Fungal diseases seriously affect agricultural production and the food industry. Crop protection is usually achieved by synthetic fungicides, therefore more sustainable and innovative technologies are increasingly required. The atmospheric pressure low-temperature plasma is a novel suitable measure. We report on the effect of plasma treatment on phytopathogenic fungi causing quantitative and qualitative losses of products both in the field and postharvest. We focus our attention on thein vitrodirect inhibitory effect of non-contact Surface Dielectric Barrier Discharge on conidia germination ofBotrytis cinerea,Monilinia fructicola,Aspergillus carbonariusandAlternaria alternata. A few minutes of treatment was required to completely inactivate the fungi on an artificial medium. Morphological analysis of spores by Scanning Electron Microscopy suggests that the main mechanism is plasma etching due to Reactive Oxygen Species or UV radiation. Spectroscopic analysis of plasma generated in humid air gives the hint that the rotational temperature of gas should not play a relevant role being very close to room temperature.In vivoexperiments on artificially inoculated cherry fruits demonstrated that inactivation of fungal spores by the direct inhibitory effect of plasma extend their shelf life. Pre-treatment of fruits before inoculation improve the resistance to infections maybe by activating defense responses in plant tissues.

Monilinia spp. are responsible for brown rot decay of stone and pome fruit in the field as well as in postharvest. Monilinia laxa and M. fructigena are considered indigenous to Europe, while M. fructicola is a quarantine pathogen in the European and Mediterranean Plant Protection Organization area included in the A2 List. In Italy, it was first reported in 2009 in Piedmont (northern Italy) and rapidly spread to central Italy. We carried out a monitoring program on the occurrence of Monilinia spp. in southern Italy and a comparative characterization of the three main fungal pathogens. Molecular assays based on direct polymerase chain reaction (PCR) and real-time quantitative PCR for molecular identification of Monilinia spp. from rotted fruit were set up, validated, and applied in a monitoring program. Of the tested 519 isolates from 26 orchards, 388 (74.8%) were identified as M. fructicola, 118 (22.7%) as M. laxa, 10 (1.9%) as M. fructigena, and 3 (0.6%) were M. polystroma. M. fructicola colonies grew faster and had a higher optimal temperature for growth (26°C) than M. laxa (23°C) and M. fructigena (20°C). No relevant difference in virulence could be observed on artificially inoculated apricot, cherry, and peach fruit. The fungal species showed different responses to fungicides, because M. fructicola was more sensitive than M. laxa, especially to cyflufenamid, and M. fructigena revealed a lower sensitivity to succinate dehydrogenase inhibitors (boscalid, fluopyram, and fluxapyroxad) and quinone outside inhibitors (mandestrobin). In summary, the two species M. fructicola and M. polystroma were first detected in southern Italy where M. fructicola has largely displaced the two indigenous pathogens M. laxa and M. fructigena; the relative proportions of the three pathogens in orchards should be considered when defining the management of brown rot of stone fruit due to differences in their responses to fungicides.