Modulation of halotropic growth in rough bluegrass (Poa trivialis L.) by flavonoids and light

•Poa trivialis L. exhibited halotropism when exposed to NaCl concentration gradients.•Halotropism was enhanced in plants treated with blue light (BL).•Plants treated with red light or kept in darkness did not exhibit halotropic growth.•Significant quantities of flavonoids were only quantified in BL treated roots.•We provide evidence that BL and flavonoids are involved in regulating halotropism.