Individual setting the light intensity of red and blue LED’s can also change the light quality and intensity simultaneously. The program can monitor the control photoperiods when applying to plant cultivation. Therefore, light quality, light intensity and photoperiod can be controlled flexibly when LECS system is used. The red LED module and blue LED module can individually provide a light intensity of 150 mmol m-2 s-1, and the red/blue LED mixed module can provide about 80 mmol m-2 s-1 for red light, and about 50 mmol m-2 s-1 for blue light at 10 cm height. Using the developed LECS system, four settings of light quality (pure red light, pure blue light, R/B ratio = 1:2 and R/B ratio = 2:1) were applied to tissue culture experiments of Limonium. The results show that: leaves developed under pure blue light become thiner, whiter and lower in chlorophyll content. When the proportion of red light is increasing, leaves are more close to those developed under tube fluorescent light. There is no significant difference in wet and dry weight among all the treatments. All the samples can be recovered to a normal growth when tube fluorescent light is provided during ex vitro acclimatization. The light environment control system developed in this study has potential applications to tissue culture production and the study of light quality effects on morphogenesis and physiology of plants.