Sub-grant for DH Maize: A Double Haploid Facility for Strengthening Maize Breeding Programs in Africa (the "Grant")

The goal of this project is to develop an alternative method for chromosome duplication of in vivo maternal haploids with a success rate similar to or better than the conventional colchicine treatment but avoiding its disadvantages.

Production of doubled haploid (DH) lines by in vivo haploid induction in maize (Zea mays L.) has revolutionized hybrid breeding in this crop during the past decade. It is easy and simple to apply in any breeding program without the need for expensive wet labs. However, in vivo production of doubled haploid (DH) lines in maize routinely involves artificial chromosome doubling by colchicine treatment of seedlings. Because colchicine is a hazardous chemical, replacing it by less toxic alternatives would be highly desirable.

Significant progress has been made, in that a treatment based on herbicides, which have a much lower toxicity than colchicine, has been developed with a chromosome doubling rate near that of colchicine (Melchinger and Molenaar et al., 2016). Research is underway on further improvements of such less-toxic alternatives to colchicine to make rapid development of inbred lines safer and less costly.

Literature

Melchinger, A.E., W.S. Molenaar, V. Mirdita, and W. Schipprack. 2016. Colchicine alternatives for chromosome doubling in maize haploids for doubled- haploid production. Crop Sci. 56:559-569.