Possibility of joint application of herbicides with growth regulators in spring barley

In 2015–2016 field experiments were carried out to evaluate the possibility of the mixtures of herbicides Starane 250 EC (fluroxypyr) and Dragon 450 WG (florasulam + aminopyralide) with growth regulators Moddus 250 EC (trineksapac-ethyl) and Manipulator SL (chlormequat chloride) application in spring barley. Each of them was used in two terms: 1. in stage of tillering (BBCH 25–26), 2. in stage of 1-st node (BBCH 31) of spring barley. Weed control effect of the examined mixtures depended on weed infestation and term of spraying. Moderately sensitive to the tested herbicides weed species were controlled in low degree when spraying was performed at the growth stage BBCH 31. The investigated mixtures reduced height of spring barley plants markedly where the best results were noted for the mixture Dragon 450 WG + Manipulator SL applied in growth stage of tillering. The examined mixtures contributed to significant grain yield increase of spring barley. The lowest yield increase as compared to control was achieved where herbicide Starane 250 EC with growth regulators was applied in the BBCH 31 stage. It was due to poor weed control at these objects.