Background and Aims:
Macadamia is endemic to the lowland subtropical rainforest regions of north east NSW and south east Queensland, Australia. The macadamia industry is based on cultivars from two species M. integrifolia and M. tetraphylla. In 2016, a draft genome for Macadamia integrifolia was published. This draft provides access to most macadamia genes but is highly fragmented. In order to anchor chromosomal scale sequence a high density linkage map is required. This project aims to use genome wide single nucleotide polymorphism (SNP) markers to construct a SNP saturated genetic linkage map for M. integrifolia.
Methods:
Mapping populations with over 400 individuals were developed including open pollinated, bi-parental and self pollinated progeny. Total genomic DNA was extracted from individuals in these mapping populations and SNP markers were identified based on a combined process of complexity reduction and next generation sequencing.
Results and conclusions:
Over 3000 SNP markers have been identified and are currently being used to construct maternal, paternal and composite linkage maps. Preliminary results indicate that sufficient data will be generated to construct a high-density composite linkage map. This will improve genome assembly as well as facilitating gene discovery and marker assisted selection in macadamia breeding. The latest results on the development of genetic linkage maps and progress towards anchoring the genome will be presented.
Funding Source:
Horticulture Innovation Australia, Australian Macadamia Society and Southern Cross University.