Preprint / Common molecular determinants underlie potyvirus host species jumps and resistance breakdown

This article is a preprint and has not been certified by peer review

Moury, B., Szadkowski, M., Wipf-Scheibel, C., Girardot, G., Papaix, J., Roques, L., Agrofoglio, Y., Valli, A.A., Berthier, K., Desbiez, C., (2026) Common molecular determinants underlie potyvirus host species jumps and resistance breakdown. https://doi.org/10.64898/2026.07.09.737469

Abstract: Given their rapid evolutionary dynamics, viruses offer a powerful system to investigate the mechanisms underlying host jumps. Here, we experimentally evolved endive necrotic mosaic virus (ENMV) in five plant hosts within the family Asteraceae: two putative ancestral hosts (Lactuca sativa and Tragopogon pratensis), and three alternative crop or weed species (Cichorium endivia, Zinnia elegans and Calendula arvensis). The resulting evolved viral populations, together with the ancestral strain, were then evaluated in a reciprocal cross-inoculation experiment across all five host species.

ENMV exhibited clear adaptive responses in two hosts, Z. elegans and C. arvensis, with increased infection success and higher systemic viral accumulation compared to the ancestral virus. In contrast, no evidence of adaptation was detected in L. sativa, T. pratensis and C. endivia. Strikingly, strong cross-adaptation emerged between Z. elegans and C. arvensis: viral populations evolved in either host consistently outperformed those evolved in other hosts, as well as the ancestral strain, when infecting the reciprocal host.