In vitro control of post-harvest fruit rot fungi by some plant essential oil components.

Ippolito Camele,Gian Luigi Rana,Luciana Altieri,Emilia Mancini,Laura De Martino,Vincenzo De Feo

doi:10.3390/ijms13022290

Ippolito Camele, Gian Luigi Rana + Show 4 more

Open Access

https://doi.org/10.3390/ijms13022290

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Abstract

Eight substances that are main components of the essential oils from three Mediterranean aromatic plants (Verbena officinalis, Thymus vulgaris and Origanum vulgare), previously found active against some phytopathogenic Fungi and Stramenopila, have been tested in vitro against five etiological agents of post-harvest fruit decay, Botrytis cinerea, Penicillium italicum, P. expansum, Phytophthora citrophthora and Rhizopus stolonifer. The tested compounds were β-fellandrene, β-pinene, camphene, carvacrol, citral, o-cymene, γ-terpinene and thymol. Citral exhibited a fungicidal action against P. citrophthora; carvacrol and thymol showed a fungistatic activity against P. citrophthora and R. stolonifer. Citral and carvacrol at 250 ppm, and thymol at 150 and 250 ppm stopped the growth of B. cinerea. Moreover, thymol showed fungistatic and fungicidal action against P. italicum. Finally, the mycelium growth of P. expansum was inhibited in the presence of 250 ppm of thymol and carvacrol. These results represent an important step toward the goal to use some essential oils or their components as natural preservatives for fruits and foodstuffs, due to their safety for consumer healthy and positive effect on shelf life extension of agricultural fresh products.

Highlights

The most important plant pathogens, i.e., fungi (s.l.), bacteria, phytoplasmas and viruses, can cause considerable economic damages to plant products
Our results show that some of the plant essential oils (PEOs) constituents, even if used at very low concentrations, exhibited in vitro a fungistatic and/or, in some instances, a fungicidal action against the tested organisms and, could be employed to control food-stuff decaying agents
Bary) Whetzel, used as its anamorph Botrytis cinerea Pers., isolate number 234 from grapevine; Penicillium italicum Wehrner, isolate number 333 from orange, Penicillium expansum Link, isolate number 335 from apple and Rhizopus stolonifer (Ehrenb.) Vuill., isolate number 238 from orange, were employed as basic 7-10-day-old colonies which were grown on potato dextrose agar (PDA) for P. italicum, P. expansum, B. fuckeliana, and R. stolonifer and on corn meal agar (CMA), in the case of P. citrophthora

Summary

Introduction

The most important plant pathogens, i.e., fungi (s.l.), bacteria, phytoplasmas and viruses, can cause considerable economic damages to plant products. Various attempts have been accomplished to prevent, control, or eradicate plant diseases, and development of synthetic fungicides was investigated [2] These pesticides are known to be highly effective in controlling various postharvest diseases of vegetables and fruits. Effective, their continued or repeated applications may disrupt equilibrium of ecosystems, leading to dramatic disease outbreaks, widespread development of pathogens resistant to one or more chemicals, toxicity to non-target organisms and environmental problems [2]. Their continued or repeated applications may disrupt equilibrium of ecosystems, leading to dramatic disease outbreaks, widespread development of pathogens resistant to one or more chemicals, toxicity to non-target organisms and environmental problems [2] Sometimes, they accumulate in the food chain as residues above safe limits [3]. It seemed opportune to assay the in vitro fungicidal activity of the above mentioned PEO main components against five fungi (s.l.) well known as postharvest fruit decaying agents

Results and Discussion

Fungal and Stramenopilus Isolates

In Vitro Tests

Evaluation of Fungicidal Effect of Some PEO Components

Conclusions