Bragato Research Institute Advances Sauvignon Blanc Breeding With Cutting-Edge Genetic Tools

The Bragato Research Institute (BRI) in New Zealand is advancing grapevine improvement through its Sauvignon Blanc 2.0 (SB2.0) program, which aims to develop improved clones of the country’s leading wine variety. While the headline goal is to enhance Sauvignon Blanc, the foundational genetics program led by New Zealand Winegrowers (NZW) has already delivered significant assets for the wine industry. These include new disease and virus testing capabilities, scalable screening tools, modern genetic fingerprinting methods, robust data systems, and stronger partnerships both locally and internationally.

Dr. Darrell Lizamore, SB2.0 Programme Manager, highlights the progress made at BRI’s new breeding vineyard, where the vine population is expected to reach 10,000 this season. This vineyard serves as a visible sign of advancement in developing and selecting new clones. However, much of the work happens behind the scenes, where modern resources have been established to accelerate vine production and screening while reducing risk and cost.

Building an effective team was one of the early challenges for SB2.0. The program required a mix of scientists, industry experts, technical advisors, investor representatives, and communications specialists. Despite limited resources compared to other breeding programs, BRI formed a team with expertise in genetics, plant physiology, bioinformatics, molecular biology, and viticulture. Partnerships with local and international experts have helped align research innovation with industry needs.

Accurate measurement is crucial in plant breeding to identify outstanding individuals among large populations. Over the past year, SB2.0 invested in optimizing trait measurement methods central to the program. This included new equipment, training, and data systems that improve reliability and efficiency in selection processes. These resources are now available for broader industry use to address future challenges such as climate adaptation and input reduction.

Molecular diagnostics have been implemented to confirm the absence of phylloxera in the breeding vineyard using PCR and amplicon sequencing from soil samples. In-house protocols for leafroll virus detection allow year-round testing of bud sports identified by growers. The Vure platform enables growers to report unusual vines during routine vineyard work.

In 2023, BRI completed a reference genome for Sauvignon Blanc, providing a baseline for identifying genetic changes among clones. The team has since characterized differences among commercial clones and about 100 new clones produced by SB2.0. This work allows for easy identification of clones through DNA testing and a better understanding of how genetic changes affect traits. The genome assembly pipeline has also been used for other varieties such as Chenin Blanc, Chardonnay, Pinot Noir, and rootstocks.

To streamline genetic testing, BRI developed new DNA extraction and sequencing methods that reduce costs per vine and detect a wider range of genetic differences. Bioinformatics pipelines reliably identify clonal variation and map molecular switches controlling trait expression. Data is managed in a digital database with barcode integration and QR-code identifiers, running on national high-performance computing infrastructure.

The institute has modernized its national vine collection database using these tools and is studying how terroir and environmental stress affect grapevine traits. Powdery mildew screening has become more scalable through standardized inoculum production and automated detached-leaf assays using the Blackbird imaging platform developed by USDA/Cornell. Artificial intelligence distinguishes mildew from leaf hairs in large image datasets within hours.

This technology supports fungicide resistance testing and rapid diagnostics for local powdery mildew isolates. For drought resilience studies, BRI ran glasshouse trials with 80 vines to find scalable indicators of water-use efficiency. Collaboration with Bordeaux Sciences Agro introduced rapid measurement tools for photosynthesis and transpiration. Frost tolerance screening combines lab experiments with field exposure using robotic imaging approaches guided by Markus Keller at Washington State University.

After four years of sterile plantlet production, BRI can now move new clones from lab to nursery to vineyard with over 97% survival rates. Special management programs accelerate vine growth so screening can begin sooner. Experiments in Marlborough are testing propagation strategies such as top-grafting buds onto established vines to speed up commercial trials.

New Zealand’s government recently proposed legislation updating gene technology definitions. BRI’s science team has contributed technical expertise to support education on gene technologies and market access considerations within the wine industry. The team has tested non-transgenic editing steps that could validate breeding strategies early on.

Internationally, SB2.0 has attracted collaboration opportunities with grape breeders in Europe and North America through visits to institutions like UC Davis, Cornell University, USDA, E.&J. Gallo Winery, Geisenheim University (Germany), ICVV (Spain), and hosting breeders from Switzerland and the United States.

Locally, the platform connects grantor companies, grower communities, and industry committees with science through workshops and meetings that foster two-way learning about breeding priorities.

The next phase of SB2.0 will focus on selecting traits that make Sauvignon Blanc more resilient to mildew, drought, and frost by running objective screening workflows linked to genetics before moving promising material into pre-commercial trials. Tools developed by SB2.0 are already supporting projects such as fungicide resistance surveys, RNA-based treatments for leafroll virus, diversity studies on Pinot Noir clones, and breeding disease-tolerant varieties with the Bioeconomy Sciences Institute.

The program not only aims to develop improved Sauvignon Blanc clones but also strengthens New Zealand’s capacity for ongoing grapevine improvement as climate conditions change and disease pressures evolve through innovation and collaboration across the wine sector.