Submitted to: Corn International Conference Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 6, 1995
Publication Date: N/A
Interpretive Summary: A major goal of some of the recent experiments in corn is to use genetic tags (markers) to increase the efficiency of plant breeders by reducing the length of time for developing new hybrids, and at the same time, increase breeding precision. These genetic markers facilitate the transfer of genetic factors between corn lines or strains. Using this technology, two "enhanced" strains (inbreds lines) of corn were produced. When these "enhanced" lines were crossed to produced a new hybrid, this "enhanced" hybrid produced about 10% more grain (15 to 19 bushels per acre) than the hybrid from the original lines. These results demonstrated that marker- facilitated breeding techniques can be successfully used to manipulate complexly inherited traits such as grain yield.
Technical Abstract: Six chromosomal segments were identified in corn inbred line Tx303 that (if transferred into inbred line B73) would be expected to enhance the B73 X Mo17 hybrid response for grain yield. Likewise, another six segments were identified in Oh43 for transfer into Mo17 to enhance this hybrid. Marker-facilitated backcrossing was used for transferring one to four of the desired segments into the target lines, B73 and Mo17. Following two cycles of testing of the "enhanced" B73 and "enhanced" Mo17 lines in appropriate hybrid combinations, results from replicated field evaluations grown in two years showed that the grain yield of the better "enhanced" hybrids exceeded the unimproved B73 X Mo17 hybrid and a high yielding commercial check by at least 10% (15 to 19 bushels per acre). These studies demonstrated that marker-facilitated techniques can be successfully employed for introgression of desired alleles at multiple loci for manipulation of complexly inherited traits in maize such as grain yield.