Intumescence incidence and growth of ‘Sinhong’ chili pepper seedlings under different light qualities

Abstract

Intumescence is a physiological disorder, in which epidermal cells of leaves and stems enlarge and occur mainly in solanaceous crops. Intumescence not only impairs the physiological processes of plants but also negatively affects the aesthetic quality of the crop. Intumescence research is mainly conducted on tomatoes, the disorder has been reported to be observed under a lacking blue or ultraviolet (UV) spectrum. In addition, far-red light has been reported to diminish the incidence of intumescence. But the intumescence inhibition effect of the light quality is different between crops. Pepper (Capsicum annuum L.) is also a solanaceous crop like tomatoes. Korean chili pepper seedlings are exported to various countries such as Japan and China. Therefore, this study was conducted to investigate the effects of different light qualities on the incidence of intumescence in chili pepper seedlings. Pepper seedlings are placed in plant factories with artificial lighting (PFAL) with light treatment set as monochromatic red light (R), green (G), and blue (B), mixed R, G, B (RG, GB, RB = 5:5), W (RGB = 5:2:3, as the control), RB+UV (RB+UV-A 0.4 μW m-2), and RB+Fr (R:B:Far-red = 4:4:2). All treatments were provided 12 h a day with a light intensity of 110±5 μmol m-2 s-1. As a result, the highest intumescence incidence appeared in RG light. The results of this study can be used as basic research data for the inhibition of the intumescence incidence in pepper. © 2025 International Society for Horticultural Science. All rights reserved.