Overexpression of an AP2/ERF family gene, BpERF13, in birch enhances cold tolerance through upregulating CBF genes and mitigating reactive oxygen species.

•A birch ERF transcription factor, BpERF13, which positively responds and regulates cold stress, was cloned and functionally characterized.•Transgenic lines overexpressing BpERF13 exhibited normal phenotypes except for a significantly augmented tolerance to cold stress.•BpERF13 augmented cold tolerance in transgenic lines through upregulating two CBF genes and four reactive oxygen species scavenging genes.