Generation and characterization of doubled haploids maize (Zea mays L.) in sub-Saharan Africa

Doubled haploid (DH) inbred lines are an invaluable technology for maize genetics and hybrid breeding. However, in sub-Saharan Africa (SSA), the use of double haploid technology in maize breeding is uncommon, despite its potential to improve the development of new maize varieties. This research, conducted at the Farako-Bâ research station of the Institute of Environment and Agricultural Research (INERA) in Burkina Faso, aimed to evaluate the effects of source germplasm, inducers, and seasons on haploid induction rate (HIR), estimate the misclassification rate of haploid seeds, and determine the chromosome doubling rate. Two haploid inducer lines from CIMMYT were crossed with six open-pollinated varieties (OPVs) and four hybrids from INERA for haploidy induction. Putative haploid seeds were identified using the R1-nj marker. Chromosome doubling of putative haploids was carried out by injecting colchicine solution into the shoot apical meristem. The results revealed significant differences in HIR between OPVs and hybrids and between seasons. The misclassification rate of diploids as haploids for the six OPVs ranged from 12 to 91%, indicating poor expression of the identification marker with some source germplasm. The average chromosome doubling rate was 50%. This study paves the way for the development of DH inbred lines in national maize breeding programs in SSA. Key words: Doubled haploid, in vivo induction, maize, sub-Saharan Africa.