Maximising the rate of parental improvement in the Australian Sugarcane Breeding Program : final report 2008/319

Abstract

Parental improvement is an integral and key component in commercial genetic improvement programs. Its importance has not been fully realised, and even ignored in SRA Sugarcane Breeding Programs around the world, partly due to the fact that a sugarcane variety is clonally deployed in commercial production rather than distributed as seed from parental lines. At the beginning of this project, a survey of four sugarcane breeders in the SRA Sugarcane Breeding Program indicated subjective methods were used to select parents and for determining crossing combinations. A parental clone may be assigned a predicted breeding value (PBV) based on (i) performance of its progeny in progeny assessment trials or (ii) predicted genetic value (PGV) on its own phenotype in clonal assessment trials (PGV-CAT) or final assessment trials (PGV-FAT). Given these mixed sources of information, it was not clear how to weigh these sources objectively. Despite the potential benefits from the rapid development of technology in molecular markers, the effectiveness for sugarcane parental improvement was untested. This project was designed to address these issues with the aim of maximising the rate of genetic gains.