Rootstocks are the link between the soil and scion in grapevines, can provide tolerance to abiotic and biotic stresses, and regulate yield and grape quality. The vascular system of grapevine rootstocks in nurseries is still an underexplored niche for research, despite its potential for hosting beneficial and pathogenic microorganisms.
The purpose of this study was to investigate the changes in the composition of fungal communities in 110 Richter and 41 Berlandieri rootstocks at four stages of the grapevine propagation process. Taxonomic analysis revealed that the fungal community predominantly consisted of phylum Ascomycota in all stages of the propagation process. The alpha diversity of fungal communities differed among sampling times for both rootstocks, with richness and fungal diversity in the vascular system decreasing through the propagation process. The core microbiome was composed of the genera Cadophora, Cladosporium, Penicillium and Alternaria in both rootstocks, while the pathogenic genus Neofusicoccum was identified as a persistent taxon throughout the propagation process. FUNguild analysis showed that the relative abundance of plant pathogens associated with trunk diseases increased towards the last stage in nurseries. Fungal communities in the vascular system of grapevine rootstocks differed between the different stages of the propagation process in nurseries. Numerous genera associated with potential biocontrol activity and grapevine trunk diseases were identified. Understanding the large diversity of fungi in the rootstock vascular tissue and the interactions between fungal microbiota and grapevine will help to develop sustainable strategies for grapevine protection.
This study has been performed by the BIOVITIS research group of the ‘Instituto de Ciencias de la Vid y del Vino (ICVV)’ in collaboration with INRAE in Bordeaux, Universidad de la República (Uruguay) and Mendel University (Czech Republic). This work has been supported by the José Castillejo program (CAS 18/00065). Results of this study has been published in Journal of Fungi:
D. Gramaje, A. Eichmeier, M. Spetik, M.J. Carbone, R. Bujanda, J. Vallance, P. Rey. 2022. Exploring the temporal dynamics of the fungal microbiome in rootstocks, the lesser-known half of the grapevine crop. Journal of Fungi 8:421.