Ascend® contains the plant growth regulators cytokinin (0.09%), gibberellic acid (0.03%) and indole butyric acid (0.045%). It can be applied on the seed, in-furrow at planting, 2x2 or 3 inches below the seed at planting, at the 3-4 leaf stage and/or at the 8-11 leaf stage.
We tested the plant growth regulator Ascend® by applying it to an adapted hybrid and comparing it to the same hybrid left untreated at eleven locations in Wisconsin. Applications were made at the labelled rate and timing of 3.2 oz/A at V3-V4. Locations that exhibited significant drought stress included Chippewa Falls, Lancaster, Janesville, Arlington and Fond du Lac. Hancock was an irrigated site.
At seven of eleven locations there was no statistical difference when using Ascend®. At three of eleven locations, the untreated plots yielded more than plots treated with Ascend®. At one of eleven locations, Ascend® treated plots yielded more than untreated plots.
Table 1. Corn grain yield response of an adapted corn hybrid treated with Ascend® plant growth regulator to an untreated check during 2012.
At none of the sites that had significant drought stress during the growing season did Ascend® stimulate higher yields. Across all locations there was no statistical difference between corn treated with Ascend® (196 bu/A) and untreated corn (200 bu/A).