4636

ISU researchers identified a maize chromosomal region and markers associated with the ability of haploid plants to spontaneously double their genome, and thus become DH/inbred lines. Genome doubling without particular treatment, greenhouse cultivation and transplanting can substantially reduce the costs of DH line production. The chromosomal markers combined with the maize of donor lines from the related ISURF 4549 invention can be used to efficiently introgress the trait into maize lines.

To produce commercial hybrid maize one inbred corn line is crossed with a different inbred line. It takes 5-8 generations to develop one inbred line using traditional breeding, while doubled haploid (DH) technology typically produces corn lines in a couple of generations, since the offspring contain only a single genome instead of two. DH has been widely adopted and became the routine process by commercial maize breeders to develop inbred lines. DH commonly involves toxic and costly chemicals (such as colchicine), which are major drawbacks of the current DH approaches.

The related ISURF #4549 invention disclosure identified maize lines with high propensity to haploid genome doubling without the use of chemicals. In this disclosure, our contributors report a chromosomal region and markers associated with the spontaneous haploid doubling effect. This discovery opens the way for rapid introduction of the spontaneous doubling trait into non-doubling germplasm. A candidate gene is being validated.

This technology is related to ISURF 4549: SHGD maize donor line

• Mutation that is easily transferable.

• Avoidance of costly chemical procedures to double haploid genomes.

The genotype allows Agricultural Biotechnology companies to breed (or gene-edit) into their programs that right genetics for high-level SHGD.