Breeding of Candidate Lines for Male Sterility-Maintainer by Anther Culture for Hybrid Wheat Production Using an S^v Type Cytoplasm and a 1BL-1RS Chromosome

Abstract

We previously proposed a new breeding scheme to develop hybrid wheat utilizing male sterility induced by the interaction between the S^vtype cytoplasm of Ae. kotschyi and the IBL-1RS chromosome (Toriyama et al. 1991, 1993). In our proposed scheme male sterility-maintainer lines can be produced by two ways, i. e. the backcrossing method (Nonaka et al. 1993) and anther culture. This article reports the results of anther culture. Donor for the 1BL-1RS chromosome, namely, the strain 911-B-8-10 (abbreviation, st. 911) was crossed to 13 Japanese wheat cultivars. The anther culture was conducted using the F₁ and B₁F₁ plants. Frequency of embryo formation in the Fls was higher than that in the parental Japanese cultivars. The frequency observed in the B₁F₁s was lower than that in the F₁s. High frequencies of embryo formation in st. 911 and the Fls were attributable in part to the 1BL-1RS chromosome. Since the leaf rust resistance gene Lr 26 was located on the 1RS chromosome arm, regenerated haploid seedlings were artificially inoculated by leaf rust (race 21B) to select resistant ones. Doubled haploids with resistance were crossed with (S^v)-Chinese Spring having the IB chromosome and with (S^v)-Salmon having the 1BL-1RS chromosome. The F₁s of the former cross showed high selfed fertility, while the Fls of the latter showed complete male sterility. This means that resistant doubled haploids obtained by anther culture can be used as a maintainer for developing male-sterile line.