Amplification products in four cotton species using subgenome-specific qPCR primer pairs. First line includes amplified results from A-genome specific primers; second line includes amplified results from D-genome specific primers. "M" represents marker, "A" represents G. herbaceum var. africanum, "D" represents G. raimondii, "T" represents G. hirsutum acc. TM-1, "H" represents G. barbadense cv. Hai7124. Numbers represent the sizes of the makers (bp).