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We are glad that you are interested in the speakers for our 2020 WSU Plant Science Symposium. We are in the process of lining up 6 incredible professionals and 3 featured students to speak at the event.

Get excited, more information about our speakers will be announced soon!

Dr. David M Kramer

Professor at Michigan State University-DOE Plant Research Lab

Dr. Simon Gilroy

Professor at the University of Wisconsin-Madison

Dr. Jay Shockey

Research Geneticist, USDA-ARS Southern Regional Research Center

Dr. Uwe Sonnewald

Professor at University of Erlangen-Nuremberg

Dr. Sarah Bloch

Associate Research Director at Pivot Bio

Dr. Lyudmila Sidorenko

Principal Research Scientist at Corteva AgriSciences


Amanda McRae

Graduate student – University of California, Berkeley

Spray-induced gene silencing of powdery mildew genes reduces plant disease
A. McRae, J.Taneja, and M. Wildermuth

Spray-induced gene silencing (SIGS) is an emerging method to study gene function in plant pathogens and is being developed to protect crops from pests. It utilizes exogenously applied RNA designed to reduce gene expression in target organisms using endogenous RNA interference machinery. The widespread obligate biotrophic pathogen, powdery mildew, infects plants including wheat, barley, grape, and tomato which require fungicides to control. The goal of this study was to determine if powdery mildews are SIGS candidates and if so, develop a method to reduce powdery mildew growth using SIGS and screen for gene targets that contribute to fungal spore production. For this study we used the Arabidopsis thaliana-Golovinomyces orontii pathosystem. First, we demonstrated that G. orontii can uptake extracellular RNA using Fluorescein-labeled RNA. Next, we developed a SIGS method using the powdery mildew fungicide target CYP51 as a control gene to titrate dosage and timing of spray. Using SIGS, we screened 16 additional targets. Four out of ten metabolic genes tested contributed to fungal growth on Arabidopsis, with spore production reduced up to 50%. Two out of six effector genes targeted reduced fungal spore formation up to 33%. We have also shown these methods are translatable to grape powdery mildew, resulting in reduction of powdery mildew disease of grapevine. SIGS may be the future of controlling powdery mildew growth on crops because of its flexibility, reduced environmental and health risks, and rapid transition from the bench to the field.

Cellulose nanocrystal dispersions protect tree fruits from cold damage
B. Arnoldussen, J. Alhamid , C. Mo, X. Zhang, P. Wang, Q. Zhang, M. Whiting


Cold damage to reproductive buds or flowers is a perennial concern to tree fruit producers. Indeed, cold damage has caused more economic losses to crops in the US than any other weather hazard. The potential losses (yield reductions to complete crop failure) from cold damage are predicted to increase with variable weather patterns resulting from climate change. Cellulose nanocrystals (CNC) represents a new generation of renewable nano-biomaterials, with many unique physical and chemical properties, including their low thermal conductivity. Our team has developed a process for creating CNC dispersions that can be sprayed onto trees, forming a thin (ca. 25µm-40µm) and durable insulating film around the surface of the buds. Thermal image analyses revealed that apple (Malus domestica Borkh) and sweet cherry (Prunus avium L.) flower buds treated with 3% CNC dispersions lose 16.5% less thermal energy into the environment in cold conditions than untreated buds. Analyses of internal freezing events in apple with digital scanning calorimetry showed that buds coated in 3% CNC exhibited lethal freezing at a temperature 3.2°C and 5.5°C lower than the untreated control 1 and 3 days after application, respectively. Large-scale field trials using commercially available electrostatic sprayers showed that CNC-treated (2.5%) reproductive buds were hardier by ca. 5.8°C, a level of protection that lasted up to 7 days post application. The results of this work suggest that CNC dispersions can effectively protect reproductive buds from cold damage and may represent a novel means for fruit growers worldwide to reduce losses.

Brent Arnoldussen

Graduate Student – Washington State University, Prosser  IAREC