Experimental Study of Effects of Artificial Light Sources on the Coloring of Fig Fruits

Abstract

In the green house cultivation to diversify harvest times, supplemental lighting systems are necessary to compensate the lack of sun light. Besides, artificial light sources of the system for fig fruits are needed to accelerate the coloring.
Paying attention that matured figs have reddish violet colors in general, using harvested figs, colors and quantities of pigments (anthocyanin) on their surfaces are investigated. On cultivating processes, figs are radiated by artificial light sources with different spectral distributions.
By studying comparisons between spectral distribution of light sources and experimental results, it is confirmed that generations of pelargonidin and cyanidin in anthocyanin are related to the coloring, and that two types of fluorescent lamps are effective to generate pigments on surfaces of figs. One type is for use of coping machine, and the other is with three-band phosphors.