
Keywords: PGR، تنظیم کننده رشد گیاه; Grass seed crop production; Schedonorus arundinaceus (Shreb.) Dumort. seed yield; Trinexapac-ethyl; LodgingTE, trinexapac-ethyl; HI, harvest index; PGR, plant growth regulator; BBCH, Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie