A complex resistance locus in Solanum americanum recognizes a conserved Phytophthora effector

Witek, K.; Lin, X.; Karki, H. S.; Jupe, F.; Witek, A. I.; Steuernagel, B.; Stam, R.; Van Oosterhout, C.; Fairhead, S.; Cocker, J. M.; Bhanvadia, S.; Barrett, W.; Song, T.; Vleeshouwers, V. G.; Tomlinson, L.; Wulff, B. B.; Jones, J. D.

doi:10.1101/2020.05.15.095497

bioRxiv · 10.1101/2020.05.15.095497

A complex resistance locus in Solanum americanum recognizes a conserved Phytophthora effector

Witek, K.·Lin, X.·Karki, H. S.·Jupe, F.·Witek, A. I.·Steuernagel, B.·Stam, R.·Van Oosterhout, C.·Fairhead, S.·Cocker, J. M.·Bhanvadia, S.·Barrett, W.·Song, T.·Vleeshouwers, V. G.·Tomlinson, L.·Wulff, B. B.·Jones, J. D.

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Abstract

Late blight caused by Phytophthora infestans greatly constrains potato production. Many Resistance (R) genes were cloned from wild Solanum species and/or introduced into potato cultivars by breeding. However, individual R genes have been overcome by P. infestans evolution; durable resistance remains elusive. We positionally cloned a new R gene, Rpi-amr1, from Solanum americanum, that encodes an NRC helper-dependent CC-NLR protein. Rpi-amr1 confers resistance in potato to all 19 P. infestans isolates tested. Using association genomics and long-read RenSeq, we defined eight additional Rpi-amr1 alleles from different S. americanum and related species. Despite only [~]90% identity between Rpi-amr1 proteins, all confer late blight resistance but differentially recognize Avramr1 orthologs and paralogs. We propose that Rpi-amr1 gene family diversity facilitates detection of diverse paralogs and alleles of the recognized effector, enabling broad-spectrum and durable resistance against P. infestans.

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Witek, K., Lin, X., Karki, H. S., Jupe, F., Witek, A. I., Steuernagel, B., Stam, R., Van Oosterhout, C., Fairhead, S., Cocker, J. M., Bhanvadia, S., Barrett, W., Song, T., Vleeshouwers, V. G., Tomlinson, L., Wulff, B. B., Jones, J. D.. 2020-05-16. A complex resistance locus in Solanum americanum recognizes a conserved Phytophthora effector. https://doi.org/10.1101/2020.05.15.095497

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