A Phocus on Phenotyping: Opportunities and Challenges in Local and Centralized Trait Evaluation from the VitisGen Experience

The integration of relevant genetic resources, robust phenotypes, and cutting-edge genotypic data is a challenge that individual scientists rarely overcome successfully. In the USDA-NIFA VitisGen project ( www.vitisgen.org ) for grapevine cultivar improvement, our research team has pursued a shared strategy 1) to maintain breeding germplasm locally, 2) to collect and analyze high-resolution genotypic data centrally, and 3) to collect and analyze phenotypic data both locally and in phenotyping centers specializing in fruit chemistry, low temperature response, and powdery mildew resistance. In the process of genotyping 28,000 individuals and collecting millions of phenotypic data points, challenges and unexpected opportunities arose from our approach. Here, we will ‘Phocus’ on Phenotyping, sharing our experiences and highlighting what seems to be working and not working in both local and central trait evaluation, based primarily on genetic analysis. These stories and results may facilitate both cultivar improvement and strategies for genetic analysis of traits.