Derris elliptica leaf extract extends vase life of gerbera by suppressing bacterial growth and modulating oxidative stress

Abstract

Gerbera is a high-value cut flower whose commercial longevity is frequently compromised by microbial-induced vascular occlusion and oxidative stress-driven senescence. This study evaluated the efficacy of Derris elliptica leaf extract as a natural, eco-friendly biopreservative for extending the vase life of cut gerberas. Results demonstrated that D. elliptica extract significantly improved postharvest performance in a dose-dependent manner, with 175 mg L-1 identified as the optimal concentration. At this level, vase life was extended to 13.57 days, nearly double that of the distilled water control (6.93 days). The extract effectively suppressed microbial proliferation in the vase solution, maintaining a low optical density (0.15) compared to the control (0.72) at day 10. This reduction in bacterial load preserved xylem hydraulic conductivity, resulting in improved water balance, as reflected by relative fresh weight values exceeding 100%. Furthermore, the 175 mg L-1 treatment significantly alleviated oxidative damage by reducing malondialdehyde content and electrolyte leakage. This was associated with enhanced antioxidant defense along with higher total phenolic and flavonoid contents (2.6-4.7-fold over the control). However, higher concentrations (200–250 mg L-1) led to a decline in physiological performance, suggesting an optimal threshold at 175 mg L-1. Derris elliptica extract extended vase life through dual mechanisms involving microbial suppression and oxidative stress regulation.