My research group focuses on the population biology of plant pathogenic organisms and the relationship between population genetics and epidemiology.  We use molecular tools to study population-level evolutionary processes, mainly in plant-pathogenic fungi, and link them to traits of interest such as pathogenicity, virulence or fungicide resistance. Our ultimate goal is to understand how these traits arise and evolve and move among pathogen populations.

I am mainly interested in soilborne pathogens, in particular fungi that cause vascular wilts, such as Verticillium species and Fusarium oxysporum formae speciales. Verticillium dahliae causes Verticillium wilt of hundreds of herbaceous and woody crops. Recent studies indicate that some components of the pathogen populations appear to be adapted or even specialized to cause disease in particular crops, thus populations may be host adapted. We are developing molecular tools to study host adaptation of V. dahliae populations. Another soilborne fungal system that my lab is studying is the  Fusarium oxysporum f. sp. ciceris/ Chickpea pathosystem. My previous research indicated that the evolution of pathogenic races in F. oxysporum f. sp. ciceris has followed a stepwise mutation model. We are now trying to validate that model through a collaboration with Prof. Rafael Jimenez-Diaz and his group at the University of Cordoba, and the Institute of Sustainable Agriculture (IAS-CSIC) in Cordoba, Spain.

My second line of research involves foliar pathogens. In a collaborative effort with Dr. James Travis at the Fruit Research Center, PSU, we are investigating populations of Venturia inaequalis, the causal agent of Apple Scab. We are using molecular markers (microsatellites) to estimate genetic diversity in this pathogen, understand movement of populations and correlate this with fungicide resistance and virulence.

Teaching: PPATH 505: Fundamentals of Phytopathology

Find more in http://zeus.plmsc.psu.edu/~jimenez/

Landa, B. B., Navas-Cortes, J. A., Jimenez-Gasco, M. M., Katan,  J., Retig, B., and Jimenez-Díaz, R. M. 2006. Temperature response of chickpea cultivars to races of Fusarium oxysporum f. sp. ciceris , causal agent of Fusarium wilt. Plant Disease 90:365-374.

Jimenez-Gasco, M. M., Navas-Cortes, J. A., and Jimenez-Diaz,  R. M. 2004. The Fusarium oxysporum f. sp. ciceris / Cicer arietinum pathosystem: a case study of the evolution of plant-pathogenic fungi into races and pathotypes. International Microbiology 7: 95-104.

Geiser, D. M., Jimenez-Gasco, M. M., Kang, S., Makalowska, I. , Veerarahavan, N., Ward, T. J. Zhang, N., Kuldau, G. A., and O'Donnell, K. 2004. FUSARIUM-ID v.1.0: A DNA sequence database for identifying Fusarium. European Journal of Plant Pathology 110: 473-479.

Jimenez-Gasco, M. M., Milgroom, M. G., and Jimenez-Diaz,  R. M. 2004. Stepwise evolution of races in Fusarium oxysporum f. sp. ciceris inferred from fingerprinting with repetitive DNA sequences.  Phytopathology 94: 228-235.

Jimenez-Gasco, M. M., Jimenez-Diaz, R. M. 2003. Development of a specific PCR-based assay for the identification of Fusarium oxysporum f. sp. ciceris and its pathogenic races 0, 1A, 5, and 6. Phytopathology 93: 200-209.

Jimenez-Gasco, M. M., Milgroom, M. G., and Jimenez-Diaz,  R. M. 2002. Gene genealogies support Fusarium oxysporum f. sp. ciceris as a monophyletic group. Plant Pathology 51: 72-77. 

Jimenez-Gasco, M. M., Perez-Artes, E., Jimenez-Diaz, R. M. 2001. Identification of pathogenic races 0, 1B/C, 5, and 6 of Fusarium oxysporum f. sp ciceris with random amplified polymorphic DNA (RAPD). European Journal of Plant Pathology 107: 237-248.