The Antifungal Effect of Gaseous Ozone on Lasiodiplodia theobromae Causing Stem-End Rot in ‘Keitt’ Mangoes

Abstract

This study evaluated the antifungal activity of ozone (O3) against stem-end rot of mango fruit (cv. Keitt). Mango fruit were exposed to gaseous ozone (0.25 mg/L) for 24 or 36 h during cold storage, and control fruit were untreated. Experimental fruit were stored at 90% relative humidity and 10 ± 0.5 °C for three weeks and ripened at ambient temperature for one week. Ozone treatment (24 h) inhibited the mycelial growth of Lasiodiplodia theobromae by 60.35%. At day twenty-eight of storage, fruit treated with O3 for 36 h had low mass loss (%) and high firmness compared to the untreated control fruit. Treating mango fruit with O3 (36 h) maintained the color and concentration of total flavonoids throughout the storage time. At the end of storage, peroxidase activity under the O3 24 h treatment was significantly higher (0.91 U min−1 g−1 DM) compared to O3 (36 h) and control, which, respectively, had 0.80 U min−1 g−1 DM and 0.78 U min−1 g−1 DM. Gaseous ozone for 24 h is recommended as a cost-effective treatment for controlling stem-end rot. These findings suggest that gaseous ozone effectively controlled stem-end rot and enhanced the postharvest quality of mango fruit.

Could alien invasive species be a solution to postharvest losses of fresh produce?

“…The stem-end-rot causing Lasiodiplodia theobromae and anthracnose causing Colletotrichum gloeosporioides are some of the prevalent postharvest pathogens. They are controlled using antimicrobial and biofungicidal treatments such as gaseous ozone (Bambalele et al, 2023) and edible coatings (Kubheka et al, 2020;Nkanzela et al, 2021). Enzymatic browning is one of the major quality issues during postharvest.…”