Economical light that suitable for plant production is the most necessary to promote stable operation at plant factories, because the light is basic material for growth and accounts for most of the electricity consumption on the plant factory. Recently, various LED light become widely used also be cheaper, they expected to employ substitute for conventional growth light in plant factory. While some growth LED light have developed by using red and blue LED on the wavelength in chlorophyll-sensitive, physiological response from various plant caused by specific light is not predictable through growing. We found different growth property among the lettuce plants grown with 8 light sources which equally regulated PPF in initial condition. Additionally, such changes in light-receiving posture of plants consequently would cause the changes in own effectively-receiving light in each experimental plot. Certainly, LED lights could improve the management of plant factory as growth-promotion and power-saving, it is necessary to be adequately-tested the physiological impact of specific light to each species or cultivars.
In agriculture, particularly wet rice cultivation, light pollution caused by exterior illumination at night interferes with dark periods and results in delayed flowering (heading). Therefore, five methods were introduced as a preventing technique of light pollution. (1)shading band with lights, (2)lights switched off during the period, (3)changing breeds or crop of products, (4)selecting the wavelength of lights, (5)control of luminescence. In the future, it is important that exterior illumination which prevents light pollution is proposed, even when irradiated with leak lights, to ensure a safe light environment for people.
This paper describes our previous studies on the kinetic phenomena of sugar metabolism by plant cells suspended in liquid culture media using an infrared spectroscopic measurement that could be a non-destructive, chemical-free, simple, and rapid method. We developed the simultaneous determination method of the metabolites in the liquid culture media suspending plant cells by analyzing the infrared spectroscopic characteristics, and gave the overview of the sugar metabolic kinetics based on the time course information of the metabolites contents determined by the infrared spectroscopic method. In particular, we focus our attention on the kinetic sugar uptake phenomena by suspension plant cells from the liquid culture media.
Measurement using light, for example, spectroscopy, is rapid, low cost and easy for maintenance of the instrument, and used for diagnosis of agricultural crops. Visible-near infrared method has been used non-destructively measuring color of leaf and near infrared method measuring fruit quality for practical use, respectively. On the other hand, infrared spectrophotometers have also evolved fourier transformation type. Therefore, ultraviolet, visible, near-infrared and infrared spectroscopy method is mainly described. Moreover, nitrate ions determination using light was also focused for mainly vegetables.