Growth and gibberellin relations of the extreme dwarf dx tomato mutant

The extreme dwarf d ^x tomato ( Lycopersicon esculentum Mill.) mutant has very short internodes which were found to contain shorter and fewer epidermal cells. The leaves are highly abnormal. The mutant showed a substantial stem growth response to GA₃, without approaching normal stature or morphology. The active gibberellin GA₁ and its precursors GA₁₉ and GA₂₀ were identified by coupled gas chromatography-mass spectrometry (GC/MS) in d ^x shoots. Quantitative GC/MS revealed that GA₂₀ accumulated to far higher levels than normal in stems and leaves of the mutant.