Journal Article Research Support, Non-U.S. Gov't Plant Proteins Populus 451W47IQ8X Antioxidant enzyme Cambium Demographic history Drought Gene regulatory network (GRN) Indoleacetic Acids Membrane Transport Proteins Molecular mechanisms PIN family PdPRP Populus deltoids Receptor-like protein kinase Salix psammophila Salt Secondary wall formation Sodium Chloride Transgene Vascular growth auxin dual regulation endoplasmic reticulum functional module genome-wide association study growth regulating factor (GRF) heat stress (HS)