Physical and chemical characterization of wild tomato Solanum habrochaites accessions for resistance to the sweetpotato whitefly

Authors: RUTZ, THIAGO - Auburn University; PIZZO, JESSICA - Auburn University; JACOBSON, ALANA - Auburn University; MAJUNDAR, AYANAVA - Auburn University; SIKORA, EDWARD - Auburn University; COOLONG, TIMOTHY - University Of Georgia; Simmons, Alvin; KARTOWIKROMO, KIMBERLY - Auburn University; HAMID, AHMED - Auburn University; OJEDA, ANN - Auburn University; RODRIGUES, CAMILA - Auburn University; DA SILVA, ANDRE - Auburn University

Submitted to: Plant Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2024
Publication Date: 12/1/2024
Citation: Rutz, T., Pizzo, J.S., Jacobson, A.L., Majundar, A., Sikora, E.J., Coolong, T., Simmons, A.M., Kartowikromo, K.Y., Hamid, A.M., Ojeda, A.S., Rodrigues, C., Da Silva, A.L. 2024. Characterization of physical and chemical resistance of wild tomato accessions of Solanum habrochaites to whiteflies. Plant Science. 338: Article (2024) 113687. https://doi.org/10.1016/j.scienta.2024.113687.
DOI: https://doi.org/10.1016/j.scienta.2024.113687

Interpretive Summary: The sweetpotato whitefly is a global insect pest that damages tomato crops. A study was conducted to assess whitefly resistance by eight selected wild tomato accessions as compared with four selected commercial tomato cultivars. The wild tomato accessions had higher numbers of glandular hairs and distinct chemical profiles; moreover, whiteflies on these wild plant types laid fewer eggs and there was less immature development. The resistant wild plants had higher levels of a group of chemicals including a-zingiberene, ß-caryophyllene, and a-humulene. Results from this study will be useful to help scientists to breed tomatoes that are more resistant to whiteflies.

Technical Abstract: The whitefly Bemisia tabaci is a significant worldwide insect pest affecting tomato production. Whiteflies can cause direct damage during feeding, but also can transmit multiple plant viruses to tomato. Continuing research to improve integrated pest management (IPM) of whiteflies is required to maintain tomato production that is profitable for growers. Therefore, the objective of this study was to evaluate the resistance of eight wild tomato accessions of Solanum habrochaites and four commercial tomato cultivars of Solanum lycopersicum to whitefly infestation. Field experiments were conducted at the Wiregrass Research and Extension Center at Auburn University where whitefly populations have been reported in both row crops and vegetables. Accessions and cultivars were evaluated against whitefly populations with a focus on several plant physical and chemical characteristics. Results indicated significant variations in whitefly population dynamics among the wild tomato accessions and commercial tomato cultivars. Wild tomato accessions of S. habrochaites had higher numbers of glandular trichomes and distinct terpene profiles, particularly sesquiterpenes which are known for their pest-repellent properties. Multivariate analysis identified three clusters based on terpene profiles and trichome types correlating with whitefly resistance. Particularly, accessions of S. habrochaites PI127826, PI134418, and G29258 had prominent results. They significantly reduced whitefly oviposition and nymph development compared to cultivars of S. lycopersicum. The GC-MS analysis of leaf extracts revealed that accessions of S. habrochaites had higher levels of sesquiterpenes, including a-zingiberene, ß-caryophyllene, and a-humulene, with PI127826 uniquely producing Ar-curcumene and 9-hydroxy-zingiberene. Results highlight the potential of wild tomato accessions of S. habrochaites in breeding programs aimed to enhance whitefly resistance in tomatoes which can support sustainable IPM program.