Posted: October 20, 2020
Two graduate students in the Department of Plant Pathology and Environmental Microbiology received pre-doctoral fellowships from the U.S. Department of Agriculture, National Institute of Food and Agriculture (NIFA).
Department of Plant Pathology and Environmental Microbiology graduate students Justin Shih and Chauncy Hinshaw. IMAGE: PENN STATE
UNIVERSITY PARK, Pa. – Two graduate students in the Department of Plant Pathology and Environmental Microbiology received pre-doctoral fellowships from the U.S. Department of Agriculture, National Institute of Food and Agriculture (NIFA).
According to NIFA, these fellowships will develop new scientists and professionals to enter research, education and extension fields within the food and agricultural sciences. The aim of these grants is to cultivate future industry, government and academic leaders who can solve emerging agricultural challenges of the 21st century.
A summary of the students' projects can be found below.
Justin Shih
Enhancing Crop Improvement by Improving Rates of Homology-Dependent-Repair for CRISPR-Cas9 Genome Editing
Shih's research interests include how to breed more resilient and productive food crops such as rice.
This will be critical to global society as it moves towards sustainable practices while weathering the effects of climate change and population growth. With this urgency, traditional breeding alone is too slow, often taking five or more years to develop a genetically improved crop. Fortunately, genome editing technology can expedite the process down to one year by directly tweaking specific genes in a plant genome. Currently, these tweaks only comprise of nullifying a gene and changing certain DNA letters if they are in the right position. While these two applications can be used to improve a vast amount of plant traits, geneticists and breeders have been striving for the additional abilities to precisely replace, delete and insert pieces of DNA – including sizes large enough for many genes at once. These processes are possible with certain genome editing strategies, but they remain too inefficient for practical purposes. Thus, with the USDA NIFA AFRI predoctoral fellowship, Justin is exploring methods to enhance these processes. Using tobacco plants as a model system, he will evaluate chemical, genetic, or nanomaterial means to improve genome editing in their leaves. By broadening the power of genome editing, breeders can quickly adapt to changing pressures on farmers' crops such as disease outbreaks, intense weather, and demand for yield or improved qualities.
Chauncy Hinshaw
Host Tolerance: Understanding how Plant Hosts Mitigate Virus Infections and Consequences for Plant-Insect Interactions
Hinshaw's research focuses on understanding host tolerance to plant viruses and potential consequences of plant viruses for pollinator health to determine its viability as a disease management strategy.
Plant viruses cause significant crop losses every year. Breeding efforts typically focus on disease resistance in crops, but its success is often short-lived because viruses can quickly evolve to overcome this resistance. In contrast, host tolerance allows for viruses to infect a plant but with little to no disease and may provide more durable disease management. Additionally, bees provide vital pollination services to crops and many bee populations are in decline due to various factors including habitat loss and poor nutrition. However, it is largely unknown how plant diseases may affect the ability of plants to attract pollinators or change the nutritional quality of pollen and nectar for visiting insects. Proper plant disease management and methods to support bee populations and pollination services are vital for sustainable agriculture. Therefore, the goals of this project are to understand genetic mechanisms of virus tolerance and potential consequences of tolerance for plant and pollinator health, to determine its viability as a disease management strategy. Squash plants (Cucurbita spp.) will be used with low, moderate and high tolerance to Zucchini yellow mosaic virus to perform comparative gene expression experiments that will help identify genetic mechanisms conferring virus tolerance. Additionally, field experiments will be performed to understand how tolerance affects plant fitness by measuring traits such as pollination success, flower production and plant yields. Lastly, nutritional content of flowers from virus-infected plants will be measured to assess consequences of virus tolerance for pollinator health. This research will provide insight into host tolerance as a novel disease management strategy to decrease crop losses caused by plant viruses. This project will also identify plant traits that are important for pollinator visitation and pollinator health, increasing the scientific understanding of how diseases affect plant-pollinator interactions and the ability to breed crops that are more attractive and more nutritious to pollinators. These concepts could then be applied to a wide range of crops for increased sustainability of agriculture.
