Development of maize inbred lines with elevated grain methionine concentration from a high methionine population

Methionine is a nutritionally limiting amino acid in poultry diets based on maize (Zea mays L.) grain. Synthetic dietary supplements are available but are costly and not preferred by organic poultry producers. The development of high methionine maize varieties would reduce the need for supplementation. Several approaches have been reported for achieving this goal. Here, we report a novel approach that can produce diverse inbred lines with higher content of methionine than other methods. Inbred lines were developed using doubled haploid technology from a broad-based synthetic population that has undergone mass selection for grain methionine concentration. Out of 18 randomly selected inbred lines, one was significantly higher in methionine concentration than the high methionine check and 11 were not significantly different from it. The inbred lines developed in this way also exhibited useful genetic diversity for several agronomic and kernel quality traits, including flowering date, and orangeness of the kernel. This approach is an excellent complement to other breeding methods for development of varieties for production of poultry feed. Because the approach does not rely on transgenic technology, the resulting lines are suitable for use by organic producers and are well suited to organic production systems.