Inheritance and fine mapping of fertility restoration for cytoplasmic male sterility in Gossypium hirsutum L.

Abstract.

Genetics of CMS fertility restoration was presented through the analysis of classic genetics and molecular markers. Based on F₂ segregation of the crosses between CMS and the restoring lines, the testcrosses and F₁ × F₁ populations, together with RAPD and SSR mapping, one dominant gene was identified to control the CMS fertility restoration in cotton. The strategy of genotype representation analysis (GRA) was put forward to screen the markers linked with the Rf ₁ locus. Using 1,025 random decamer primers and 282 pairs of SSR primers, two RAPD and three SSR markers were identified to be closely linked to the Rf ₁ gene. Among the five markers, three were co-dominantly inherited. Additionally, based on the analysis of monosomic and telesomic lines with one SSR maker, the Rf ₁ locus could be located on the long arm of chromosome 4. The molecular markers available here are helpful in the development of the elite restoring lines in cotton by marker-assisted selection.