Horticultural Science and Technology 원예과학기술지 ISSN:1226-8763(Print) 2465-8588(Online)

This study was conducted to investigate the antimicrobial effect of chlorine dioxide (ClO²) on the vase life of cut rose ‘Beast’ (Rosa hybrida L.). Postharvest treatments to extend the vase life of cut roses were divided into two: holding solution treatment and pulsing solution treatment. In holding solution treatment, the cut roses were treated with preservative solutions containing tap water (TW, control), distilled water (DW), ClO² 2, 4, 6, and 8 µL･L-¹, and compared with a commercialized antimicrobial compound of 8-HQS 200 µL･L-¹. In pulsing solution treatment, cut roses were dipped into the ClO² solutions of 50, 100, 150, 200, and 250 µL･L-¹ for 60 seconds and were placed in DW. The air temperature was 18.4°C, RH 51.5%, and light (photosynthetically active radiation, PAR) 3.6 µmol･m-2･s-1 with 12 hour day length. The longest vase life of cut roses was observed in the holding solution with ClO² 4 µL･L-¹ as 13.8 days and pulsing with 200-250 µL･L-¹ as 13.5-13.7 days, where vase life were extended four days longer than TW. Whereas, the inclusion of 8-HQS 200 µL･L-¹ in vase solution resulted in phytotoxicity. The relative fresh weight and water uptake have similar tendencies. Bacteria inhibition by ClO² and 8-HQS were very effective. But bacteria at TW and DW treatments on cut flower with stem were detected in 3.7 × 105 CFU･L-¹ and 6.3 × 10⁵CFU･L-¹, respectively (without stem in DW 1.4 × 104 CFU･L-¹). The ClO² contents in holding solution of all treatments were scavenged in two-four days after treatment. This study indicated that ClO² 4 µL･L-¹ holding solution treatment and 200-250 µL･L-¹ pulsing solution treatment can be applied to extend the postharvest life of cut roses.