Can fungal volatile organic compounds (FVOCs) provide control of Sclerotinia sclerotiorum in potato?

Abstract

Sclerotinia sclerotiorum is one of the most devastating soil-borne pathogens of potato in the world, causing white mould disease. In vitro experiments suggest that two fungal organic compounds (FVOCs) from Trichoderma atroviride “type B” have an antagonistic effect on S. sclerotiorum. The main objective of this study is to evaluate these two FVOCs for bio-control of this pathogen in three environmental conditions: in a glasshouse, a controlled environment and in the field. S. sclerotiorum inoculum will be grown in wheat bran and mixed into the growing medium before the potato tubers are planted. The FVOCs will be infused into an alginate: silicate system as beads then applied adjacent to the tubers. Disease progression in the ‘pathogen only’ control and for the two FVOC treatments will be recorded throughout the growing season. At harvest, yield will be determined and both leaf and tuber samples taken for analysis: chitinase, B-1,3 glucanase, protease inhibitors, phenolic compounds, peroxidase and catalase activity will be recorded, and a transcriptome analysis will be conducted to determine any up/down regulation of genes related to plant defence systems. Our hypothesis is that one or both FVOCs will, via chemical signalling, allow the potato plant to upregulate its defence pathways, and thus better withstand the pathogen attack.