Plant growth inhibiting agent, and plant growth inhibiting method using same

A plant growth inhibiting agent comprising, as an active ingredient, at least one compound selected from the group consisting of a compound represented by the following formula (I′) and a salt thereof:

• wherein
• R1a represents a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C6 to C14 aryl group, a substituted or unsubstituted C3 to C13 heteroaryl group, a substituted or unsubstituted C7 to C30 arylalkyl group, or a substituted or unsubstituted C4 to C30 heteroarylalkyl group;
• R2 represents a substituted or unsubstituted C1 to C20 alkylene group, a substituted or unsubstituted C6 to C14 arylene group, a substituted or unsubstituted C3 to C13 heteroarylene group, or a divalent linking group consisting of a combination thereof,
• R3a represents OH, a substituted or unsubstituted C1 to C6 alkoxy group, or a group represented by a formula:
• N(R4)2 wherein R4 represents a hydrogen atom or a substituted or unsubstituted C1 to C6 alkyl group, and two R4 together can form a divalent organic group[)];
• X represents an oxygen atom;
• Y represents a substituent;
• q represents any integer of 0 to 3;
• n represents 0 or 1;
• and
• m represents 0 or 1.