Host plant genetic control of associated fungal and insect species in a Populus hybrid cross. Issue 11 (27th April 2020)

• Record Type: Journal Article
• Authors: Simon, Sandra J.; Tschaplinski, Timothy J.; M. LeBoldus, Jared; Keefover‐Ring, Ken; Azeem, Muhammad; Chen, Jin‐Gui; Macaya‐Sanz, David; MacDonald, William L.; Muchero, Wellington; DiFazio, Stephen P.
• Is Part Of: Ecology and evolution. Volume 10:Issue 11(2020)
• Page Start: 5119
• Page End: 5134
• Publication Date: 2020-04-27
• Subjects: community genetics -- comparative genomics -- plant–biotic interactions -- Populus -- tandem duplication; Ecology -- Periodicals; Evolution -- Periodicals; 577.05
• DOI: 10.1002/ece3.6266
• Languages: English
• ISSNs: 2045-7758

Abstract

Abstract: Plants employ a diverse set of defense mechanisms to mediate interactions with insects and fungi. These relationships can leave lasting impacts on host plant genome structure such as rapid expansion of gene families through tandem duplication. These genomic signatures provide important clues about the complexities of plant/biotic stress interactions and evolution. We used a pseudo‐backcross hybrid family to identify quantitative trait loci (QTL) controlling associations between Populus trees and several common Populus diseases and insects. Using whole‐genome sequences from each parent, we identified candidate genes that may mediate these interactions. Candidates were partially validated using mass spectrometry to identify corresponding QTL for defensive compounds. We detected significant QTL for two interacting fungal pathogens and three insects. The QTL intervals contained candidate genes potentially involved in physical and chemical mechanisms of host–plant resistance and susceptibility. In particular, we identified adjoining QTLs for a phenolic glycoside and Phyllocolpa sawfly abundance. There was also significant enrichment of recent tandem duplications in the genomic intervals of the native parent, but not the exotic parent. Tandem gene duplication may be an important mechanism for rapid response to biotic stressors, enabling trees with long juvenile periods to reach maturity despite many coevolving biotic stressors. Abstract : This work focuses on elucidating the host genetic drivers of community composition in a hybrid Populus family. We mapped quantitative trait loci for pathogenic fungi and leaf modifying insects in plantations and connected these to genomic intervals of the two host species. We found that tandemly duplicated genes were significantly enriched in the intervals and that these genes have functions that are consistent with rapid host co‐evolution with the interacting organisms.