Genetic gain in maize breeding in Eastern and Southern Africa
Genetic gain evaluation enables plant breeding organization to measure and adjust breeding programs on the basis of their performance. Establishing a baseline of genetic gain also allows the value of incorporating new tools, such as molecular markers and high-throughput phenotyping tools, into breeding programs to be quantified in terms of genetic improvement.
New articles in Crop Science report on the first studies to establish genetic gain within the International Maize and Wheat Improvement Center’s (CIMMYT) hybrid maize and open-pollinated varieties (OPV) breeding programs.
Significant genetic gain in grain yield was found under optimal conditions and abiotic and biotic stress environments in both the hybrid and OPV breeding programs. These results confirm the value of investing in breeding to deliver farmers improved varieties with increased yield stability in low-input and rainfed environments. Rates of gain in maize yields in both programs were found to be comparable to other regions of the world.
However, greater gains are needed to ensure smallholder farmers in eastern and southern Africa are able to offset potential losses in maize yields under climate change. Yields in both the hybrid and OPV pipelines showed no indication of reaching plateaus, confirming further gains can be made. These studies review how CIMMYT aims to further increase genetic gains by incorporating new phenotyping tools, trait-linked markers for key diseases, doubled haploid technology, and improved decision support tools into the maize breeding pipeline.