Haploid production in durum wheat by the interaction of Aegilops kotschyi cytoplasm and 1BL/1RS chromosomal interchange.

The present study describes the development of an alloplasmic haploid-inducer in durum wheat cv 'Cando'. This cultivar possesses the homozygous wheat-rye translocation 1BL/1RS from the 6x-wheat cv 'Veery'. The nucleus of 4x-'Cando-Veery 1BL/1RS' was introduced into Aegilops kotschyi cytoplasm by initially using (kotschyi)-Salmon as the maternal parent. In the cross of this alloplasmic durum line with 'Cando-Veery 1BL/1RS', which was used as the recurrent pollen parent, haploids (n=14) were produced. The frequency of haploids increased from 5.7% in the F1 generation to 14% in the BC1 generation. The presence of rye chromosome arm 1RS and the concomitant loss of 1BS in '(kotschyi)-Cando-Veery 1BL/1RS' are necessary for haploid induction. Proposals are made which may enable the use of haploids produced by nucleo-cytoplasmic interactions in future wheat breeding programs.