The present invention provides a novel, high-effect plant growth regulator in a crop culture such as a banana culture.The plant growth regulator for cultivating plants is characterized by comprising a heterocycle compound represented by the following general formula (I) as an active component:(in the formula, A represents a nitrogen atom or C-hal (wherein hal represents a halogen atom) B represents a nitrogen atom R1 represents a halogen atom, a C1-C6 alkyl group or a C3-C6 cycloalkyl group and R2 represents a hydroxyl group, a C1-C6 alkoxy group, a benzyloxy group, a benzyloxy group having at least one or more, same or different substituents selected from a halogen atom, a cyano group, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group or a C1-C6 haloalkoxy group on the ring, a phenylamino group, or a phenylamino group having at least one or more, same or different substituents selected from a halogen atom, a cyano group, a C1-C6 alkyl group, a C1-C6 haloalkyl group, a C1-C6 alkoxy group ora C1-C6 haloalkoxy group on the ring).本發明提供一種在香蕉栽培等作物栽培中新穎且效果高之植物成長調節劑。一種栽培植物用之植物成長調節劑,其特徵為包含做為有效成份之式(I)所示之雜環化合物,(式中,A為氮原子或C-hal(式中,hal為鹵原子);B為氮原子;R1為鹵原子,C1-C6烷基或C3-C6環烷基;R2為羥基,C1-C6烷氧基,苄氧基,於環上具有1個以上選自鹵原子、氰基、C1-C6烷基、C1-C6鹵烷基、C1-C6烷氧基或C1-C6鹵烷氧基之相同或不同取代基之苄氧基,苯胺基,或於環上具有1個以上選自鹵原子、氰基、C1-C6烷基、C1-C6鹵烷基、C1-C6烷氧基或C1-C6鹵烷氧基之相同或不同取代基之苯胺基)。
