pH of Water and Tank Mixture Comprising Growth Regulator and Agrochemicals in Wheat

Aims: The aim of this study was to evaluate, under field conditions, the effect of lowering previously the of pH of the water used in the tank mixture spraying of trinexapac-ethyl, (imidacloprid + beta-cyfluthrin), (trifloxystrobin + tebuconazole) and iodosulfuron-methyl on plant height, agronomic traits and phytotoxicity caused to wheat plants.

Study Design: The study used a randomized block design with four replications. The treatments were distributed into a 2 x 13 factorial arrangement.

Place and Duration of Study: A field experiment was carried out during the 2016 growing season, from July, 22 to December, 5. The experiment was conducted at experimental farm of Santa Catarina State University, Lages, Santa Catarina state, Brazil.

Methods: The treatments consisted of the presence and absence of a pH reducer (phosphoric acid) and thirteen mixtures corresponding to different combinations of the trinexapac-ethyl growth regulator and iodosulfuron-methyl herbicide, (trifloxystrobin + tebuconazole) fungicide and the (imidacloprid + beta-cyfluthrin) insecticide.

Results: The use of low pH water did not increase phytotoxicity caused by the mixtures of trinexapac-ethyl, (imidacloprid + beta-cyfluthrin), (trifloxystrobin + tebuconazole) and iodosulfuron-methyl. There was no effect of the pH reducer and the mixtures on plant lodging, yield components and wheat grain yield.

Conclusion: The use of a spray solution at pH 4.0 enhances the effect of trinexapac-ethyl in decreasing plant height, but without changing the productive potential of wheat.