Grapevine responses to Botrytis cinerea infection: noble rot versus grey rot

Abstract

The intricate relationship between the necrotrophic pathogen Botrytis cinerea and grape berries (Vitis vinifera spp.) can lead to the development of either the desirable noble rot (NR) or the unfavourable grey rot (GR), depending on the prevailing weather conditions. In this research, the focus is on the functional gene set of V. vinifera by conducting multidimensional scaling, which is then followed by differential expression and enrichment analyses. The aim of this study is to identify the variations in gene expression among grape berries during the phases of grey rot, noble rot, and developing rot (DR, in its initial stages). The grapevine transcriptome during the NR phase showed notable differences compared to that at the DR and GR stages, which revealed strong similarities. Likewise, various pathways associated with plant defence, such as hypersensitive responses to plant-pathogen interactions, were discovered to be enriched. The analysis results revealed a possible plant stress response pathway (SGT1 activated hypersensitive response) that was overexpressed in the GR berry while being downregulated in the NR berry. The research indicated a reduction in defence-related V. vinifera genes during the NR phases, exhibiting significant variability in functions, especially in enriched pathways. This suggests that the plant is not actively protecting itself against Botrytis cinerea, which is otherwise found on its surface with significant biomass. This finding underscores the hypothesis that during the NR phase, the grapevine and the pathogenic fungi engage in a balanced interaction, in contrast to the early phases of botrytis infection, which appear to be an aggressive interaction between fungus and plant, irrespective of whether the result is grey or noble rot.