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Transgenic crops producing crystalline (Cry) proteins from the bacterium Bacillus thuringiensis (Bt) have been used extensively to control some major crop pests. However, many populations of the noctuid moth Helicoverpa zea, one of the most important crop pests in the United States, have evolved practical resistance to several Cry proteins including Cry1Ac. Although mutations in single genes that confer resistance to Cry proteins have been identified in lab-selected and gene-edited strains of H. zea and other lepidopteran pests, the genetic basis of field-evolved resistance to Cry proteins in H. zea has remained elusive. We used a genomic approach to analyze the genetic basis of field-evolved resistance to Cry1Ac in 937 H. zea derived from 17 sites in seven states of the southern United States. We found evidence for extensive gene flow among all populations studied. Field-evolved resistance was not associated with mutations in 20 single candidate genes previously implicated in resistance or susceptibility to Cry proteins in H. zea or other lepidopterans. Instead, resistance in field samples was associated with increased copy number of a cluster of nine trypsin genes. However, trypsin gene amplification occurred in a susceptible sample and not in all resistant samples, implying that this amplification does not always confer resistance and mutations in other genes also contribute to field-evolved resistance to Cry1Ac in H. zea . The mismatch between lab-generated and field-evolved resistance inH. zeais unlike other cases of Bt resistance and reflects challenges for managing this pest. 

From May 13-15, 2024, the University of Arizona Ecosystem Genomics Community, participated in the annual Convergence Institute. The Convergence Institute is a 3-day summit meeting that is equal parts science, training, inclusion, professional development, evaluation, and science communication. A student pre-session offers professional development on a variety of topics. Each year, participants hear from a rotating panel about the challenges of ecosystem genomics, then present and– depending on their cohort– receive feedback on their proposed or completed summer research experiences. Students who have completed their NRT requirements are invited to help lead sessions and introduce presentation themes. This report was written by students participating in the team skills and writing workshops presented during the pre-session by Dr. Anne Mook, Mook, a senior team scientist at the Institute for Research in the Social Sciences (IRISS) at Colorado State University. The report includes an executive summary, general components of the institute, objectives, 2024 institute overview, conclusions, a participant directory, organizers and panelist directory, presentation topics by theme and key takeaways, relevance of convergence research, future directions, defining and evaluating Ecosystem Genomics as an emerging field and Appendices.