Meet the 2023 Graduates

Graduate Program

Terry Jarianna Torres Cruz

Ph.D.,  Plant Pathology and Biogeochemistry

Cruz's thesis is titled "From Fungus to Flower: Pseudoflower Formation by a Novel Fusarium Species from Guyana and Its Dispersal by Insects."

Her dissertation focused on better describing the interactions between a grass endemic to South America (Xyris surinamensis) and a fungus (Fusariumxyrophilum) that mimics the flower of this grass. The study assessed distribution of F. xyrophilum on its host and its potential to affect insect visitation, while evaluating bacterial and fungal microbiome differences between infected and uninfected tissues.

Terry Jarianna Torres Cruz received the following awards during her graduate career at Penn State:

• Lester P. Nichols Memorial Award. 2022. Penn State College of Agricultural Sciences.
• Student Leader Scholarship. 2021. Penn State Student Affairs.
• Indigo Ag Phytobiomes Fellowship. 2021.Penn State Microbiome Center.
• Lewis and Clark Fund for Exploration and Field Research. 2021. American Philosophical Society.
• James F & Marilyn Tammen Memorial Endowment to support travel to Guyana.2021. Penn State PPEM.
•  Ardeth and Norman Frisbey International Graduate Student Award. 2020. Penn State Global Programs.
•  Popp Endowment Award.2020. Penn State PPEM.
• Clark T Rogerson Research Award to support field trip to Guyana. 2019. Mycological Society of America.
• Wilderness First Aid Training Grant. 2019. Penn State Global Safety Office.
• Black Research Fund Travel Award. 2019. Penn State College of Agricultural Sciences.
• Jose de la Torre Scholarship. 2018. Penn State College of Agricultural Sciences.
• “Give a DAWG a bone” Award for microbiome sequencing. Penn State Microbiome Center.
• Larry J. Jordan Memorial Endowment to support field trip to Guyana. 2018. Penn State PPEM.

Leadership Roles:

• Student Representative in the Mycological Society of America.
• Student Representative in the Nominations Committee (2021–2022) and International Committee (2017–2020).
• Penn State International Student Orientation Leader (2018–2022).
• Penn State Plant Pathology Association – President (2020–2021).
•  Penn State’s Graduate School Alumni Society Board of Directors (2020–2021)
• Events coordinator. Penn State PPEM Diversity, Equity, and Inclusion Committee (2019–2021) Chair and co-founder.
• Posters Judge for International Agriculture class (INTAG100) at Penn State during Spring and Fall 2019-2021.
• Penn State SACNAS Chapter (2019–2020) Society for Advancement of Chicanos/Hispanics and Native Americans in Science (SACNAS).
• Healthy Penn State Ambassador (2019) Health, Promotion, and Wellness.
• Penn State PPEM Seminar Committee (2018–2020) Student representative.
• Penn State Graduate and Professional Student Association (GPSA) (2018–2020)
• College of Agricultural Sciences Delegate and Speaker of the Assembly (2019–2020) and At-large Delegate (2018-2019).
• Served on GPSA Community Outreach and Programming Committees.
• Graduate Posters Judge. Penn State Graduate School 33rd Annual Graduate Exhibition, March 2018.

Ryan Guo

M.S., Plant Pathology; Phytopathology

Ryan Guo has accepted a position as a Research Scientist with Sylvan Inc.

Guo's thesis is titled "Working Towards Morel Cultivation in the Northeastern United States."

His project aimed to grow morels both indoors and outdoors at State College, PA. From 2019 to 2022, he tested the yield potential of Morchella importuna with both mating-types indoors and outdoors, and M. importuna fruited both indoors and outdoors with MAT 1-1 or MAT 1-2 individually as well as mixed.

When asked about insight for prospective students, Guo responded, "'If you really wanna do this with your life, you have to believe that you are necessary, and you are.' - Will Emerson from the movie Margin Call"

Constanza Bartolomeo Koninckx

M.S., Plant Pathology and Environmental Microbiology

Koninckx's thesis is titled "Development of Phyllosphere Suppressive Communities Towards Xanthomonas perforans and their Potential Applications as a Biological Control Against Bacterial Spot of Tomato"

She concentrated mainly on the study of phyllosphere microbial communities on tomato plants. She focused on developing a phyllosphere community makeup that resulted in bacterial spot disease suppression on tomato plants. She explored potential applications of those suppressive communities as a biological control of bacterial spot disease on tomatoes.

Leadership Roles:

• Social Committee representative Vice president of the Plant Pathology Association
• Member of Gamma Sigma Delta Honor Society of Agriculture, in recognition of high scholarship, outstanding achievement or service.

Andrew Miles

M.S., Plant Pathology

Miles' thesis is titled "From Forested to Urban Ecosystems: Refining Tree Health in American Elm (Ulmus americana) and American Beech (Fagus grandifolia)"

Both biotic and abiotic stressors can impact plant health, and these stressors have been heavily studied in model plants in controlled environments. Trees in field environments are subjected to pressure from multiple stressors that can collectively elicit a unique response, compared to the sum of responses by single stress elicitors. Understanding the ecological interactions between these stressors and the host can build a framework for improving plant health. Plant health is essential for the success of tree restoration projects. Urbanization, climate, soil chemistry, and pathogen incidence are contributing factors that can alter overall plant health. In the context of American elm (Ulmus americana), its susceptibility to devastating pathogens and its resilience to abiotic stresses are keys to its use in restoration in natural as well as anthropogenic systems. While the most notorious problem affecting American elm has been Dutch Elm Disease (DED), phytoplasmas pose an additional threat to elm tree populations. Currently, how these pathogens impact elm trees have not been well-characterized within the literature. Therefore, detection and identification assays must be developed to tackle questions about this pathosystem. Once pathogen detection and identification are optimized, questions on how these pathogens alter tree health can be answered. In his study, aside from providing pathogen detection tools, he proposed to characterize how urbanization, climate, soil chemistry, and pathogen incidence affect the urban elm system. As in humans, perturbations in health are reflected in trees by shifts in associated microbes, and consistent shift sin patterns in microbial identity or structure will reflect poor or declining health. As a complementary approach, he used near-infrared spectrometry to reveal signatures from stress; the exploitation of this technology can be used by forest professionals to identify plants under stress. His results better informed public and private institutions interested in elm restoration on how stress may impact trees; subsequently, best management practices could be altered based on the results from my study, to achieve optimal tree health. Another pathosystem of interest is Beech Leaf Disease (BLD) that presents a significant threat to hardwood ecosystems. Since 2012, the disease has spread to over 10 states and almost every county in Pennsylvania, decimating the beech stands present in the region. With a high tree mortality rate, improving our understanding of this disease is important for future mitigation efforts and to safeguard biodiversity. Pennsylvania's Allegheny National Forest (ANF) is home to forest-types with beech as a predominate species, especially in lower canopy growth. Additionally, most of these forests survived the impact of Beech Bark Disease (BBD) with new growth that may be resilient against BBD. With this work the objectives were to: 1.) survey the ANF to evaluate BLD distribution and severity across the region and 2.) characterize the microbial communities of different leaf tissues to evaluate changes in community composition on leaves with different symptoms. Microbes have the potential to inhibit or exacerbate disease severity and they can interact with their host, pathogens, and other microbes. Through characterizing these microbes, we can begin to hypothesize their function and inform the direction of future studies. As BLD is a rapidly spreading and ecologically devastating disease, understanding its disease dynamics is of high priority to a wide variety of stakeholders from local landowners to forest resource companies that need to improve tree health.

When asked about insight for prospective students, Miles responded,

"Making connections and networking are key to success in our interdisciplinary field. Take advantage of opportunities to meet, collaborate, and brainstorm with others."

Andrew Miles received the following awards during his graduate career at Penn State:

Delegate and Graduate Council Student Caucus Chair

2022-2023 Graduate Council Academic Standards Committee

Spring 2022: Leonard J. Francl Memorial Endowment in Plant Pathology

Travel Award to Plant Health 2022 [$500]

Fall 2021: PSU Science-to-Practice (S2P) Grant

Establishing Collaborative and Integrated Monitoring and Research on the Novel Beech Leaf Disease in Pennsylvania [$10,000]

Mary Smith

M.S., Plant Pathology

Mary Smith has accepted an offer to join the Molecular Microbiology and Immunology PhD program at the University of Texas San Antonio.

Smith's thesis is titled "Characterizing the S-type Bacteriocin in Psudomonas syringae."

She used bioinformatic methods to characterize s-type bacteriocin sequences in P. syringae.

Mary Smith received the following awards during her graduate career at Penn State:

• ARFI-NIFA predoctoral fellowship, $15,000 Northeast SARE Graduate Student Grant