Kyle Lewald, doctoral candidate

His title: "Using Genomic Data to Understand and Prevent the Spread of Tuta absoluta." He will be introduced by Chiu, professor and vice chair, UC Davis Department of Entomology and Nematology. A pre-seminar coffee will take place from 3:30 to 4:10 in Briggs 158. 

T. absoluta, a species of moth in the family Gelechilidae, is a pest of tomato crops in its larval stage. It is also known as a tomato leafminer.

"Tuta absoluta is a serious agricultural pest of tomato plants," Lewald says in his abstract. "While initially discovered in Peru, it has rapidly invaded tomato fields around the world over the past century, causing widespread damage to the industry. The recent affordability of whole genome sequencing of insects opens the door to a wide number of applications to understand and control this pest."

"Using long read sequencing, we produced and annotated a highly contiguous T. absoluta genome assembly. Sequencing of individuals collected across many locations in Latin America allowed us to investigate population structure and diversity levels, as well as identify divergence times and possible migration events occurring between regions. Understanding these historical events can be key to predicting and preventing future invasion events. We also used comparative genomics between morphologically similar gelechiid species to develop efficient molecular diagnostics, allowing field researchers and stakeholders to identify Tuta absoluta rapidly to support quarantine and treatment efforts."

Lewald's research interests include studying population genetics and developing molecular diagnostics of pest insects. He received his bachelor's degree in molecular and cell biology from UC Berkeley in 2016. After studying circadian rhythms in sorghum with UC Berkeley professor Frank Harmon, he became interested in animal clock systems and joined the Chiu Lab in 2018.  

He has published his work in several journals: 

• Lewald, K. M., A. Abrieux, D. A. Wilson, Y. Lee, W. R. Conner et al., 2021 Population genomics of Drosophila suzukii reveal longitudinal population structure and signals of migrations in and out of the continental United States. G3 Genes|Genomes|Genetics jkab343.
• Lewald, K. M., and J. C. Chiu, 2020 Harnessing Transcriptomics to Study Insect Biology, in Transcriptomics in Entomological Research, CABI, Oxfordshire, UK.
• Tabuloc, C. A., K. M. Lewald, W. R. Conner, Y. Lee, E. K. Lee et al., 2019 Sequencing of Tuta absoluta genome to develop SNP genotyping assays for species identification. Journal of Pest Science. 
• Gao, J., J. Sasse, K. M. Lewald, K. Zhalnina, L. T. Cornmesser et al., 2018 Ecosystem Fabrication (EcoFAB) Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions. JoVE 57170.

The UC Davis Department of Entomology and Nematology's winter seminars are held on Wednesdays at 4:10 p.m. in 122 Briggs Hall. All are virtual. A pre-seminar coffee is held from 3:30 to 4:10 p.m. in 158 Briggs. Urban landscape entomologist Emily Meineke, assistant professor, coordinates the seminars. (See schedule.) She may be reached at ekmeineke@ucdavis.edu for technical issues.