Expertise:

Dr. Marra has expertise in mycology, fungal genetics, population biology, evolution, and molecular biology.  His research focuses on forest pathogens from various perspectives, including population biology, ecology, and mating system evolution.  Techniques utlilized in his laboratory include culturing, microscopic analysis, and molecular biology.  Population genetic studies employ several types of molecular markers, including microsatellites, amplified-fragment-length-polymorphisms (AFLPs), and single-strand-conformational-polymorphisms (SSCPs), to study genetic structure and mating patterns in natural populations.  Dr. Marra, in collaboration with Dr. Sharon Douglas, has been instrumental in establishing the Molecular Plant Diagnostics Laboratory, in which state-of-the-art molecular technologies, including real-time PCR, are utilized to aid in the rapid identification of plant diseases. 

Education:

B.S., State University of New York at Binghamton (1990); Biology/Russian

Ph.D., Cornell University (1998); Plant Pathology/Mycology

Career History:

Postdoctoral Associate with Dr. Thomas G. Mitchell, Department of Molecular Genetics, Duke University Medical Center, and Dr. Rytas Vilgalys, Department of Biology, Duke University, 2001-2004

Postdoctoral Associate with Dr. John Jaenike, Department of Ecology and Evolutionary Biology, University of Arizona, 1999-2001

Station Career:

Assistant Agricultural Scientist II, 2004-

Past Research:

Dr. Marra’s dissertation research investigated the mating system of the chestnut blight pathogen, Cryphonectria parasitica, at both molecular and population levels of study.  He has also looked at population structure in C. parasitica populations, and how site ecology plays a role in genetic structure of populations.  Dr. Marra did his postdoctoral research on the human pathogenic fungus, Cryptococcus neoformans, a basidiomycete yeast that causes cryptococcal meningitis, for which he developed a genetic linkage map.  He also contributed to the C. neoformans whole genome sequencing project. 

Current Research:

Dr. Marra is currently working on Neonectria ditissima, the ascomycete fungus that causes target canker in birch (Betula spp.) trees.  He has been developing a suite of molecular genetic markers with which he is investigating genetic structure in natural populations of the fungus, particularly as it correlates with host density and site ecology.  Dr. Marra is also collaborating with Dr. DeWei Li on Stachybotrys systematics, and with Dr. Wade Elmer on the systematics of the Fusarium species associated Sudden Wetland Dieback in coastal salt marshes. 

Selected publications available from author, Robert.Marra@po.state.ct.us

·      Marra, R. E., and S. M. Douglas.  2005.  Phytophthora ramorum:  a new threat to Connecticut’s forests and landscapes.  Frontiers of Plant Science 55(2): 2-4. 

·      Marra, R. E., J. C. Huang, K. Nielsen, R. V. Vilgalys, and T. G. Mitchell.  2004. A Genetic Map of Cryptococcus neoformans, var. neoformans Serotype D (Filobasidiella neoformans).  Genetics 167: 619-631.

·    Marra, R. E., and  M. G. Milgroom.  2004.  Mixed mating in natural populations of the chestnut blight fungus, Cryphonectria parasitica. Heredity 93: 189-195.   

·   Marra, R. E., and M. G.Milgroom.  2001.  The mating system of the fungus Cryphonectria parasitica: selfing and self-incompatibility.  Heredity 86(2): 134-143. 

·    Marra, R. E., and M. G. Milgroom.  1999.  PCR amplification of the mating-type idiomorphs in Cryphonectria parasitica.  Molecular Ecology 8: 1947-1950. 

·     Loftus, B. J., E. Fung, P. Roncaglia, D. Rowley, P. Amedeo, D. Bruno, J. Vamathevan, M. Miranda, I. J. Anderson, J. A. Fraser, J. E. Allen, I. E. Bosdet, M. R. Brent, R. Chiu, T. L. Doering, M. J. Donlin, Cl A. D’Souza, D. S. Fox, V. Grinberg, J. Fu, M. Fukushima, B. J. Haas, J. C. Huang, G. Janbon, S. J. M. Jones, H. L. Koo, M. I. Krzywinski, J. K. Kwon-Chung, K. B. Lengeler, R. Maiti, M. A. Marra, R. E. Marra, C. A. Mathewson, T. G. Mitchell, M. Pertea, F. R. Riggs, S. L. Salzberg, J. E. Schein, A. Shvartsbeyn, H. Shin, M Shumway, C. A. Specht, B. B. Suh, A. Tenney, T. R. Utterback, B. L. Wickes, J. R. Wortman, N. H. Wye, J. W. Kronstad, J. K. Lodge, J. Heitman, R. W. Davis, C. M. Fraser, R. W. Hyman.  2005.  The Genome of the Basidiomycetous Yeast and Human Pathogen Cryptococcus neoformans.  Science 307: 1321-1324. 

·     Litvintseva, A. P., R. E. Marra, K. Nielsen, J. Heitman, R. Vilgalys, T. G. Mitchell, 2003. Evidence of sexual recombination among Cryptococcus neoformans Serotype A Isolates in Sub-Saharan Africa. Eukaryotic Cell 2: 1162-1168.

·     McGuire, I. C., R. E. Marra, and M. G. Milgroom.  2004.  Mating-type heterokaryosis and selfing in Cryphonectria parasitica.  Fungal Genetics and Biology 41: 521-533. 

·     McGuire, I. C., R. E. Marra, B. G. Turgeon, and M. G. Milgroom.  2002.  Analysis of mating-type genes in the chestnut blight fungus Cryphonectria parasitica.  Fungal Genetics and Biology 34(2): 131-144. 

·      Nielsen K., R. E. Marra, F. Hagen,  T. Boekhout, T. G. Mitchell, G. M. Cox, and J. Heitman. 2005.  Interaction between genetic background and the mating type locus in Cryptococcus neoformans virulence potential.  Genetics 171: 975-983.