Molecular marker-assisted selection of the ae alleles in maize.

The ae (amylose extender) recessive mutant alleles in maize are an important genetic resource for the development of high-amylose cultivars. On the basis of ae allele sequences (from the National Center for Biotechnology Information), the ae mutant alleles were cloned from high-amylose maize and the allelic Ae gene from common maize luyuan92 inbred lines. Five pairs of primers were designed to screen for a molecular marker of ae alleles, yielding a dominant molecular marker, ae474. We used 53 types of high-amylose maize and common maize inbred lines and their hybrid and backcross offspring for verification and analysis. The ae dominant molecular marker was effective in selecting for the ae alleles and for biological materials with a high-amylose genotype. Presence and absence of the marker in the offspring conformed to the expected Mendelian ratios. Using this marker, we were able to detect the ae alleles in a backcross and its second generation more efficiently (53.3 and 73.3%, respectively) than was possible without marker selection. These data indicate that the marker can be used as a tool to improve selection efficiency and accelerate the cultivation of new varieties of high-amylose maize.