4099

Iowa State University researchers have developed a new haploid inducer for specialty maize that can overcome dent sterility used in popcorn and organic breeding programs, as well as two selectable marker – R1-nj and Pl1 – for haploid selection.

Lines will be available in the Fall of 2015

Inbred corn lines have two identical copies of their genome, and are valuable breeding resources since offspring are identical to their parent. Since offspring of hybrids are genetically segregating, hybrid seed needs to be generated from genetically stable, parental inbred lines. Development of traditional corn inbred lines starts from heterozygous plants and requires continued self-pollination, which takes five to eight generations before an inbred line is pure enough to be combined with another inbred line to create a hybrid. Doubled haploid (DH) technology can be used to produce pure, inbred corn lines in just two generations, since the initial “haploid” offspring contain only a single genome instead of two, which is then doubled in this DH procedure.  So-called inducer lines are used as pollinators in the DH approach. 

The DH technology  has found broad acceptance in corn breeding. Specialty breeders such as popcorn and sweet corn breeders and organic growers use the dent sterility trait to prevent undesired field corn from pollinating their lines. The specialty inducer developed can be used for all donor materials, and especially in popcorn and organic breeding programs that use dent sterility (Ga1), to prevent uncontrolled pollinations with genetically modified field corn.
The inducer has two selectable markers for haploid identification: the kernel color marker R1-nj that allows haploid selection in the seed, and the root color marker Pl1 that allows haploid selection after germination in young seedlings. Inducer lines are adapted to the Midwest growing season and have comparable induction rates to previously released inducer lines.

This technology is related to ISURF #4065: Midwest Adapted Haploid Inducer for Maize and ISURF 5202: C1-I haploid inducer

• Simple dual seed color and root color selection increases the number of true positives.

• Haploid inducing rates comparable to European inducers but better suited to Midwest corn growing season

• Able to overcome dent sterility (Ga1)

Plant Breeding

Tangible Property