Zyprian, E. M. | Search bioRxiv

bioRxiv2022

Phased grapevine genome sequence assembly of an Rpv12 carrier for exploration of Rpv12 associated positional and functional Plasmopara viticola resistance genes

The downy mildew disease caused by the oomycete Plasmopara viticola is a serious threat for grapevine and can cause enormous yield losses in viticulture. The quantitative trait locus Rpv12, mediating resistance against P. viticola, was originally found in Asian Vitis amurensis. This locus and its genes were analyzed here in detail. A haplotype-separated genome sequence of the diploid Rpv12-carrier Gf.99-03 was created and annotated. The defense response against P. viticola was investigated in an infection time-course RNA-Seq experiment, revealing approximately 600 up-regulated Vitis genes during host-pathogen interaction. The Rpv12 regions of the resistance conferring and the sensitivity encoding Gf.99-03 haplotypes were structurally and functionally compared to each other. Two different clusters of resistance-related genes were identified within the Rpv12 locus. One cluster carries a set of four differentially expressed genes with three ACCELERATED CELL DEATH 6-like genes. The other cluster carries a set of six resistance gene analogues related to qualitative pathogen resistance. The Rpv12 locus and its candidate genes for P. viticola resistance provide a precious genetic resource for P. viticola resistance breeding. Newly developed co-segregating simple sequence repeat markers in close proximity to the R-genes enable its improved applicability in marker-assisted grapevine breeding.

plant biology↗

bioRxiv2020

Same same but different: Cluster architecture variation in five 'Pinot Noir' selection lines correlates with differential expression of three transcription factors and further growth related genes

Grapevine (Vitis vinifera L.) is an economically important crop that needs to comply with high quality standards for fruit, juice and wine production. Intense plant protection is required to avoid losses caused by fungal infections. Grapevine cultivars with loose cluster architecture enable to reduce protective chemical treatments due to their enhanced resilience against fungal infections such as Botrytis cinerea induced grey mold. A recent study identified transcription factor gene VvGRF4 as determinant of inflorescence structure in exemplary samples of loose and compact quasi-isogenic Pinot Noir clones. Here, we extended the analysis to 12 differently clustered Pinot Noir clones originating from five different clonal selection programs. Differential gene expression of these clones was studied in three different locations over three seasons in demonstrative vineyards. Two phenotypically contrasting clones were grown at all three locations and served for standardization of downstream analyses. Differential gene expression data were correlated to the phenotypic variation of cluster architecture sub-traits. A consistent differential gene expression of VvGRF4 in relation to loose clusters was verified over the different environments and in the extended set of Pinot Noir clones. In addition, 14 more genes with consistent expression differences between loosely and compactly clustered clones independent from season and location were identified. These genes show annotations related to cellular growth, cell wall extension, cell division and auxin metabolism. They include two more transcription factor genes.

plant biology↗