Department of Plant Plathology and Microbiology @ UCR

Research Specialization - plant bacteriology. My research spans both fundamental and practical research on plant pathogenic bacteria, as well as research on beneficial bacteria for use in biological control of plant diseases. We are conducting basic research in comparative and functional genomics of the pathogen causing Pierce's disease of grapevine (Xylella fastidiosa). Our goal is to identify key virulence factors through construction of specific mutations in the bacterial genome. Such mutants will also be tested for competitive displacement of pathogenic strains as a means of biological control of Pierce's disease in grapevine. We are also continuing our long-term research on the molecular genetics and biochemistry of bacterial resistance to bactericides used in agriculture, as well as research on the identification of genes in beneficial bacteria that are specifically expressed during parasitism of plant pathogenic fungi. We also conduct practical research on the etiology of new bacterial disease outbreaks, on diagnostic methods, and on disease control strategies.

Costa, H. S., E. Raetz, T. Pinckard, C. Gispert, R. Hernandez-Martinez, C. K. Dumenyo, and D. A. Cooksey. 2004. Plant hosts of Xylella fastidiosa in and near southern California Vineyards. Plant Dis., 88:1255-1261.
Voloudakis, A. E., T. M. Reignier, and D. A. Cooksey. 2005. Regulation of copper resistance in Xanthomonas axonopodis pv. vesicatoria. Appl. Environ. Microbiol., 71:782-789.
Kuzina, L. V., T. A. Miller, and D. A. Cooksey. 2006. In vitro activities of antibiotics and antimicrobial peptides against the plant pathogenic bacterium Xylella fastidiosa. Lett. Appl. Microbiol., 42:514-520.
Hernandez-Martinez, R., T. Pinckard, H. S. Costa, D. A. Cooksey, and F. P. Wong. 2006. Characterization of mulberry leaf scorch strains isolated in Southern California, discovery of a new Xylella fastidiosa strain infecting shade trees in the urban landscape. Plant Dis., 90:1143-1149.
Costa, H. S., A. Guzman, R. Hernandez-Martinez, C. Gispert, and D. A. Cooksey. 2006. Detection and differentiation of Xylella fastidiosa strains acquired and retained by glassy-winged sharpshooters using a mixture of strain-specific primer sets. J. Econ. Entomol., 99:1058-1064.
Hernandez-Martinez, R., H. S. Costa, C. K. Dumenyo, and D. A. Cooksey. 2006. Differentiation of strains of Xylella fastidiosa infecting grape, almonds and oleander using a multiprimer PCR assay. Plant Dis., 90:1382-1388.
Yang, S., Q. Zhang, J. Guo, A. O. Charkowski, B. R. Glick, A. M. Ibekwe, D. A. Cooksey, and C.-H. Yang. 2007. Global effect of Indole-3-acetic acid (IAA) biosynthesis on multiple virulence factors of Erwinia chrysanthemi 3937. Appl. Environ. Microbiol. 73: 1079-1088.
Bi, J. L., C. K. Dumenyo, R. Hernandez-Martinez, D. A. Cooksey, and N. C. Toscano. 2007. Effect of host plant xylem fluid on growth, aggregation and attachment of Xylella fastidiosa. J. Chem. Ecol., 33: 493-500.
S.-J. Ahn, C.-H. Yang, and D. A. Cooksey. 2007. Pseudomonas putida 06909 genes expressed during colonization on mycelial surfaces and phenotypic characterization of mutants. J. Appl. Microbiol., 103:120-132.
Hernandez-Martinez, R., K. de la Cerda, H. S. Costa, D. A. Cooksey, and F. P. Wong. 2007. Phylogenetic relationships of Xylella fastidiosa strains isolated from landscape ornamentals in southern California. Phytopathology, 97:857-864.
Shi, X.Y., C. K. Dumenyo, R. Hernandez-Martinez, H. Azad, and D. A. Cooksey. 2007. Characterization of regulatory pathways in Xylella fastidiosa: genes and phenotypes controlled by algU. Appl. Environ. Microbiol. 73:6748-6756.
Shi, X.Y., and D. A. Cooksey. 2009. Identification of hrpL up-regulated genes of Dickeya dadantii. Eur. J. Plant Pathol. 124:105-116.
Shi, X. Y., C. K. Dumenyo, R. Hernandez-Martinez, H. Azad, and D. A. Cooksey. 2009. Characterization of regulatory pathways in Xylella fastidiosa: genes and phenotypes controlled by gacA. Appl Environ. Microbiol., 75:2275-2283.