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Jean Ristaino


Entomology and Plant Pathology Department, NC State

Gardner Hall 2419


Jean Beagle Ristaino earned her B.S. degree in Biological Sciences and M.S. degree in Plant Pathology from the University of Maryland, and her Ph.D. in Plant Pathology from the University of California-Davis.  Upon graduation she joined the Department of Plant Pathology at North Carolina State University, advancing to full professor in 1998. She was named a William Neal Reynolds Distinguished Professor in February of 2012. Much of Dr. Ristaino’s work has been on the Oomycete pathogens in the genus Phytophthora. She works on the population genetics of historical potato famine epidemics and studies the population structure of present day late blight outbreaks.  Ristaino’s lab was the first to develop pioneering research techniques to recover DNA from 150-year-old historic herbarium specimens and determine that the strain that caused the potato famine was a Ia mt haplotype.  Her work documented an Andean origin for P. infestans and tracked it migration to the US and Ireland. She has also described new species of Phytophthora including P. andina the closest relative of P. infestans found in South America and she has developed taxonomic keys for identification.  Her research has been published in Nature, Science, and Proceedings of the National Academy of Sciences. Her research uses molecular tools for addressing basic ecological questions concerning the spread of microorganisms in nature. She conducts Phytophthora diagnostics workshops in Latin America. Dr. Ristaino’s late blight research has been featured on CNN, Discovery Channel, radio (NPR, BBC, Voice of America) and in newspaper and magazine articles. Dr. Ristaino’s research has not only impacted the understanding and direction of plant pathology, but has also influenced how the general public and policy makers view science and scientists.  She serves as a Senior Science advisor and Jefferson Science Fellow at USAID Washington in the Bureau of Food Security.

Area(s) of Expertise

Oomycete diseases, Population Genetics, Epidemiology, Food Security


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Date: 09/01/18 - 8/31/23
Amount: $2,997,865.00
Funding Agencies: National Science Foundation (NSF)

Challenges at the FEW nexus are not simply technological, but convergent in the sense of spanning technical, ecological, social, political, and ethical issues. The field of biotechnology is evolving rapidly - and with it, the potential for creating a diverse array of powerful future products that could intentionally and unintentionally impact FEW systems. Depending on what products are developed and how those products are deployed, biotechnology could have a positive or negative impact on all 3 of these systems. Wise decisions will require leaders who can integrate knowledge from engineering, design, natural sciences, and social sciences. We will train STEM graduate students to respond to these challenges by conducting convergent research aimed at development, and assessment of biotechnologies to improve services provided by FEW systems. We will train our students to engage with non-scientists to elevate societal discourse about biotechnology. We will recruit 3 cohorts with emphasis on students who have shown a passion for crossing between natural and social sciences. We will work with the NCSU Initiative for Maximizing Student Diversity in recruiting students from underrepresented minority groups. Cohorts will have 6 students who will take a minor in Genetic Engineering and Society (GES). They will receive PhDs in established graduate programs such as Plant Biol, Chem & Biomol Engr, Econ, Public Adm, Entomol, Plant Path, Communication, Rhetoric & Digital Media, Forestry & Environ Res, Crop & Soil Sci, and Genetics. For students in natural science PhD programs, at least 1 thesis committee member will be from a social sciences program and vice versa for students in social sciences. For all students, at least 1 thesis chapter will demonstrate scholarship across natural and social sciences. The disciplinary breadth of our proposed NRT is very broad, so we will focus student projects narrowly on a specific biotechnology product that impact FEW systems. When they first arrive at NCSU, cohorts will participate in a training program off campus where they will be exposed to the issues they will address. Students will carry out a group project in the focus area of the cohort to continue team development. To fulfill the GES minor, students will take 3 specially designed courses: Plant Genetics & Physiology, Science Communication & Engagement, Policy & Systems Modeling. There are no NRT-eligible institutions partnering on this project outside of an evaluation role.

Date: 02/17/20 - 6/30/23
Amount: $437,304.00
Funding Agencies: Game-Changing Research Incentive Program for Plant Sciences (GRIP4PSI)

Emerging plant disease and pest outbreaks reduce food security, national security, human health, and the environment, with serious economic implications for North Carolina growers. These outbreaks may accelerate in coming decades due to shifts in the geographic distributions of pests, pathogens and vectors in response to climate change and commerce. Data-driven agbioscience tools can help growers solve pest and disease problems in the field more quickly but there is an urgent need to harness game-changing technologies. Computing devices are now embedded in our personal lives with sensors, wireless technology, and connectivity in the “Internet of Things” (IoT) but these technologies have yet to be scaled to agriculture. Our interdisciplinary team will build transformative sensor technology to identify plant pathogens, link local pathogen data and weather data, bioinformatics tools (pathogen genotypes), and use data driven analytics to map outbreaks, estimate pest and pathogen risk and economic damage, in order to coordinate response to emerging diseases, and contain threats. Sensor-supported early and accurate detection of pathogens before an outbreak becomes wide-spread in growing crops will significantly reduce pesticide use and increase crop yields.

Date: 07/01/21 - 6/30/22
Amount: $301,048.00
Funding Agencies: US Dept. of Agriculture - Animal and Plant Health Inspection Service (USDA APHIS)

Improvements in field-based pathogen diagnostics are needed since plant disease outbreaks exact a heavy toll on agriculture. Use of new innovations in science and technology including field-compatible molecular assays such as loop-mediated isothermal amplification (LAMP) and volatile-based sensors may speed identification of plant pathogens in fields and allow growers to respond more rapidly with appropriate fungicide treatments and for regulatory agencies to mitigate new outbreaks. In this project, we will develop in-field volatile organic compound (VOC) sensors and microneedle patch-supported LAMP sensors that can differentiate several important Phytophthora species of regulatory concern including P. infestans, P. ramorum and P. kernoviae. Phytophthora infestans infects potato and tomato, while P. ramorum and P. kernoviae cause disease on nursery plants such as rhododendron, lilac and kalmia and important forestry tree species including oak and beech among others. P. kernoviae has not yet been found in the US. We will develop species- specific LAMP and VOC sensors and deploy these sensors for use with inexpensive cartridges that are read from a smartphone. The sequence data collected from the LAMP sensor platforms and previously published sequence databases will be uploaded to create an open buildable phylogeny of emerging Phytophthora’s. Pathogen occurrence data collected will be linked with a near real-time web-based GIS platform and a weather-based susceptible infected (SI) host spatial-temporal POP’s (Pest and Pathogen Spread) model to develop predictive maps of pathogen risk. The system will improve the response time of USDA APHIS PPQ and National Plant Diagnostic Network (NPDN personnel to respond to emerging threat pathogens and improve economic return of growers as they use the digital diagnostic tools to prevent the spread of important Phytophthora diseases.

Date: 03/15/19 - 3/14/22
Amount: $200,000.00
Funding Agencies: US Dept. of Agriculture - National Institute of Food and Agriculture (USDA NIFA)

Crop production and disease protection present global concerns in every region of the world. Current diagnostic methods of plant diseases are heavily focused on genetic molecular assays (e.g., PCR) or immunological biosensors (e.g., antibody-based lateral flow assay or ELISA), most of which are time-consuming and invasive for sample preparation, subject to instability of reagents, and lack of an integrated framework for on-site data analysis and sharing. On the other side, there is an increasing need for rapid, noninvasive, yet highly cost-effective and connected sensors which can identify multiple infectious species simultaneously in the crop field and monitor disease outbreaks spatiotemporally. Here, we propose to develop a transformative smartphone-based optical sensing platform that enables the early diagnosis of plant diseases (e.g., potato late blight) caused by associated fungal or bacterial infections, based on the identification of characteristic volatile organic compounds (VOC) released from different plant disease models using a disposable chemo-responsive nanoplasmonic sensor array combined with multimodal smartphone readout (brightfield + fluorescence). This project is expected to provide an economically vital, field-deployable, and noninvasive solution for early diagnosis of various important plant diseases or monitoring of abiotic stresses with a high degree of detection sensitivity and specificity.

Date: 01/01/20 - 2/28/22
Amount: $339,045.00
Funding Agencies: BASF Corporation

The overarching goal of this project is to systematically study and optimize two microneedle-based platforms for rapid DNA extraction and genotyping from plant leaves and seeds, respectively. DNA genotyping is an indispensable tool to identify specific traits and select progeny in plant breeding. However, the current seed genotyping method is a complicated multistep process, involving seed chipping, DNA extraction, and assaying. On the other side, leaf genotyping is relatively simpler, but it depends on manual punctuation of leaf tissues and actual breeding of new crop species before analysis, which increases both time and test cost significantly. To address these immediate needs, our team will investigate a novel plant DNA extraction and genotyping system that is robust, simple, and scalable for single-nucleotide polymorphism (SNP) analysis for both plant leaves and seeds. Two DNA extraction platforms, namely the polymeric microneedle array (PMA) and metallic microneedle (MM), will be developed and optimized for leaf and seed DNA isolation, respectively. The extraction system will be integrated with a multiplexed genotyping assay such as padlock-based rolling circle amplification (RCA) for rapid detection of specific trait loci markers. The potential for on-needle detection of SNPs and automation of the entire process will also be explored.

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