Abstract:
The relative efficacies of three chemically different nano-silver (NS) formulations were evaluated for
their potential to extend the vase life of short-lived cut Acacia holosericea foliage. The novel proprietary
formulations were neutral NS, acidic NS and ionic NS. They were characterised in terms of particle size,
pH value, colour and odour. The NS treatments were applied as vase (lower concentrations) or pulse
(higher concentrations) solutions. Among the treatments compared, neutral NS as a 4 mg L−1 vase solu tion or as a 40 mg L−1 24 h pulse treatment and acidic NS as a 0.5 mg L−1 vase solution or as a 5 mg L−1 24 h
pulse treatment significantly (P ≤ 0.05) extended the vase life of A. holosericea. Vase life extensions over
the deionised water (DI) controls were associated with better maintenance of relative fresh weight and
vase water uptake, suppression of bacterial growth in the vase water and stem-end, and delaying stem
blockage. In contrast, ionic-NS applied as a 0.5 or 1 mg L−1 vase solution treatment or as a 5 or 10 mg L−1
pulse treatment caused severe phytotoxicity to cut A. holosericea stems. The results suggest that NS treat ments, especially neutral NS and acidic NS pulse treatments, could be a potential postharvest technology
for commercial application to cut A. holosericea.
