SEAISLE 1 AND PLANT GROWTH REGULATORS

PGR'S Plant growth regulators can be used on SeaIsle 1, but little data has been published. Some golf course superintendents have tried trinexa pac-ethyl (Primo) with success at 0.09 ai/acre rate. Cutless (flurprimidol) at 0.75 ai/acre has been used in conjunction with Prograss to control bermudagrass in paspalum, but phytotoxicity occurs on paspalum when temperatures at <70 F or >85 F. Never apply PGRs to grasses under stress. Read the label for specific use instructions.
BRAND/MANUFACTURER	ACTIVE INGREDIENT	MODE OF ACTION	CLASS
Primo/Novartis	Trinexapac-ethyl	Interferes with production of gibberelins which influence cell elongation, chilling tolerance, and photoperiod response. Foliar absorption.	A
Triple Play/Lesco	Trinexapac-ethyl		A
Cutless/Lesco	Flurprimidol	Interferes with gibberellin biosynthesis, but early in the production pathway. Provides 5-6 weeks of growth regulation, but has greater risk of phytotoxicity problems.	B
TGR(Parlay)/Scotts	Paclobutrazol		B
Embark/PBI-Gordon	Myclobutanil	Cell division (mitotic) inhibitor. 3 - 4 weeks growth cessation. Seed head suppression. May cause grass discoloration. Foliar absorption.	C
Limit	Amidochlor		C