Improving the selection efficiency in potato breeding

Abstract

Current Australian potato cultivars suffer from a number of production and quality issues. Commercial cultivar development within Australia used a conventional potato breeding strategy, with outcrossing, and then screening of derived lines to identify improved cultivars, although we have been investigating methods to make the program more efficient. Implementation of marker-assisted selection (MAS) is highly desirable to increase efficiency, and our initial targets for MAS have been qualitative disease resistances. Two diseases of concern within the Australian potato industry are potato cyst nematode (PCN) (Globodera rostochiensis Ro1) and Potato virus Y (PVY), so we investigated markers for these diseases, including a potentially diagnostic marker, 57R, for PCN Ro1. As the majority of the target traits for the breeding program are quantitative and controlled by multiple to many genes, we have also investigated a quantitative genetic analysis technique used in livestock breeding for these complex traits to develop estimated breeding values (EBVs) for them. The breeding program has now developed a breeding scheme using a combination of MAS, EBVs and conventional screening methods for early-generation selection of cultivars with multiple desirable traits. The application of these new techniques, alongside conventional screening, will see a reduction in the breeding cycle and the cost of breeding, as well as improving genetic gain in a range of traits.