A complete set of monosomic alien addition lines developed from Gossypium anomalum in a Gossypium hirsutum background: genotypic and phenotypic characterization.

Gossypium anomalum (B1B1) is a valuable wild resource for the genetic improvement of G. hirsutum (A(1)A(1)D(1)D(1)) in terms of fiber quality and disease and pest resistance, but the inherent difficulties in distant hybridization hinder its utilization in breeding programs. Monosomic alien addition lines (MAALs) are powerful tools for interspecific gene transfer. First, to access useful genes from G. anomalum, a fertile hexaploid from G. hirsutum x G. anomalum was obtained and then additional chromosomes were selected using SSR markers in successive backcrosses and self-crossing from BC2F1 to BC4F4. Finally, a complete set of 13 MAALs were developed. All the MAALs were confirmed by chromosome-specific anchored SSRs and genome-wide resequencing. The MAALs demonstrated abundant variation in morphological, agronomic, yield-related, and fiber quality traits. MAAL_3B had excellent fiber strength and fineness, indicating that the transmitted chromosome may carry desirable genes for the observed phenotypes. This complete set of MAALs will provide important genetic bridge material for the identification and introgression of favorable genes from G. anomalum and lay an important foundation for the genetic improvement of cotton.