Method for identifying whole-set chromosomes of cotton A genome and A sub-genome

The invention belongs to the field of molecular cytogenetics, and particularly relates to a method for identifying a cotton A genome or A sub-genome chromosome. 299N22 is cloned by BAC from a sea island cotton pima-90 BAC library, and BAC-FISH is carried out in different cotton seeds. Thus, the cotton A genome or A sub-genome chromosome can be obviously recognized; obvious signals are displayed on the A sub-genome chromosomes of five tetraploid cotton seeds and A genome chromosomes of two diploid cotton seeds by taking the BAC cloning as a probe; and the signals are distributed on all chromosomes while no signal is formed on D genome and D sub-genome chromosomes. The BAC-FISH method is adopted by using BAC cloning disclosed by the invention, and the whole-set chromosome of the A genome or the A sub-genome can be rapidly identified.