a self - defoliating cotton plant is provided , as are its progeny , reproductive material , seeds , cuttings , seedlings , protoplasts , leaves , stems , flowers , and cotton . in particular , a cotton plant is provided that comprises a nucleic acid sequence as shown in seq id no : 2 or functional fragments of this nucleic acid . the nucleic acid may be activated by chemical treatment and / or irradiation to effect self - defoliation . self - defoliation advantageously obviates the need to apply defoliants prior to harvesting .