Streptomyces endophyte compositions and methods for improved agronomic traits in plants

A method of increasing abundance of one or more arbuscular mycorrhizal fungi in roots of a plant under water-stressed conditions, comprising treating a plant reproductive element with a formulation comprising an effective amount of a Streptomyces endophyte that is heterologous to the plant reproductive element, wherein the Streptomyces endophyte comprises

• a 16S polynucleotide sequence having at least 97% identity to SEQ ID NO 2 and at least 3 polynucleotides that encode an arabinose transporter protein;
• wherein the effective amount is effective to increase abundance of one or more arbuscular mycorrhizal fungi in roots of a plant grown from the treated reproductive element under water-stressed conditions, as compared to an isoline plant grown from a plant reproductive element not treated with the Streptomyces endophyte.