PROBLEM TO BE SOLVED: To provide a novel plant growth regulator.SOLUTION: A plant growth regulator contains a compound represented by formula [I] or a salt thereof as an active ingredient.SELECTED DRAWING: None【課題】新規な植物生長調節剤を提供すること。【解決手段】式〔I〕で示される化合物又はその塩を有効成分として含有する植物生長調節剤。【選択図】なし