Efficient development of practically usable thermo-photo sensitive genic male sterile lines in wheat through doubled haploid breeding

Background: Two-line hybrid wheat system using thermo-photo sensitive genic male sterility (TPSGMS) is now a dominant and promising approach of wheat heterosis utilization in China. However, during past twenty years only several TPSGMS lines have been capable of practical application in hybrid wheat breeding and production, which reduced the opportunities and efficiency of creating hybrids with strong heterosis. Introducing doubled haploid (DH) breeding could be a helpful strategy to efficiently develop practically usable TPSGMS lines. Results: F 1 s and selected F 2 and F 3 sterile plants from eight crosses made from two commercial TPSGMS lines were used to produce DH lines by using the wheat × maize system. Twenty four elite sterile lines possessing stable sterility, good outcrossing and yield potential, resistance to yellow rust and powdery mildew, and desirable plant height (50-60 cm) were obtained within 4 years through at least one year evaluation. Twenty from twenty four elite lines showed stable sterility in repeated tests of two or three years, will be selected for hybrid breeding. The percentage of elite lines within total tested DH lines produced from filial generations was in the order of F 2 > F 3 > F 1 in this study. Conclusions: Our study shows that DH breeding is more efficient for the selection of traits controlled by recessive gene(s) compared with conventional breeding, especially for the sterility of TPSGMS wheat. Coupling DH techniques with conventional breeding would be an efficient strategy for developing practically usable wheat TPSGMS lines in respect to number and saving time, which is helpful for further improving the efficiency of wheat hybrid breeding. Producing DHs from F 2 generation appeared to be the better choice considering the balance of shortening breeding time and overall breeding efficiency.