Fecha de publicación: 11/02/2022 Fuente: Wipo Tobacco Agriculture The invention provides a codominant SSR marker closely linked with a tobacco black shank No.1 physiological race resistance gene qBS1. The codominant SSR marker can be used for detecting whether the tobacco black shank No.1 physiological race resistance gene qBS1 exists in tobacco genome DNA or not. Compared with the prior art, the resistance source type is quantitative character, the related black shank disease resistance is horizontal resistance, the resistance gene does not have linkage burdens, a finer QTL positioning result is achieved, and the marker is fast, stable, accurate and low in cost. The molecular marker can be applied to qBS1 gene molecular marker-assisted selection in disease-resistant breeding of No.1 physiological race of tobacco black shank.