Essential oil from ginger as a novel agent in delaying senescence of cut fronds of the fern (Davallia solida (G. Forst.) Sw.)

Rabbit's foot fern (Davallia solida (G. Forst) Sw.) is traded as cut floral greens and commonly used in orchid flower arrangements and bouquets; however, its use is limited by its relatively rapid postharvest yellowing and desiccation. This study was designed to investigate the chemical profile of the essential oil from ginger rhizome (Zingiber officinale Roscoe) and to determine the oil's effectiveness in extending the postharvest quality of rabbit's foot fern. Essential oil was extracted from ginger rhizomes by hydrodistillation. The percentage composition of major identified compounds was citral (29.91%), zingiberene (13.3%), alpha-farnesene (11.68%), 1,8-cineole (10.60%), and beta-sesquiphellandrene (6.14%). The ginger essential oil was applied in emulsion form to rabbit's foot fern fronds as a pulse (25, 50, or 100 mg L-1) or a holding solution (5, 10 and 20 mg L-1). Pulse treatments were applied for 6 h before the fronds were transferred into a holding solution containing either distilled water or essential oil of ginger. Control fronds received distilled water as both pulsing and holding solutions. Rabbit's foot fern pulsed with 25 mg L-1 essential oil and transferred into a holding solution with 5 mg L(-1 )essential oil increased frond longevity by 4.9 days and helped maintain both water uptake and visual quality. Under this treatment, fronds exhibited higher chlorophyll a and b contents, lower malondialdehyde content, and delayed loss of radical scavenging ability compared to control. Together, these results indicate that when dosed appropriately in pulsing and holding solutions, essential oil of ginger prolongs the vase life of fronds; it also enhances postharvest quality by simultaneously retarding the degradation of chlorophyll a and b, preserving DPPH scavenging activity, and lowering malondialdehyde accumulation.