Rootstocks are an important component of viticulture, with choices often based on experience and current vineyard conditions. The ever-changing climate and water availability requires a future-proof plan to ensure sustainable winegrowing in New Zealand.
BRI has recently invested in setting up a rootstock trial block in Marlborough, with the aim of identifying rootstocks with improved performance under water deficit. This consists of Sauvignon Blanc (SB) vines grafted onto 15 rootstocks, planted in a block design with three different irrigation levels. This new project leverages this powerful resource together with BRI’s established capability in SB genomics and epigenomics. It aims to build knowledge on rootstock-scion molecular communication in grafted SB vines, focusing on small RNA molecules. Small non-coding RNAs play important roles in plant gene regulation and have been reported to move bilaterally across graft junctions, and potentially act as signal molecules contributing to traits of the scions of grafted plants.
This project aims to identify and functionally characterise these mobile genetic elements, that contribute to the phenotypic traits of two rootstocks with contrasting drought tolerance properties under water deficit conditions. These can serve as genetic markers for grapevine scion and rootstock breeding or as targets for grapevine improvement through genetic or non-genetic modification approaches.