Control of Postharvest Fungal Rots on Grapes Using Essential Oil of Foeniculum vulgare Mill.

Abstract

Fungal rots, caused by Botrytis cinerea and Colletotrichum acutatum, are the main causes of postharvest decay of table grapes in Brazil. The aim of this study was to assess the chemical composition and the fungicidal effect of Foeniculum vulgare essential oil in vitro, on mycelial growth (contact and volatile phase) and conidia germination, and in vivo on postharvest grapes against both fungi. The major compounds found in F. vulgare essential oil were trans-anethole (79.14%), fenchone (11.94%) and estragole (5.76%). The mycelial growth (contact phase) and conidia germination of B. cinerea were inhibited completely at concentrations of 50 and 100 ppm (µL mL -1 ), respectively. For C. acutatum, mycelial growth (contact phase) and conidia germination were inhibited completely at concentrations of 100 and 200 ppm, respectively. The volatile phase had a fungistatic effect on mycelial growth of both fungi at different concentrations tested, and the pure essential oil (100%) presented fungicidal effect against B. cinerea. In vivo tests were carried out using grapes of Vitis spp. cv. "Isabella" and the concentrations of essential oil tested were efficient, reducing the incidence of disease caused by B. cinerea and C. acutatum at postharvest, both in preventive and curative treatment. The concentration 200 ppm completely inhibited the incidence of both fungi. In conclusion, F. vulgare essential oil presented fungicidal action against postharvest fungal rots on grapes.

Alternative control of grape rots by essential oils of two Eucalyptus species

“…To assess fungicidal action of the volatile phase of EOs on the MG of fungi the methodology adopted by Pedrotti et al . was utilized.…”

“…The antifungal properties of EOs were assessed for its contact and volatile phase effects towards MG of phytopathogens. Contact phase effect of EOs was tested according to Pedrotti et al 25 EOs concentrations ranged between 0.1 to 7 μL mL −1 . EO was emulsified with Tween 20 (1: 1) and added to the culture medium PDA.…”

“…To assess fungicidal action of the volatile phase of EOs on the MG of fungi the methodology adopted by Pedrotti et al 25 was utilized. Agar disks of 5 mm (Ø) colonized by B. cinerea or C. acutatum mycelium were placed in the centre of petri dishes containing PDA medium.…”

“…Antifungal activity of EOs on conidia germination was tested according to Pedrotti et al 25 Briefly, B. cinerea and C. acutatum conidia were harvested from 14-day-old fungal colonies grown in PDA at 25 ∘ C under 12 h photoperiod. Then, 5 mL of sterile water was added to a petri dish culture.…”

In vitro and in vivo antifungal activity of Cuminum cyminum essential oil against Aspergillus aculeatus causing bunch rot of postharvest grapes

“…C. cyminum essential oil showing strong inhibition percentage in in vitro experiments were selected for conidia germination experiments in accordance with the procedure described by Pedrotti et al [26]. Pure volatile compounds including cumin aldehyde and α-terpinen-7-al were also tested to determine their effect against conidia germination of A. aculeatus.…”