In vivo haploid induction in maize - Performance of new inducers and significance of doubled haploid lines in hybrid breeding.
- Publication Type
- Journal contribution
- Authors
- Röber, F.K., G.A. Gordillo, H.H. Geiger.
- Year of publication
- 2005
- Published in
- Maydica
- Band/Volume
- 50/
- Page (from - to)
- 275-283
In the last three to five years, doubled haploid (DH) lines have increasingly been used in maize (Zea mays L.) research and breeding. This became possible by substantial progress in the in vivo haploid induction technology. Herein, we describe the development and characteristics of a new induction line, RWS, and discuss quantitative genetic and logistic aspects of the use of DH lines in hybrid maize breeding. - Induction line RWS was derived from an F5 plant of a cross between the Russian induction synthetic KEMS and the French induction line WS14. Kernels with a haploid or F1 embryo can be distinguished by means of the expression of the dominant anthocyanin marker gene R1-nj. Misclassification rates based on this marker gene are generally low except for donors carrying anthocyanin inhibitor genes. Reliable estimates of the induction rate were obtained by using tester genotypes with recessive morphological markers. In tests across various induction environments, RWS consistently showed the highest induction rate (8.1% on average) compared to other inducers evaluated herein. - Advantages of using DH lines in hybrid breeding include (1) maximum genetic variance in line per se and testcross trials, (2) high reproducibility of early-selection results, (3) high efficiency in stacking targeted gene arrangements and (4) simplified logistics. High cost-savings are possible due to reduced expenses for the selfing program, handling and shipping of seed batches, and for maintenance breeding. Moreover, outstanding DH lines may be protected and commercialized several seasons earlier than lines developed by inbreeding.