4549

ISU researchers have bred donor maize lines with increased propensity to  spontaneously double their haploid genomes, and thus become doubled haploid (DH)/inbred lines. This finding open a path to reduce the costs associated with DH maize production. The donor lines of this invention and associated DNA markers of ISURF invention disclosure 4636 are jointly available for licensing.

 

Doubled haploid (DH) technology has been widely adopted by commercial maize breeders. Haploid genome doubling is one of the most critical steps during development of DH lines. Artificial genome doubling, which commonly involves toxic and costly chemicals, is a major challenge in DH process. An alternative would be to have haploids that become fertile without particular treatment, i.e. by spontaneous haploid genome doubling (SHGD). The challenge is to find or develop lines that have a very high propensity for SHGD.

ISU researchers screened a very large number of maize lines looking for high SHGD lines. They identified genotypes with high SHGD ability, where DH lines can be derived at equal or higher rates using the SHGD genetic mechanism compared to artificial treatment. By crossing different lines with SHGD, they were able to derive novel DH lines, where derived haploid plants are close to 100% fertile and able to set seed without artificial treatment. This simplifies the handling of haploids dramatically, as haploid seed can be sown directly, rather than first cultivated in the greenhouse, then treated and transplanted with vegetable planters (or manually). 

Donor lines and SHGD associated markers are available for licensing.

This technology is related to ISURF 4636: Gene controlling spontaneous haploid genome doubling in maize

• Potential to improve the efficiency and costs of producing inbred maize in relation to current methods.

• It would remove greenhouse costs, transplanting, labor of treating haploids.

• It would eliminate the need of using a hazardous doubling agent such as colchicine.

The genotype would allow Agricultural Biotechnology companies to breed into their programs the right genetics for high-level SHGD.