Patricia McManus


Phone: 608-265-2047

376 Russell Labs
1630 Linden Dr
Madison, WI 53706


B.S. 1986 University of Wisconsin-Madison, Botany
M.S. 1988 Michigan State University, Botany and Plant Pathology
Ph.D. 1994 Michigan State University, Botany and Plant Pathology

Research Interests

My research and extension programs are focused on practical problems that affect the profitability and sustainability of growing fruit crops. Wisconsin leads the nation in cranberry production; some other fruit crops grown here include apple, tart cherry, grape, strawberry, raspberry, and blueberry. The nature of our work depends largely on the current and anticipated needs of fruit growers in Wisconsin and elsewhere. We employ a variety of cultural, physiological, microscopic, and molecular techniques, and conduct research in the laboratory, greenhouse, and field.

One line of cranberry research focuses on the biology of Tobacco streak virus and Blueberry shock virus in commercial cranberry plantings, and the impact of these viruses on cranberry production. Once we know more about how these viruses spread and how disease develops in the field, we will be better able to advise growers on managing viruses.

Other cranberry research is focused on the management of fruit rot, a disease complex of at least eight fungal species. In some cases, fruit rot cannot be well controlled with fungicide, suggesting a possible role for other microbes in the disease complex. We are using culture-dependent and culture-independent methods to explore the possible role of bacteria, yeasts, and other microbes in causing fruit rot. Early results suggest that yeasts are potential pathogens. Yeasts are ubiquitous microbes, but they rarely have been considered plant pathogens.

We are collaborators on the Northern Grapes Project, a multi-state effort focused on grape and wine production in the northern US. Our role is to evaluate the so-called “cold-climate cultivars” for disease susceptibility and for sensitivity to copper- and sulfur-based fungicides. Our long-term goal is to develop economically sound integrated pest management practices for northern growers.
My extension efforts are focused on educating growers and crop consultants on: (i) identifying disease problems; (ii) managing diseases in an economically and environmentally sound manner; and (iii) managing fungicide/bactericide resistance. Extension education is conducted in large meetings of hundreds of people, in small groups, and one-on-one on the farm.

Recent Publications

Thomas-Sharma, S., Wells-Hansen, L., Page, R., Kartanos, V., Saalua-Rojas, E. Lockhart, B.E.L., and McManus, P.S. 2018. Characterization of Blueberry shock virus, an emerging Ilarvirus in cranberry. Plant Disease 102:91-97.

Jones, D.S., and McManus, P.S. 2017. Distinctive symptoms and signs of downy mildew on cold-climate wine grape cultivars. Plant Health Progress 18:192-195.

Jones, D.S., and McManus, P.S. 2017. Susceptibility of cold-climate wine grape cultivars to downy mildew, powdery mildew, and black rot. Plant Disease 101:1077-1085.

Wells-Hansen, L.D. and McManus, P.S. 2017. Year-to-year incidence of cranberry fruit rot and persistence of fungal pathogens. Plant Health Progress 18:114-119.

McManus, P.S., Kartanos, V., and Stasiak, M. 2017. Sensitivity of cold-climate wine grape cultivars to copper, sulfur, and difenoconazole fungicides. Crop Protection 92:122-130.

Wells-Hansen, L.D., and McManus, P.S. 2016. Recovery of cranberry plants infected with Tobacco streak virus and incidence and distribution of TSV in the field. Plant Disease 100:2257-2265.

Wells-Hansen, L.D., Polashock, J.J., Vorsa, N., Lockhart, B.E.L., and McManus, P.S. 2016. Identification of Tobacco streak virus in cranberry and the association of TSV with berry scarring. Plant Disease 100:696-703.

McManus, P.S. 2014. Does a drop in the bucket make a splash? Assessing the impact of antibiotic use on plants. Current Opinion in Microbiology 19: 76-82.

Wells, L.D., Perry, R.S., and McManus, P.S. 2014. Fungicide efficacy and specificity toward fungi in the cranberry fruit rot disease complex. Plant Health Progress doi: 10.1094/PHP-RS-13-0024.

Batzer, J. C., McManus, P. S., and Gleason, M. L. 2013. Fungicide spray volume and pruning impact performance of a warning system for sooty blotch and flyspeck on apple. Plant Health Progress doi:10.1094/PHP-2013-0930-01-RS.

Shade, A., Klimowicz, A., Spear, R. Linske, M. Donato, J., Hogan, C., McManus, P., and Handelsman, J. 2013. Streptomycin application has no detectable effect on bacterial community structure in apple orchard soil. Applied and Environmental Microbiology 79: 6617-6625.

Wells, L.D., and McManus, P.S. 2013. Effects of simulated hail events and subsequent fungicide applications on cranberry fruit rot incidence and yield. Plant Disease 97: 1207-1211.

Wells, L.D., and McManus, P.S. 2013. A photographic diagnostic guide for identification of the principal cranberry fruit rot pathogens. Plant Health Progress doi: 10.1094/PHP-2013-0729-01DG.

A. Shade, P.S. McManus, and J. Handelsman. 2013. Unexpected diversity during community succession in the apple flower microbiomemBio 4(2):e00602-12. doi:10.1128/mBio.00602-12.

A. Shade, C.S. Hogan, Klimowicz, A.K., Linske, M., McManus, P.S., and Handelsman, J. 2012. Culturing captures members of the soil rare biosphere. Environmental Microbiology 14:2247-2252

Yashiro, E., and McManus, P.S. 2012. Effect of streptomycin treatment on bacterial community structure in the apple phyllospherePLoS One 7(5) e37131.

Gruber, B.R., Kruger, E.L., and McManus, P.S. 2012. Effects of cherry leaf spot on photosynthesis in tart cherry ‘Montmorency’ foliage. Phytopathology 102:656-661.

Yashiro, E., Spear, R.N., and McManus, P.S. 2011. Culture-dependent and culture-independent assessment of bacteria in the apple phyllosphere. Journal of Applied Microbiology 110:1284-1296.

Gleason, M.L.,Batzer, J.C., Sun, G., Zhang, R., Díaz Arias, M.M., Sutton, T.B., Crous, P.W., Ivanović, M., McManus, P.S., Cooley, D.R., Mayr, U., Weber, R.W.S., Yoder, K.S., Del Ponte, E.M., Biggs, A.R., and Oertel, B. 2011. A new view of sooty blotch and flyspeck. Plant Disease 95:368-383.

Donato, J.J., Moe, L.A., Converse, B.J., Smart, K.D. Berklein, F.C., McManus, P.S., and Handelsman, J. 2010. Metagenomics reveals antibiotic resistance genes encoding predicted bifunctional proteins in apple orchard soil. Applied and Environmental Microbiology 76:4396-4401.

Batzer, J.C., Rincon, S.H., Mueller, D.S., Petersen, B.J., LeCorronc, F., McManus, P.S., Dixon, P.M., and Gleason, M.L. 2010. Effect of temperature and nutrient concentration on the growth of six species of sooty blotch and flyspeck fungi. Phytopathologia Mediterranea 49:3-10.

Gruber, B.R., Davies, L.R.R., and McManus, P.S. 2010. A copper-based fungicide has minimal effects on tart cherry fruit quantity and quality. HortScience 45:48-53.