Abstract: A diazotrophic microbe is genetically modified to secrete a nitrogen-containing compound in an amount greater than a comparable control diazotrophic microbe. In one or more embodiments, the diazotrophic microbe is an endophyte. In one or more embodiments, the genetic modification includes a deletion or disruption of a gene involved in import or export of nitrogen-containing compounds. In some of these embodiments, the genetic modification includes a deletion or disruption of a gene encoding a gene product that transports ammonium into the cell, recycles lost ammonium back into the cell, and/or transports ammonia out of the cell. In one or more embodiments, the amount of secreted nitrogen-containing compound is effective to support the growth of a non-diazotroph in co-culture.

Abstract: This invention relates to the identification of a gene involved in the gibberellin signal transduction pathway. Mutations to this gene mimic the effect of gibberellin treatment and transgenic plants expressing the gene correct a spindly phenotype. Methods are disclosed for isolating and using the gene from a variety of plants.