Mapping of genes for male-fertility restoration in 'Pampa' CMS winter rye (Secale cereale L.)
- Publication Type
- Journal contribution
- Authors
- Miedaner, T.; Glass, C.; Dreyer, F.; Wilde, P.; Wortmann, H. and Geiger, H.H.
- Year of publication
- 2000
- Published in
- Theor. Appl. Genet.
- Band/Volume
- 101/
- Page (from - to)
- 1226-1233
Hybrid rye breeding and seed production is based on the cytoplasmic male sterility (CMS)-inducing Pampa (P)-Cytoplasm. For restoring male fertility in the hybrids, dominant, nuclear restorer genes are necessary. Effective restorers were recently detected in the German inbred line L18 and in materials originating from the Argentinian rye cultivar Pico Gentario and an Iranian primitive rye accession called IRAN IX. F2 populations were developed for each of these three restorer sources to map the responsible genes by means of RFLP (restriction fragment length polymorphism) markers. Homo- and heterologous DNA probes were used leading to 101 polymorphic marker loci in total. For phenotypic evaluation, 100 to 134 randomly chosen plants from each of the populations were cloned and grown at two or three locations with two plants each. Segregation ratios of pollen fertility in the F2 populations with L18 and IRAN IX were in accordance with a monogenic dominant inheritance. The segregation pattern for Pico Gentario indicated complementary gene action. Major dominant restorer genes were detected on chromosomes 1RS (L18) and 4RL (Pico Gentario, IRAN IX). The gene on 1RS explained 54 % of the phenotypic variation and that on 4 RL 59 % and 68 % in the Pico Gentario and IRAN IX populations, respectively. Additionally, three minor genes from L18 were identified on chromosomes 3RL, 4RL, and 5R. In the Pico Gentario population, a dominant modifier gene contributed by the female parent was found on chromosome 6R that acted epistatic. Map distances between the major restorer loci and at least one flanking marker were small in all three F2 populations (5-6 cM). In Pico Gentario an unfavorable linkage exists between the major restorer gene and a QTL for plant height. Introgression of the major restorer genes detected on chromosomes 1 RS and 4RL should be facilitated by using the closely linked molecular markers.