Summary: | Recessive resistance against potyviruses, such as <i>Potato virus Y</i> (PVY), relies on mutations in the eukaryotic translation initiation factor 4E (eIF4E) or one of its isoforms. The <i>eIF4E1-S</i> mutants of burley tobacco (<i>Nicotiana tabacum</i> L.) exhibit recessive resistance against PVY strains. Here, we developed a TILLING population of flue-cured tobacco (<i>N. tabacum</i> cv. Yunyan87) using ethyl methanesulfonate (EMS) to identify <i>eIF4E1-S</i> mutants. M3 plants homozygous for a nonsense mutation in exon 1 of the <i>eIF4E1-S</i> gene demonstrated resistance against PVY<sup>MN</sup>. These M3 plants were backcrossed to ‘Yunyan87’, and BC<sub>4</sub>F<sub>3</sub> plants were screened using derived cleaved amplified polymorphic sequence (dCAPS) markers. BC<sub>4</sub>F<sub>3</sub> plants showing agronomic traits comparable to the recurrent parent ‘Yunyan87’ and resistance against PVY<sup>O</sup>, PVY<sup>N</sup>, and PVY<sup>NTN</sup> strains were identified. These genotypes would provide useful germplasm for future tobacco improvement and would aid in basic research on PVY resistance in flue-cured tobacco.
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