The necrotic ring spot virus ( Prunus necrotic ringspot virus ( PNRSV ) is a plant virus from the family Bromoviridae . It infects cherry trees (sweet Prunus avium and sour cherry ( Prunus cerasus )) as well as plum ( Prunus domestica ) and peach ( Prunus persica) ). In cherry trees infection with PNRSV leads to lower yields and if it together with the cherry leaf roll virus ( Cherry leaf roll virus occurs CLRV) to a rapid death of the tree. There are different strains of the virus (a, e, G).
Hosts and diffusion
Infection of sour cherries with PNRSV can occur during grafting, through seeds, pollen, root contact and the nematodes Longidorus macrosoma . In European sour cherries, the disease caused by the virus is known as "Stecklenberger disease". The disease manifests itself in the fact that the flower and leaf buds on individual shoots or parts of branches turn brown and dry up when they break open. The affected shoots and branches often die as a result. Older leaves have light green and brown rings, as well as irregular, necrotic spots that peel off, called the shotgun effect. In a recovery phase from the disease, leaf-like enations appear on the underside of the leaf.
Combating the disease is not possible, so infested trees should be removed.
