australe monosomic alien chromosome addition lines (MAAL) using a combination of morphological survey, microsatellite marker-assisted selection, and molecular cytogenetic analysis. The amphidiploid (2n?=?78, AADDGG) of G. australe and G. hirsutum was consecutively backcrossed with upland cotton to develop alien addition lines of individual G. australe chromosomes in G. hirsutum. From these backcross progeny, we generated the first complete set of chromosome addition lines in cotton; 11 of 13 lines are monosomic additions, and chromosomes 7Ga and 13Ga are multiple additions. MAALs of 1Ga and 11Ga were the first to be isolated. The chromosome addition lines can be employed as bridges for the transfer of desired genes from G. australe into G. hirsutum, as well as for gene assignment, isolation of chromosome-specific probes, flow sorting and microdissection of chromosome, development of chromosome-specific ‘‘paints’-for fluorochrome-labeled DNA fragments, physical mapping, and selective isolation and mapping of cDNAs for a particular G. australe chromosome." />