Zhongguo Xiong, PhD, is an associate professor in the School of Plant Sciences, College of Agriculture and Life Sciences at the University of Arizona, and a faculty member in the Undergraduate Program of Microbiology. Dr. Xiong is a 2012 winner of the Bill Gates and Melinda Foundation Grand Challenges Explorations in Global Health, and has more than 20 years of research experience on RNA viruses of important crops and native plant species. Dr. Xiong research encompasses a wide range of subjects that include virus diversity, recombination, RNAi suppression, host resistance and resistance-breaking, replication and movement of RNA viruses, and how all these are related to the control and management of viral diseases. He was one of the first researchers to discover ribosomal frameshifting as a gene expression mechanism in plant RNA viruses and to demonstrate recombination between transgene mRNA and genomic RNA of an infecting virus. His recent research on Citrus tristeza virus has revealed its genome stability, unusual for an RNA virus, and the promiscuous recombination between viral strains as the major factor driving Citrus tristeza virus evolution. His recent collaboration with Dr. Martha Hawes has led to the discovery that extracellular DNA, secreted DNases, and proteins are important immunity and pathogenicity factors in the plant-microbe interactions in the rhizosphere. Dr. Xiong has strong ongoing international collaborations on emerging viral diseases of tomato, pepper, papaya, and banana. His recent research interests include genome editing to engineer immunity against viral infection and using the next generation sequencing to explore viral population genomics and genetic diversity and to discover new viruses and novel viral strains.