Bulked Genetic Characterization of Ghanaian Maize Landraces.

Abstract

Maize (Zea mays) was first introduced into Ghana over 5 centuries ago and remains the most important cereal staple grown in all agro-ecologies across the country. Yield from farmers' fields are low, which is attributed in part to farmer's preferences and/or reliance on local landraces for cultivation. Research efforts are underway to improve some of these landraces for improved productivity by local farmers. Seeds of maize landraces cultivated in all agro-ecologies were collected for genetic characterization using a bulk fingerprinting technique. In all, 20 populations from Ghana and 4 control populations from Latin America were characterized. Bulked DNA from 15 plants per population was extracted and amplified via PCR with 20 SSR markers spanning the maize genome. The dendrogram obtained from analyses of the marker data grouped the landraces into two broad groups corresponding to the north and south of the country. The control genotypes were outliers, different from the Ghanaian landraces as expected. Genotypes from Ashanti, which is centrally located, fell into both major clusters. A Structure analyses grouped the genotypes into 5 clusters which were not fully distinct according to F statistics. The results suggest that breeding efforts should target agro-ecologies and farmers should have access to performance data on each cultivar developed for their growing conditions so that they may choose the most productive, rather than the current practice whereby farmers plant whatever comes their way.