Inhibition Responses of Mepiquat Chloride on Growth of Creeping Bentgrass

Hyeok-Jae  Heo1   Eun-Hye  Park2   Jin-Ho  Kim1   Jeong-Ho  Youn3   Young-Sun  Kim2,4   Geung-Joo  Lee5,*   

1School of Ecology & Environmental System (Major in Plant Resource Environment), Kyungpook National University, Daegu 41566, Korea
2Division of Life & Environmental Science (Horticulture Major), College of Natural and Life Sciences, Daegu University, Gyeongsan 38453, Korea
3Hanul Co., Ltd., Hapcheon 13206, Korea
4Institute of Basic Science, Daegu University, Gyeongsan 38453, Korea
5Department of Horticulture and Department of Smart Agriculture Systems, Chungnam National University, Daejeon 34134, Korea


Mepiquat chloride (MC) was a plant growth regulator of quarternary ammonium family acting on inhibiting gibberellin biosynthesis. This study was conducted to evaluate the inhibition effect of MC on the growth of creeping bentgrass (Agrostis palustris) by investigating visual quality indices, shoot length and clipping yield. As compared with control, turf color index, chlorophyll index and visual quality in the creeping bentgrass treated with MC was not significantly different, meaning those doses dis not interfere creeping bentgrass growth. The shoot length of MC treatments was decreased by 20-23% on 28 day after treatment than that of control and clipping yield by 39-56%. Compared with another growth retardant, the reference trinexapac-ethyl (RT), clipping yield of MC treatments were not significantly different, but retardant effect was more evident. The applying amount of MC was correlated with clipping yield negatively (P<0.05). These results indicated that the MC application was retarded the shoot growth of creeping bentgrass and decreased the clipping yield, and that MC might be another choice of growth retardant applying to creeping bentgrass.

Figures & Tables

Fig. 1. Clipping yield of creeping bentgrass after application of mepiquat chloride in pot experiment. RT: Reference trinexapac-ethyl; HM: Half dose of Mepiquat chloride (MC); RM: Recommendation dose of MC; DM: Double dose of MC. z Treatments were as follows; Control (non-treatment of plant growth regulator), RT (trinexapac ethyl [TE] 0.01 a.i.·g·m; 2,500 fold dilution), HM (MC 0.033 a.i.·g·m; 2,000 fold dilution), RM (MC 0.066 a.i.·g·m; 1,000 fold dilution), DM (MC 0.132 a.i.·g·m; 500 fold dilution). TE and MCs were applied on creeping bentgrass on June 11 in 2019. Error bars indicates standard deviation and different letters indicates significant different at ≤0.05 level according to Duncan’s multiple range test.