Editorial: New trends in integrated plant disease management

Climate change has drawn the attention not only of scientists but of politicians and societies worldwide. The aim of this paper is to present a method for selecting research studies on climate change, waste management and the role of microbes in the recycling of organic matter in soil that analyze the role of organic agriculture as the main connection between agricultural losses and climate change. VOSviewer version 1.6.18 free software tool was used in this study in order to achieve the bibliometric and mapping approach for studies on the effects of climate change in terms of soil recycled organic matter and microbe interaction. Scopus database (accessed 29 September 2022) indexed a total of 1,245,809 bibliographic items classified into paradigms. The presented documents were downloaded from Scopus as graph-based maps and as distance-based maps in order to reflect the strength of the relation between the items. Climate change includes changes in soil and soil microorganisms as affected by natural climate variations and local weather, which have beneficial or negative effects on soil organic matter. From the examination of the selected papers, it was concluded that climate change and changing precipitation patterns are having an impact on microorganisms, particularly bacterial groups, and thus ecosystem function.

The antifungal activity of olive oil mill wastewater (olive OMW) on Botrytis cinerea Pers was investigated. The effect of sterilized, filtered and non sterilized olive OMW was tested in vitro: a) on mycelium growth of B. cinerea on PDA agar plates and b) on strawberry and pepper fruits infected with the pathogen. The results show that the filter sterilized olive OMW inhibits the growth of B. cinerea mycelium in vitro probably due to the activity of the phenolic compounds contained on olive OMW. Furthermore, olive OMW significantly decreased fungus mold formation on the tested fruits.

The antifungal activity of olive oil mill wastewater (olive OMW) was investigated. The effect of sterilized and filter sterilized olive OMW was tested in vitro: a) on mycelium growth of Fusarium oxysporum f.sp. lycopersici, Pythium spp., Sclerotinia sclerotiorum and Verticillium dahliae on PDA agar plates; b) on sporulation of Penicillium italicum and P. digitatum and Botrytis cinerea on infested with the pathogens fruit and-vegetables (oranges and red horn peppers) and c) on planta, tomato plants infested with the fungus F. oxysporum f.sp. lycopersici. The results show that the filter sterilized olive OMW inhibits the mycelium growth of all tested fungi in vitro, probably due to phenolic compounds which are contained in olive OMW. Furthermore, olive OMW decreased fungi spores' number on infested fruits-vegetables and acted positively on tomato plants fresh weights, infested with the soil borne pathogen F. oxysporum f.sp. lycopersici.

The chemical composition of the essential oils from Origanum vulgare and O. onites L., was analysed by GC/MSD. Carvacrol and thymol were indentified as main constituents and all tested essential oils, carvacrol and thymol presented enhanced antifungal activities in vitro assays. Moreover, the antifungal assays showed that O. vulgare essential oil collected from the mountain Olympus from “Leptokaria” region, rich in thymol, completely inhibited mycelia growth of soil-borne plant pathogens.

Pseudomonas oryzihabitans, a bacterium associated with the entomopathogenic nematode Steinernema abbasi, was evaluated for its potential to colonise roots and thereby control a field population of root-knot nematodes. Immunological techniques were developed to detect root colonisation of P. oryzihabitans on tomato roots using a specific polyclonal antibody raised against vegetative bacterial cells. In vitro, bacterial cell filtrates were also shown significantly to inhibit juveniles hatching. In a glasshouse pot experiment, there were 22 and 82% fewer females in roots of plants treated with suspensions containing 103 and 106 cells ml−1 of P. oryzihabitans, respectively. In addition, there were significantly fewer egg masses produced; however, the numbers of eggs per egg mass did not differ significantly. The relationship between root colonisation and nematode control is discussed.