Framework for risk assessment of ‘ Candidatus Phytoplasma solani’ associated diseases outbreaks in agroecosystems in Serbia

Diseases associated with ‘ Candidatus Phytoplasma solani’ (‘ Ca . P. solani’) are of great economic importance, causing severe damage on a wide range of crops. Polyphagous insect vectors and wild plants acting as natural reservoir both play a major role in the epidemiology of phytoplasmas directly determining their transmission and persistence in agroecosystems. This is especially the case for stolbur phytoplasma diseases induced by ‘ Ca. P. solani’ a pathogen native to Europe and with a plethora of natural reservoir plants and insect vectors, some being host specific and some being generalists. Fluctuating market demands shape farming in Serbia, often limiting production to narrow or repetitive crop rotation, providing favorable conditions for continuous re-appearance of stolbur phytoplasma epidemics. Our aim was to generate scenarios in which relevant biological factors (e.g. susceptibility of crops, natural reservoirs of phytoplasma, insect vectors and their host preferences), may threat crop fields by triggering re-emergence of stolbur epidemics. Our specific objective was to assess the potential risks and to define the best management practices to cope with disease outbreaks. The first step was building an easy-to-follow online free Compendium for farmers with the list of: a) all validated host plants for stolbur phytoplasma, including both cultivated and wild plants and, b) all known insect vectors and their hosts. The Compendium also serves as a platform for a risk assessment framework integrated with a decision-making scheme that proposes different options for land use architecture and crop allocation at diverse temporal and spatial scales.