Toward a Cost-Effective Fingerprinting Methodology to Distinguish Maize Open-Pollinated Varieties

In Africa, many smallholder farmers grow open-pollinated maize (Zea mays L.) varieties (OPVs), which allow seed recycling and outyield traditional unimproved landraces. Seeds of productive OPVs are provided to farmers, often by nongovernmental organizations (NGOs) that help farmers access improved seeds, particularly following disasters in which original seed is lost. However, NGOs often rely on local seed suppliers to provide seed, and in some years the seeds provided to the farmers are suspected not to be of the promised variety. Here we present methodology to prove within a high level of confidence if two samples of seeds are the same genetic population or not, despite the difficulties involved in fingerprinting heterologous populations. In addition to heterogeneity within populations, difficulties can include sampling errors, differences in the fields or years in which the seeds were multiplied, and seed mixing. Despite these confounding sources of variation, we show the possibility to conclusively differentiate each of the populations used in this work. This methodology will allow breeders, seed companies, government agencies, and NGOs to ensure the purity and identity of high-yielding, locally adapted OPVs reach farmers so they can generate the highest yields possible in their fields.