The present disclosure provides compositions and methods for altering gibberellin (GA) content in corn or other cereal plants. Methods and compositions are also provided for altering the expression of genes related to gibberellin biosynthesis through suppression, mutagenesis and/or editing of specific subtypes of GA20 or GA3 oxidase genes. Modified plant cells and plants having a suppression element or mutation reducing the expression or activity of a GA oxidase gene are further provided comprising reduced gibberellin levels and improved characteristics, such as reduced plant height and increased lodging resistance, but without off-types.