Effects of Supplemental Lighting of High Pressure Sodium and Lighting Emitting Plasma on Growth and Productivity of Paprika during Low Radiation Period of Winter Season

摘要

This research was carried out to investigate the effect of supplemental lighting on stable productivity of paprika (Capsicum annuum L.) during low radiation period of winter season. The supplemental lighting sources used in this research were high pressure sodium (HPS) and lighting emitting plasma (LEP). Photosynthetic photon flux density (PPFD) emitted from both lamps decreased as vertical distance from lamp increased. The PPFD of LEP lamps were twice more than that of the HPS lamp per unit distance, but the rate of decreased PPFD of the LEP per unit distance was higher than that of HPS lamp. And different degrees of PPFD between HPS and LEP lamps by horizontal distance had a smaller degree of difference than by vertical distance at the 100 cm awaypoint. As daily average PPFD measured at the top of the plant under the supplemental lighting during January, the supplemental lighting significantly increased radiation. Radiation of HPS and LEP lighting was 137% and 315% higher than control (without supplemental lighting = sunlight). Air temperature in the top of the plant was not significant different among treatments. HPS and LEP lighting had no effect on increase of flower settings. Leaf length and width with LEP lighting was the longest, photosynthetic was higher than those of other treatments. Supplemental lighting treatments significant increased fruit length and diameter. Especially LEP lighting treatment had a greater effect on fruit length and diameter. In conclusion, LEP lighting treatmentduring low radiation period greatly affected growth and production of paprika. Further research will be required for the suitable application of LEP lighting in paprika production.