Efficacy of Pelargonium graveolens essential oils against some postharvest fungal diseases of apple

Background: Postharvest diseases that occur in apples are often caused by various pathogenic fungi, causing serious economic loss. The pathogenic fungi Penicillium expansum, Rhizopus stolonifer and Botrytis cinerea are among the most common pathogens in apples. The goal of this study was to see whether Moroccan Pelargonium graveolens essential oil (PGEO) could protect apple fruits from fungal infections after they were harvested (in vitro).Methods: PGEO was characterized by GC-MS and for antifungal assessment, in vitro poisoned food (PF) and volatile activity testing (VA) were carried out.Results: The investigation revealed that PGEO was effective against the three tested phytopathogenic fungi in a dose-dependent manner and this antifungal activity increased with the volatile activity test. The MIC value was 2 µL/mL for B. cinera, and R. stolonifer, and 1 µL/mL for P. expansum. Volatile fraction stops the growth of B. cinera at 40 µL / disc (QMI = 40 µL / disc), and of P. expansum and R. stolonifer at 80 µL / disc (QMI = 80 µL / disc).Conclusion: The current findings show that Moroccan PGEO has powerful antifungal activities, suggesting that it might be used instead of synthetic fungicides to combat apple post-harvest infections.Keywords: Pelargonium graveolens; Antifungal activity; Essential oil; Poisoned food; Volatile activity test; Apple

Antifungal activity of essential oil from Santolina pectinata lag., against postharvest phytopathogenic fungi in apples

The purpose of this study was to investigate the chemical composition and antifungal activities of essential oil (EO) of Santolina pectinata aerial parts. The analysis of EO using gas chromatography (GC-FID) and gas chromatography-mass spectroscopy (GC-MS) allowed the identification of 34 components, which (Z)-heptadeca-10,16-dien-7-one was the major constituent with 28 % of the total oil. The antifungal activities of this oil in liquid and vapor-phase against three phytopathogenic fungi causing the deterioration for apples, including Botrytis cinerea, Penicillium expansum and Rhizopus stolonifer were evaluated in vitro by using the poisoned food (PF) and the volatile activity (VA) methods. The obtained results showed a significant inhibition of the studied EO inhibited significatively against the mycelial growth of all fungal strains tested (p<0.05). B. cinerea and P. expansum showed a strong sensitivity to the studied oil at all concentrations and VA assay was consistently found to be more effective than PF technique. The minimum inhibitory concentrations (MICs) of this oil were 0. 25 and 1 µL/mL against these strains when using VA and PF assays, respectively. The overall results suggest that S. pectinata EO could be used as an antifungal preservative to control post-harvest diseases of apples. The antifungal activities of S. pectinata EO from Morocco are reported for the first time