Morphological characters, inheritance and response to exogenous hormones of a cotton super-dwarf mutant of Gossypium hirsutum

With 2 figures and 4 tables ABSTRACT: A novel super-dwarf mutant, named AS98, was discovered from an interspecific hybrid in 1998. Compared to the normal line LHF10W99, plant height and internode length were significantly shorter in AS98, but it had only slightly (3-5%) fewer internodes. Therefore, the shorter plant height was the result of shorter internodal length. AS98 was crossed with LHF10W99, and the F₁, F₂, BC₁, and BC₂ populations were used for genetic analysis of the dwarf trait. The results showed that the trait was controlled by a single incomplete-dominant gene. Exogenous application of gibberellin acid (GA₃), brassinosteroid and indol acetic acid showed a significant response to GA₃, which could restore plant height in AS98. The results thus provide a basis for utilizing the dwarf trait in breeding and studying the biosynthesis of GA or signal transduction in cotton.