Assembly and annotation of Solanum dulcamara and Solanum nigrum plant genomes, two nightshades with different susceptibilities to Ralstonia solanacearum
Authors: Franco Ortega, S., James, S. R., Gilbert, L., Hogg, K., Stevens, H., Daff, J., Friman, V. P., Harper, A. L.
The study generated de‑novo genome assemblies for the resistant wild relative Solanum dulcamara and the susceptible Solanum nigrum using a hybrid Oxford Nanopore and Illumina sequencing strategy. Comparative genomic analyses identified auxin‑transport genes and novel pattern recognition receptor orthogroups unique to resistant species, as well as differential gene‑body methylation that may underlie resistance to Ralstonia solanacearum.
The study investigated unexpected leaf spot symptoms in Psa3‑resistant kiwifruit (Actinidia) germplasm, finding that Psa3 was detectable by qPCR and metabarcoding despite poor culturing. Metabarcoding revealed distinct bacterial community shifts in lesions versus healthy tissue, and whole‑genome sequencing identified diverse Pseudomonas spp. that, while not individually more pathogenic, could enhance Psa3 growth, suggesting pathogenic consortia on resistant hosts.