9. Susceptibility of the plum cultivars ‘Jojo’ and ‘Togigant Plus’ to some postharvest diseases

Author: Diyana Aleksandrova, Marieta Nesheva, Nataliya Dimitrova

Abstract

Postharvest diseases cause significant losses in orchards before and after fruit harvest. The study aimes to compare the susceptibility of the plum cultivars ‘Topgigant Plus’ and ‘Jojo’ each grafted on the plum seedling rootstock Prunus cerasifera Ehrh. and the clonal rootstock ‘Docera 6’ (Prunus domestica L. x Prunus cerasifera Ehrh.) to infection with fungal pathogens. Three fungal pathogens Botrytis cinerea (Pers), Penicillium sp (Link) and Monilinia sp. (Aderh and Ruhl.) Honey were used for artificial inoculation. From each scion/rootstock combination, 30 fruits were infected by injecting 25 μl of conidial suspension. From the spread in the experimental orchard pathogens at the most significant frequency were isolated and used. All scion/rootstock combinations had the highest percentage of infected fruits after the inoculation with Monilinia sp. However, the results for the other two pathogens vary – the ‘Topgiant Plus’ cv. is more susceptible to the pathogen Penicillium sp, compared to ‘Jojo’ cv. On the other hand, the fruits of ‘Jojo’ cv. are more susceptible to the pathogen Botrytis cinerea.

Keywords: Docera 6, scion/rootstock combination, Prunus domestica L., Prunus cerasifera Ehrh., Botrytis cinerea (Pers), Penicillium spp. (Link), Monilinia sp.