Effect of light from cold cathode fluorescent lamps on tree peony (Paeonia suffruticosa) calli

Abstract

SummaryLight quality has significant effects on the growth of Paeonia suffruticosa calli in vitro. In this study, callus growth was examined under six different combinations of light of different wavelengths using cold cathode fluorescent lamps (CCFLs): 100% white (W; 410 - 730 nm); 100% red (R; 622 - 625 nm); 100% blue (B; 467 - 470 nm); 80% R plus 20% B; 70% R plus 30% B; or 60% R plus 40% B. Calli grown under regular fluorescent lamps served as the controls. Calli cultured under red light at 622 - 625 nm had the highest average fresh weight (FW; 1.2206 g per callus) and average increase in callus FW (1.1519-fold per callus), compared to calli grown under the other six light conditions. Chlorophyll concentrations per callus were highest in calli cultured under 60% R plus 40% B light. Callus physiology and biochemistry, including total soluble sugar concentrations and peroxidase activity, were higher under 100% R light than under the other six light conditions. Total soluble protein and phenolic compound concentrations were higher under 100% B light than under the other six light conditions.This study indicates that CCFLs are a more effective light source than regular fluorescent lamps for callus growth in P. suffruticosa.