PROBLEM TO BE SOLVED: To provide a plant growth regulator that is superior in the effect to promote root growth.SOLUTION: A plant growth regulator is obtained by a combination of phenyllactic acid or salt thereof and methionine or salt thereof.COPYRIGHT: (C)2014,JPO&INPIT【課題】根の発達を促進する効果に優れた植物成長調整剤の提供。【解決手段】フェニル乳酸又はその塩とメチオニン又はその塩とを組み合わせてなる植物成長調整剤。【選択図】なし