Abstract: This invention provides cyanobacteria as an alternative source of ahas and pds genes for plant transformations and for selectable markers. In particular, it provides for cyanobacteria, for example, Synechocystis, as a source of genes encoding herbicide insensitive proteins, and elements of genes for control of expression in plastids. Nucleic acid fragments, both the acetolactate synthase (ahas) large subunit and the ahas small subunit, were found to provide herbicide resistance. Also, the present invention provides novel Synechocystis mutant phytoene desaturase (PDS) gene conferring resistance to 4?-fluoro-6[(alpha,alpha,alpha,-trifluoro-m-tolyl)oxy]-picolinamide, a bleaching herbicide. The present invention provides improvements to method involving cyanobacteria for the screening of compounds, including a new high-through-put protocol that is a rapid and cost effective way to identify target site genes.

Abstract: The present invention provides novel polynucleotides encoding plant Na+/H+ antiporter polypeptides, fragments and homologs thereof. Also provided are vectors, host cells, antibodies, and recombinant methods for producing said polypeptides. The invention further relates to methods of applying these novel plants polypeptides to the identification, prevention, and/or conferment of resistence to various plant diseases and/or disorders, particularly those associated with modulating environmental stress responses, such as drought and salt tolerance.

Abstract: A transgenic plant transformed by an Ion Transporter Stress-Related Polypeptide (ITSRP) coding nucleic acid, wherein expression of the nucleic acid sequence in the plant results in increased tolerance to environmental stress as compared to a wild type variety of the plant. Also provided are agricultural products, including seeds, produced by the transgenic plants. Also provided are isolated ITSRPs, and isolated nucleic acid coding ITSRPs, and vectors and host cells containing the latter.

Abstract: A transgenic plant transformed by a Protein Phosphatase Stress-Related Polypeptide (PPSRP) coding nucleic acid, wherein expression or repression of the nucleic acid sequence in the plant results in increased tolerance to environmental stress as compared to a wild type variety of the plant. Also provided are agricultural products, including seeds, produced by the transgenic plants. Also provided are isolated PPSRPs, and isolated nucleic acid coding PPSRPs, and vectors and host cells containing the latter.