The p19 protein of Grapevine Algerian latent virus is a determinant of systemic infection of Chenopodium quinoa

► We isolated Grapevine Algerian latent virus and Tomato bushy stunt virus. ► GALV causes systemic infection whereas TBSV causes only local lesions in Chenopodium quinoa. ► Host-specific activities of p19 are necessary for efficient systemic infection of C. quinoa by GALV. ► This is the first report to identify the viral factors for GALV systemic infection.